DE10058290A1 - Process for stabilizing polyolefins - Google Patents

Abstract

A method for the production of polyolefins which are subjected to the effect of water and stabilized against visible and ultraviolet light, wherein light stabilizers are added to the polyolefin. The inventive method is characterized in that the light stabilizers are selected from the following compounds a) d): a) cyanoacrylic acid esters of formula 1, b) 4,4 diarylbutadienes of formula II, c) benzophenones of formula III, d) cinnamic acid esters of formula IV, the variables having the meaning cited in the description.

Description

The invention relates to a process for the production of poly olefins exposed to water and the are stabilized against visible and ultraviolet light to which one adds light stabilizers to the polyolefin.

The invention further relates to methods for reducing the Yellowing of stabili against visible and ultraviolet light based polyolefins exposed to water are.

In addition, the invention relates to yellowing when exposed to water practice-resistant, stabilized against visible and ultraviolet light lized polyolefins, as well as moldings, foils and foams these polyolefins.

Finally, the invention relates to the use of light stabilizers in polyolefins that are exposed to water are exposed.

Polyolefins, especially the homo- and copolymers of ethylene and propylene, are usually used against visible and ul traviolettes (UV) light stabilizes to prevent damage to the poly counteracting by photooxidation. In 1988 approx. 75% of the light stabilizers used in plastics (light protection medium) used in polyolefins (R. Gächter, H. Müller, Plastics Additives Handbook, 4th edition, Hanser Verlag Munich 1993, reprint 1996, p. 130).

Polyolefins that contain light stabilizers and exposure Exposed to water usually show one over the course yellowing increasing in time: the initially opaque, white or light intrinsic color changes under the influence of water from yellowish to brownish. This yellowing is from aesthetics undesirable reasons. The effects of water are poly exposed to olefins in numerous applications, e.g. B. in pipes for drinking water and waste water, fittings for drinking water and waste water tubes, for packaging and foils, in particular packaging for Cosmetics (e.g. shampoo, creams, other water-containing cosmetics products) and packaging and foils for food (e.g. Fruit, vegetables, meat and other water-containing foods), for Drinking water bottles, in the entire outdoor area such. B. garden furniture furniture, windows and fittings, luminaire housings, vehicle exterior parts, etc. The disadvantageous yellowing makes it difficult or frustrates them  Use of polyolefins in applications where art is exposed to water.

The task was to remedy the disadvantages described. In particular, the task was to provide a method with which light stabilized polyolefins are available, which yellow much less under the influence of water than the light stabilized polyolefins of the prior art Technology.

There was also the task of stabilizing poly against light To provide olefins that are significantly lower in water Yellowing than the known stabilized polyolefins.

Accordingly, the process defined at the outset for the production of polyolefins found. It is characterized in that the Light stabilizers are selected from the following Compounds a) to d)

a) Cyanoacrylic acid esters of the formula I.

With
R ^I and R ^{II are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkenyl, C ₁ -C ₁₂ alkoxy, aryl, hetero aryl, optionally substituted,
X ethyl, 2-ethylhexyl, pentaerythrityl, propane-1,2,3-triyl, polyalkylene glycol residue,
n integer from 0 to 3,
m integer from 1 to 4,

b) 4,4-diarylbutadienes of the formula II

in which the diene system in the Z, Z; Z, E; E, Z or E, E configuration or a mixture thereof and in which the variables have the following meaning independently of one another:
R ¹ and R ^{2 are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₁ -C ₁₂ alkoxy, C ₁ - C ₂₀ alkoxycarbonyl, C ₁ -C ₁₂ alkylamino, C ₁ -C ₁₂ dialkylamino, aryl, heteroaryl, optionally substituted,
water-solubilizing substituents selected from the group consisting of carboxylate, sulfonate or ammonium residues;
R ³ hydrogen, COOR ⁵ , COR ⁵ , CONR ⁵ R ⁶ , CN, O = S (-R ⁵ ) = O, O = S (-OR ⁵ ) = O, R ⁷ OP (-OR ⁸ ) = O, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₇ -C ₁₀ bicycloalkenyl, aryl, Heteroaryl, optionally substituted;
R ⁴ COOR ⁶ , COR ⁶ , CONR ⁵ R ⁶ , CN, O = S (-R ⁶ ) = O, O = S (-OR ⁶ ) = O, R ⁷ OP (-OR ⁸ ) = OC ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₇ -C ₁₀ bicycloalkenyl, aryl, heteroaryl, if appropriate substituted;
R ⁵ to R ^{8 are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₇ -C ₁₀ bicycloalkenyl, aryl, heteroaryl, optionally substituted;
n 1 to 3,
where the variables R ³ to R ⁸ together, in each case together with the carbon atoms to which they are bonded, can together form a 5- or 6-ring, which can optionally be fused further,

c) Benzophenones of the formula III

With
Y is hydrogen, COOR ^I or OH, Z OR ^I or

A is hydrogen or SO ₃ H,
wherein R ^I and R ^{II have} the meaning given in a), and

d) cinnamic acid esters of the formula IV

where R ^I , R ^II and n have the meaning given in a).

In addition, the reduction method defined at the outset of yellowing found. It is characterized in that the light stabilizers used are selected from the Compounds as defined above under a) to d).

The invention further relates to the poly defined at the outset olefins, containing at least one of the light stabilizers Compounds a) to d) as defined above, and moldings, Films and foams made from this polyolefin.

Finally, the invention relates to the aforementioned Use of light stabilizers, these being selected from the compounds a) to d) as defined above.

Water includes all types of water, especially drinking water, waste water of households and businesses, distilled, ent ionized and demineralized water, rainwater, groundwater,  Surface water (rivers, lakes), sea water, spring water as well as mineral and medicinal water.

All polymers of olefins are suitable as polyolefins, ins special polymers of ethylene, propylene, but-1-ene, isobutylene and 4-methylpentene.

Polymers are said to be both homopolymers and copolymers from one of the monomers mentioned as the main monomer and others Monomers are understood as comonomers.

Preferred polyolefins are the homopolymers and copolymers of Ethylene and the homopolymers and copolymers of propylene.

Ethylene polymers

Suitable polyethylene (PE) homopolymers are e.g. B .:

• - PE-LD (LD = low density), available according to the high pressure process (ICI) at 1000 to 3000 bar and 150 to 300 ° C with oxygen or peroxides as catalysts in autoclaves or tubular reactors. Heavily branched with branches of different lengths, crystallinity 40 to 50%, density 0.915 to 0.935 g / cm ³ , average molecular weight up to 600,000 g / mol.
• - PE-LLD (LLD = linear low density), available with metal comm plex catalysts in the low pressure process from the gas phase, from a solution (e.g. petrol), in a suspension or with a modified high pressure process. Weakly branched with in unbranched side chains, molecular weights higher than in LDPE.
• - PE-HD (HD = high density), available according to the medium pressure (Phillips) and low pressure (Ziegler) process. According to Phillips at 30 to 40 bar, 85 to 180 ° C, chromium oxide as a catalyst, molar masses about 50,000 g / mol. According to Ziegler at 1 to 50 bar, 20 to 150 ° C, titanium halides, titanium esters or aluminum alkyls as catalysts, molar mass about 200,000 to 400,000 g / mol. Carried out in suspension, solution, gas phase or mass. Very weakly branched, crystallinity 60 to 80%, density 0.942 to 0.965 g / cm ³ .
• - PE-HD-HMw (HMW = high molecular weight), available after Ziegler, Phillips or gas phase method. High density and high molecular weight.  
• - PE-HD-UHMW (UHMW = ultra high molecular weight) available with modified Ziegler catalyst, molecular weight 3,000,000 to 6,000,000 g / mol.

Polyethylene, which is in a gas phase vortex, is particularly suitable bed process using (usually supported) Catalysts is made, e.g. B. Lupolen® (Elenac).

Polyethylene is particularly preferred, which using Metallocene catalysts is produced. Such polyethylene is z. B. commercially available as Luflexen® (Elenac). The metal Oxene catalyst system is described in more detail below.

The following compounds of the general formula are suitable as metallocene complexes:

in which the substituents have the following meaning:
M titanium, zirconium, hafnium, vanadium, niobium or tantalum,
X fluorine, chlorine, bromine, iodine, hydrogen or C ₁ - to C ₁₀ -alkyl,
R ⁸ to R ^{12 are} hydrogen, C ₁ to C ₁₀ alkyl, 5- to 7-membered cycloalkyl, which in turn can carry a C ₁ to C ₁₀ alkyl as a substituent, C ₆ to C ₁₅ aryl or aryl alkyl, where optionally two adjacent radicals may together represent cyclic groups having 4 to 15 carbon atoms or Si (R ¹³ ) ₃ with
R ^{13 is} C ₁ to C ₁₀ alkyl, C ₃ to C ₁₀ cycloalkyl or C ₆ to C ₁₅ aryl,
Z for x or

stands,
being the leftovers
R ¹⁴ to R ^{18 are} hydrogen, C ₁ to C ₁₀ alkyl, 5- to 7-membered cycloalkyl, which in turn can carry a C ₁ to C ₁₀ alkyl as a substituent, C ₆ to C ₁₅ aryl or arylal mean kyl and, where appropriate, two adjacent radicals may together stand for cyclic groups having 4 to 15 carbon atoms, or Si (R ¹⁹ ) ₃ with
R ^{19 is} C ₁ to C ₁₀ alkyl, C ₆ to C ₁₅ aryl or C ₃ to C ₁₀ cycloalkyl,
or wherein the radicals R ¹¹ and Z together form a group -R ²⁰ -A, in which

where R ²¹ , R ²² and R ²³
are identical or different and are a hydrogen atom, a halogen atom, a C ₁ -C ₁₀ alkyl group, a C ₁ -C ₁₀ fluoroalkyl group, a C ₆ -C ₁₀ fluoroaryl group, a C ₆ -C ₁₀ aryl group, a C ₁ -C ₁₀ alkoxy group, a C ₂ -C ₁₀ alkenyl group, a C ₇ -C ₄₀ arylalkyl group, a C ₈ -C ₄₀ arylalkenyl group or a C ₇ -C ₄₀ alkylaryl group or where two adjacent radicals each with the atoms connecting them form a ring, and
M ^{3 is} silicon, germanium or tin,
A -O-, -S-, NR ²⁴ or PR ²⁴ mean with
R ²⁴ C ₁ to C ₁₀ alkyl, C ₆ to C ₁₅ aryl, C ₃ to C ₁₀ cycloalkyl, alkylaryl or Si (R ²⁵ ) ₃ ,
R ^{25 is} hydrogen, C ₁ to C ₁₀ alkyl, C ₆ to C ₁₅ aryl, which in turn can be substituted by C ₁ to C ₄ alkyl groups or C ₃ to C ₁₀ cycloalkyl
or wherein the radicals R ¹¹ and R ¹⁷ together form a group -R ²⁰ -.

Particularly suitable metallocene complexes are, for example DE-A 198 06 435, page 3, line 68 to page 5, line 67 described. It is expressly referred to the text passage directed.

The synthesis of such complex compounds can in itself known methods take place, the implementation of the corresponding substituted, cyclic hydrocarbon anions with halogeni that of titanium, zirconium, hafnium, vanadium, niobium or tantalum, is preferred.

Examples of corresponding manufacturing processes include. a. in the Journal of Organometallic Chemistry, 369 (1989), 359-370 described.

Mixtures of different metallocene complexes can also be used be set.

As a rule, the metallocene complexes are activated by an activator connection activated. Suitable activators are in particular Compounds that form metallocenium ions.

Suitable metallocenium ion-forming compounds are in particular their complex compounds, selected from the group of strong, neutral Lewis acids, the ionic compounds with Lewis acids Cations and the ionic compounds with Bronsted acids as Cation.

Compounds of the general formula are strong, neutral Lewis acids

M ⁴ X ¹ X ² X ³

preferred in the
M ^{4 is} an element of III. Main group of the periodic table means, in particular B, A1 or Ga,
X ¹ , X ² and X ³
for hydrogen, C ₁ - to C ₁₀ alkyl, C ₆ - to C ₁₅ aryl, alkyl aryl, arylalkyl, haloalkyl or haloaryl, each with 1 to 10 C atoms in the alkyl radical and 6 to 20 C atoms in the aryl radical or fluorine , Chlorine, bromine or iodine, in particular halogen aryls, preferably pentafluorophenyl.

As ionic compounds with Lewis acid cations are compounds of the general formula

[(Y ^{a +} ) Q ₁ Q ₂ . , .Qz] d ⁺

suitable in which
Y is an element of I. to VI. Main group or the I. to VIII. Subgroup of the periodic table means
Q ¹ to Q ² for single negatively charged radicals such as C ₁ to C ₂₈ alkyl, C ₆ to C ₁₅ aryl, alkylaryl, arylalkyl, haloalkyl, haloaryl, each having 6 to 20 C atoms in the aryl and 1 to 28 C atoms in the alkyl radical, C ₁ - to C ₁₀ -cycloalkyl, which can optionally be substituted by C ₁ - to C ₁₀ -alkyl groups, halogen, C ₁ - to C ₂₈ -alkoxy, C ₆ - to C ₁₅ -aryloxy , Silyl or mercaptyl groups
a stands for integers from 1 to 6
z for integers from 0 to 5
d corresponds to the difference az, but d is greater than or equal to 1.

Carbonium cations, oxonium cations and Sulfonium cations and cationic transition metal complexes. in the special are the triphenylmethyl cation, the silver cation and to name the 1,1'-dimethylferrocenyl cation. Prefer to own they do not coordinate counterions, especially boron compounds gene, as they are also mentioned in WO-A 91/09882, preferred Tetrakis (pentafluorophenyl) borate.  

Ionic compounds with Bronsted acids as cations and before counterions, which are likewise not coordinating, are in the WO-A 91/09882 called, preferred cation is the N, N-dimethyl anilinium.

All commercially available ethylene copoly are ethylene copolymers suitable, for example Luflexen® types (Elenac), Nordel® and Engage® (Dow, DuPont). All α-olefins are included as comonomers 3 to 10 carbon atoms suitable, in particular propylene, but-1-ene, Hex-1-ene and oct-1-ene, as well as alkyl acrylates and methacrylates with 1 to 20 carbon atoms in the alkyl radical, especially butyl acrylate. Other suitable comonomers are dienes such as. B. Butadiene, Iso pren and octadiene and dicyclopentadiene.

They are usually statistical copolymers or Block or impact copolymers.

Block or impact copolymers of ethylene and comonomers are Polymers in which a homopolymer of Comonomers or a random copolymer of the comonomer with up to 15 wt .-%, preferably up to 6 wt .-% ethylene and then in the second stage with a comonomer-ethylene copolymer Polymerized ethylene contents of 15 to 80 wt .-%. In the As a rule, as much of the comonomer-ethylene copolymer is added siert that the copolymer produced in the second stage in the end pro has a share of 3 to 60% by weight.

The polymerization to produce the ethylene comonomer copoly mere can be done using a Ziegler-Natta catalyst system Such catalyst systems are used in particular used in addition to a titanium-containing solid component Cocatalysts in the form of organic aluminum compounds and Have electron donor compounds.

But catalyst systems based on metal can also be used ocenverbindungen or on the basis of polymerization active Metal complexes are used.

Propylene polymers

The term polypropylene is to be understood below to mean both homopolymers and copolymers of propylene. Copolymers of propylene contain minor amounts of monomers copolymerizable with propylene, for example C ₂ -C ₈ -alk-1-enes such as ethylene, but-1-ene, pent-1-ene or hex-1-ene. Two or more different comonomers can also be used.

Suitable polypropylenes include a. Homopolymers of propylene or Copolymers of propylene polymerized with up to 50% by weight other alk-1-enes with up to 8 carbon atoms. The copolymers of the Pro pylens are statistical copolymers or block or Im pactcopolymere. Provided the copolymers of propylene are statistical they generally contain up to 15% by weight, preferably up to 6% by weight, other alk-1-enes with up to 8 carbon atoms men, especially ethylene, but-1-ene or a mixture of ethylene and but-1-ene.

Block or impact copolymers of propylene are polymers in which, in the first stage, a propylene homopolymer or a random copolymer of propylene with up to 15% by weight, preferably up to 6% by weight, of other alk-1-enes produces up to 8 carbon atoms and then in the second stage a propylene-ethylene copolymer with ethylene contents of 15 to 80% by weight, the propylene-ethylene copolymer additionally containing further C ₄ -C ₈ -alk-1- may contain, polymerized. As a rule, so much of the propylene-ethylene copolymer is polymerized in that the copolymer produced in the second stage has a proportion of 3 to 60% by weight in the end product.

The polymerization for the production of polypropylene can be carried out using a Ziegler-Natta catalyst system. In doing so in particular those catalyst systems used in addition to a titanium-containing solid component a) or cocatalysts in the form of organic aluminum compounds b) and electron donor have connections c).

But catalyst systems based on metal can also be used ocenverbindungen or on the basis of polymerization active Metal complexes are used.

In particular, contain conventional Ziegler-Natta catalyst systems a titanium-containing solid component a) u. a. Halides or Alcohols of tri- or tetravalent titanium, also a halogen containing magnesium compound, inorganic oxides such as Silica gel as a carrier and electron donor compounds c). As such come in particular carboxylic acid derivatives and ketones, Ethers, alcohols or organosilicon compounds in question.

The titanium-containing solid component can be prepared in a manner known per se Methods are made. Examples include: a. in the EP-A 45 975, EP-A 45 977, EP-A 86 473, EP-A 171 200, GB-A-2 111 066, US-A 4 857 613 and US-A 5 288 824  described. What is known from DE-A 195 29 240 is preferred Procedure applied.

Suitable aluminum compounds b) are trialkyl aluminum also those compounds in which an alkyl group is replaced by a Alkoxy group or by a halogen atom, for example by Chlorine or bromine. The alkyl groups can be the same or be different from each other. There are linear or branched Alkyl groups into consideration. Trialkyl aluminum is preferred compounds used, the alkyl groups of 1 to 8 C- Have atoms, for example trimethyl aluminum, triethylalu minium, tri-iso-butyl aluminum, trioctyl aluminum or methyldi ethyl aluminum or mixtures thereof.

In addition to the aluminum compound b) is usually used as a further cocatalyst electron donor compounds c) such mono- or polyfunctional carboxylic acids, carboxylic anhydrides or carboxylic acid esters, furthermore ketones, ethers, alcohols, lactones, and organophosphorus and organosilicon compounds, the Electron donor compounds c) the same or different from the to produce the titanium-containing solid component a) set electron donor compounds can be.

Instead of Ziegler-Natta catalyst systems, too Metallocene compounds or polymerization-active metal complexes can be used to manufacture polypropylene.

Complex compounds of metals are said to be here under metallocenes of subgroups of the periodic table with organic ligands are understood that together with metallocenium ion-forming Compounds yield effective catalyst systems. For an one Metallocenkom are used to manufacture polypropylene plexes in the catalyst system usually before. As a carrier inorganic oxides are often used, but they can also organic carriers in the form of polymers, for example polyols fine use. The ones described above are preferred organic oxides that are also used to produce titanium-containing Solid component a) can be used.

Typically used metallocenes contain titanium, zirconium or hafnium as central atoms, zirconium being preferred. In general, the central atom is bonded via an n bond to at least one, usually substituted, cyclopentadienyl group and to further substituents. The further substituents can be halogens, hydrogen or organic radicals, fluorine, chlorine, bromine or iodine or a C ₁ -C ₁₀ alkyl group being preferred.

The cyclopentadienyl group can also be part of one appropriate heteroaromatic system.

Preferred metallocenes contain central atoms which have two identical or different π bonds to two substituted Cyclopentadienyl groups are attached, with particular emphasis on those are preferred in which substituents of the cyclopentadienyl group are bound to both cyclopentadienyl groups. In particular complexes are preferred, their substituted or unsubstituted Cyclopentadienyl groups additionally by cyclic groups two adjacent carbon atoms are substituted, the cycli groups also integrated in a heteroaromatic system could be.

Preferred metallocenes are also those that only have a substi contain or unsubstituted cyclopentadienyl group, which, however, is substituted with at least one radical which also is bound to the central atom.

Suitable metallocene compounds are, for example
Ethylenebis (indenyl) zirconium dichloride,
Ethylenebis (tetrahydroindenyl) zirconium dichloride,
Diphenylmethylene-9-fluorenylcyclopentadienylzirkoniumdichlorid,
Dimethylsilanediylbis (-3-tert.butyl-5-methylcyclopentadienyl) zirconium dichloride,
Dimethylsilanediyl (2-methyl-4-azapentalen) (2-methyl-4 (4'-methylphenyl) -indenyl) zirconium dichloride,
Dimethylsilanediyl (2-methyl-4-thiapentalen) (2-ethyl-4 (4'-tert.butylphenyl) -indenyl) zirconium dichloride,
Ethanediyl (2-ethyl-4-azapentalen) (2-ethyl-4 (4'-tert-butylphenyl) indenyl) zirconium dichloride,
Dimethylsilanediylbis (2-methyl-4-azapentalene) zirconium dichloride,
Dimethylsilanediylbis (2-methyl-4-thiapentalene) zirconium dichloride
Dimethylsilanediylbis (2-methylindenyl) zirconium dichloride,
Dimethylsilanediylbis (2-methylbenzindenyl) zirconium dichloride
Dimethylsilanediylbis (-2-methyl-4-phenylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methyl-4-naphthylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methyl-4-isopropylindenyl) zirconium dichloride or
Dimethylsilanediylbis (-2-methyl-4,6-diisopropylindenyl) zirconium dichloride and the corresponding dimethylzirconium compounds.

The metallocene compounds are either known or according to known methods available. For catalysis too Mixtures of such metallocene compounds are used, furthermore the metallocene complexes described in EP-A 416 815.

The metallocene catalyst systems also contain metal Compounds forming ocenium ions. Strong, neutral ones are suitable Lewis acids, ionic compounds with Lewis acid cations or Ionic compounds with Bronsted acids as the cation. Examples are tris (pentafluorophenyl) borane, tetrakis (pentafluoro phenyl) borate or salts of N, N-dimethylanilinium. Also ge Suitable as compounds forming metallocenium ions are open chain or cyclic alumoxane compounds. These will usually by reacting trialkyl aluminum with water produced and are usually different as mixtures long, both linear and cyclic chain molecules.

In addition, the metallocene catalyst systems can be metal organic compounds of the metals of I., II. or III. head Group of the periodic table contain such as n-butyl lithium, n-Bu tyl-n-octyl-magnesium or tri-iso-butyl aluminum, triethyl aluminum or trimethyl aluminum.

The production of the polypropylenes is carried out by polymerization in at least one, often also in two or more reaction zones connected in series (reactor cascade), in the gas phase, in a suspension or in a liquid phase (bulk phase). The usual reactors used for the polymerization of C ₂ -C ₈ -alk-1-enes can be used. Suitable reactors include continuously operated Rührkes sel, loop reactors or fluidized bed reactors. The size of the reactors is not essential. It is based on the output that is to be achieved in or in the individual reaction zones.

In particular, fluidized bed reactors and horizontally or vertically stirred powder bed reactors are used as reactors. The reaction bed generally consists of the polymer of C ₂ -C ₈ -alk-1-enes, which is polymerized in the respective reactor.

The polymerization to produce the polypropylenes used under normal reaction conditions at temperatures of 40 up to 120 ° C, in particular from 50 to 100 ° C and pressures from 10 to 100 bar, in particular from 20 to 50 bar.  

Suitable polypropylenes generally have a melt flow rate (MFR), according to ISO 1133, from 0.1 to 200 g / 10 min., In particular from 0.2 to 100 g / 10 min., At 230 ° C and under a weight of 2.16 kg.

Polyethylene homopolymers are particularly preferred low density (PE-LD) and polypropylene homopolymer.

In the process of making polyolefins According to the invention, the light stabilizers selected from the one initially mentioned compounds a) to d). "Connections" is said to be Compound class can be understood, that is, as a class of Individual compounds.

The compounds a) are cyanoacrylic acid esters of the formula I.

With
R ^I and R ^{II are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cyclo alkenyl, C ₁ -C ₁₂ alkoxy, aryl, heteroaryl, optionally substituted,
X ethyl, 2-ethylhexyl, pentaerythrityl, propane-1,2,3-triyl, polyalkylene glycol residue.
n integer from 0 to 3,
m integer from 1 to 4.

Preferably n = 0, i.e. H. the aromatic systems are unsubsti advantage. M is preferably 1 or 4.

For m = 1, X is preferably ethyl or 2-ethylhexyl. The individual compound a1) results from formula I with n = 0, m = 1 and X = ethyl:

commercially available e.g. B. as Univul® 3035 from BASF.

For m = 4, X is preferably pentaerythrityl, which is derived from pentaerythritol

derives. From formula I with n = 0, m = 4 and X = pentaerythrityl the individual compound a2) results:

commercially available e.g. B. as Uvinul® 3030 from BASF.

The individual compound a3) results from formula I with n = 0, m = 1 and X = 2-ethylhexyl:

commercially available e.g. B. as Univul® 3039 from BASF.

For m = 3, X is preferably propane-1,2,3-tiyl, which is derived from glycerol

derives.

Preferred polyalkylene glycol radicals X are derived from the formula

from, where R ^I and R ^{II have} the meaning already defined.

The 2-cyanoacrylic acid esters a) of the formula I are preferably obtained by reacting cyanoacetic acid esters of the general formula Ia

with n mol of a compound (Ib)

with T = O or NH under the conditions of the Knoevenagel condensate tion available. The implementation can e.g. B. in aromatic solution agents such as toluene or xylene (see e.g. Organikum, 19th edition, Verlag Barth Leipzig 1993, p. 476). Be however, preference is given to polar organic solvents such as Dimethylformamide, dimethylacetamide, N-methylpyrrolidone, trialkyl orthoformate or alcohols such as n-propanol, n-butanol, ethylene glycol, diethylene glycol, ethylene glycol monomethyl ether, cyclo hexanol or similar compounds used. Form the use starting compounds can already be a liquid mixture an additional solvent can be dispensed with. The Reaction temperatures are preferably between 20 and 180 ° C, be particularly preferably between 40 and 150 ° C. Printing is preferred normal atmospheric pressure. Depending on the reactivity the compound Ib used is the use of a catalyst tors or a catalyst mixture advantageous. As Catalysts are suitable for. B. ammonium acetate, piperidine and β-alanine and its acetates.

In the case of very long reaction times, Lewis acids such as AlCl ₃ , ZrCl ₄ , TiCl ₄ or, above all, ZnCl ₂ can also be used as catalysts for the reaction in the amounts customary for this.

The cyanoacetic esters Ia can, for example, by reacting cyanoacetic acid or its esters with the corresponding polyols X (OH) _n in the presence of a catalyst such as boric acid, p-toluenesulfonic acid, Na ₂ CO ₃ or K ₂ CO ₃ or tetrabutyl orthotitanate, preferably in toluene or xylene getting produced.

Compounds b) are 4,4-diarylbutadienes of the formula II

in which the diene system in the Z, Z; Z, E; E, Z or E, E configuration or a mixture thereof and in which the variables have the following meaning independently of one another:
R ¹ and R ^{2 are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₁ -C ₁₂ alkoxy, C ₁ -C ₂₀ alkoxy carbonyl, C ₁ -C ₁₂ alkylamino, C ₁ -C ₁₂ dialkylamino, aryl, heteroaryl, optionally substituted, water-solubilizing substituents selected from the group consisting of carboxylate, sulfonate or ammonium radicals;
R ³ hydrogen, COOR ⁵ , COR ⁵ , CONR ⁵ R ⁶ , CN, O = S (-R ⁵ ) = O, O = S (-OR ⁵ ) = O, R ⁷ OP (-OR ⁸ ) = O, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₇ -C ₁₀ bicyclo alkenyl, aryl , Heteroaryl, optionally substituted;
R ⁴ COOR ⁶ , COR ⁶ , CONR ⁵ R ⁶ , CN, O = S (-R ⁶ ) = O, O = S (-OR ⁶ ) = O, R ⁷ OP (-OR ⁸ ) = OC ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₁ -C ₁₀ cycloalkenyl, C ₇ -C ₁₀ bicyclo alkenyl, aryl, heteroaryl, if appropriate substituted;
R ⁵ to R ^{8 are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₇ -C ₁₀ bicycloalkenyl, aryl, heteroaryl, optionally substituted;
n 1 to 3,
wherein the variables R ³ to R ⁸ together, in each case together with the carbon atoms to which they are attached, can together form a 5- or 6-ring, which can optionally be fused further.

Preferred compounds of the formula II are those in which
R ¹ and R ² independently of one another hydrogen, C ₁ -C ₁₂ alkyl, C ₁ -C ₈ alkoxy, C ₁ -C ₁₂ alkylamino, C ₁ -C ₁₂ dialkylamino, water-solubilizing substituents selected from the group consisting of from carboxylate, sulfonate or ammonium residues;
R ^{3 is} hydrogen, COOR ⁵ , COR ⁵ , CONR ⁵ R ⁶ , CN, C ₁ -C ₁₂ alkyl, C ₃ -C ₆ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, phenyl, naphthyl, thienyl, optionally substituted;
R ⁴ COOR ⁶ , COR ⁶ , CONR ⁵ R ⁶ , CN, C ₁ -C ₁₂ alkyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, phenyl, naphthyl, thienyl, optionally substituted;
R ⁵ and R ^{6 are} independently hydrogen, C ₁ -C ₁₂ alkyl, C ₃ -C ₆ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, phenyl, naphthyl, optionally substituted,
n 1 to 3
means.

As C ₁ -C ₁₂ alkyl radicals for R ¹ to R ^{6 are} particularly preferably methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, n- Pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl, 2-ethylhexyl. Cycloalkyl radicals for R ³ to R ^{6 are} particularly preferred branched or unbranched cyclopentyl and cyclohexyl.

Suitable mono- or dialkylamino radicals for R ¹ and R ^{2 are} particularly preferably methyl, ethyl, n-propyl, n-butyl, 2-methylpropyl, 1,1-dimethylpropyl, 2-ethylhexyl. As bicycloalkyl radicals for R ³ to R ⁶ camphor derivatives are particularly preferred.

The substituents R ¹ and R ² can each be bound in the ortho, meta and / or para position on the aromatic. In the case of disubstituted aromatics (n = 2), R ¹ and R ^{2 can be} in the ortho / para or meta / para position. Compounds of the formula II with n = 1 are preferred in which R ¹ is R ² and both radicals are in the para position.

Furthermore, particular preference is given to compounds of the formula II in which R ³ or R ^{4 may} not be H, CN, C ₁ -C ₂₀ -alkyl, C ₂ -C ₁₀ -alkenyl, aryl, He teroaryl, optionally substituted, if R ⁴ or R ^{3 means} COOR ⁵ or COOR ⁶ .

Compounds of the formula II and n = 1 with the following substituents are very particularly preferred:

The connections b) can be done according to the equation

produce by condensation, where R ¹ to R ^{4 have} the meaning already mentioned.

The above-mentioned condensation can be catalyzed by either base or acid. Suitable catalysts are:
tertiary amines, such as. B. pyridine, morpholine, triethylamine, triethanolamine;
secondary amines, such as. B. piperidine, dimethylamine, diethylamine; NH ₃ , NaNH ₂ , KNH ₂ , NH ₄ OAC;
basic aluminum oxide, basic ion exchanger;
Na ₂ CO ₃ , K ₂ CO ₃ ;
acidic catalysts, such as. B. glacial acetic acid, formic acid, propionic acid;
HCl, H ₂ SO ₄ , HNO ₃ ;
acidic ion exchanger.

The amount of the catalysts is generally 0.1 to 50 mol%, preferably 0.5 to 20 mol%, of the amount of the used Aldehyde. Preferably one works at temperatures from 20 to 150 ° C, particularly 30 to 100 ° C, particularly preferably 40 to 80 ° C. Special printing conditions are not required  Lich; in general, the reaction is carried out at atmospheric pressure in front. Alcohols such as. B. Methanol, Etha nol or isopropanol; Aromatics such as B. toluene or xylene; Koh hydrogen oils, for example heptane or hexane; chlorinated Hydrocarbons such as B. chloroform or dichloromethane; mig lyol, tetrahydrofuran can be used. The reaction can can also be carried out without solvents.

It is also possible, starting from methyl or ethyl esters, to produce longer-chain esters by transesterification reactions in the presence of a basic catalyst. Suitable catalysts for the transesterification are:
basic alkali and alkaline earth salts, preferably those which are neither soluble in the educts nor in the products and can be easily separated off after the end of the reaction, particularly preferably: sodium, potassium or calcium carbonate or sodium hydrogen carbonate;
Alkaline earth oxides, preferably calcium or magnesium oxide and basic zeolites.

The amount of the catalysts is generally 1 to 80 mol%, preferably 5 to 50 mol%, of the amount of the used Ester. The amount of alcohol used must be at least equimo be lar to the amount of starting ester used. Preferred who the amounts of 200 to 500 mol% of the alcohol used. The Ent Removal of the methanol or ethanol formed by distillation. It is preferred to work at temperatures of 50 up to 250 ° C, especially 60 to 150 ° C. Special conditions regarding pressure is not required; generally you take that Implementation at atmospheric pressure before. As a solvent in este, higher-boiling compounds such as xylenes, but also toluene or mixtures of the alcohols used with liquid, short ketti gene alkanes such as hexane and heptane can be used. Prefers you work solvent-free in the alcohol used. The Transesterification can be carried out batchwise or continuously be performed. When driving continuously the reactants are preferably removed from a fixed bed insoluble base.

In the event that R ³ ≠ R ⁴ , the compounds of formula I can in principle in their various geometric isomers, ie with a Z, Z; Z, E; E, Z and / or E, E-configured service system. The all-E and / or all-Z isomers are preferred as light stabilizers, and the all-E isomers are very particularly preferred. If R ³ = R ⁴ , the C = C double bond between C-3 and C-4 (in the vicinity of the diaryl system) can be in the E and / or Z configuration, preferably in the Z configuration.

The compounds c) are benzophenones of the formula III

With
Y is hydrogen, COOR ^I or OH, Z OR ^I or

A is hydrogen or SO ₃ H, where R ^I and R ^{II have} the meaning given in a).

Y is preferably hydrogen, or A = hydrogen, or Y and A. both equal hydrogen.

Preferably R ^I = C ₁ -C ₂₀ alkyl, or R ^II = C ₁ -C ₂₀ alkyl, or R ^I and R ^II both equal C ₁ -C ₂₀ alkyl.

Z = OR ^I is particularly preferred. For Z = OR ^I , R ^{I is} particularly preferably C ₆ -C ₁₀ alkyl and very particularly preferably octyl. The individual compound c1) results from formula I with Y = H, A = H, Z = OR ^I and R ^I = octyl:

commercially available e.g. B. as Uvinul® 3008 from BASF.

The compounds c) are prepared, for. B. as described in DE-A 21 42 593.  

Compounds d) are cinnamic acid esters of the formula IV

where R ^I , R ^II and n have the meaning given in a).

Preferably n = 1 and R ^I = C ₁ -C ₁₂ alkoxy. R ^II = C ₁ -C ₂₀ alkyl is likewise preferred.

N = 1 and R ^I = C ₁ -C ₃ alkoxy are particularly preferred, in particular R ^I = OCH ₃ .

R ^II = C ₆ -C ₁₀ alkyl, in particular C ₈ alkyl, very particularly preferably 2-ethylhexyl, is particularly preferred.

Formula IV with n = 1, R ^I = OCH ₃ and R ^II = 2-ethyl hexyl gives the individual compound d1):

commercially available e.g. B. as Uvinul® 3088 from BASF.

The compounds d) are prepared in a conventional manner by esterification of the corresponding cinnamic acid

with the corresponding alcohol R ^II -OH, usually with acid catalysis and removal of the water of reaction split off.

Likewise, the compounds d) can be prepared by the process described in EP-A 490 198: in a first reaction stage, a dialkyl ketal of an aromatic aldehyde of the formula is used

with chains of the formula CH ₂ = C = O in the presence of a Lewis or proto-acid as a catalyst to a 3-arylpropionic acid derivative of the formula

around. This intermediate is reacted in a second stage in the presence of acid or base and the corresponding alcohol R ^II -OH with elimination of the alcohol R ^a -OH to give compound d) of the formula (IV).

The individual compounds mentioned are a1), a2), a3), c1) and d1) particularly preferred.

It is understood that from each of the connection classes a) to d) more than a single connection can be selected, and that one also uses light stabilizers made of two or more of the compounds classes a) to d) can use together. So it can mixtures of different light stabilizers are also used the.

The light stabilizers are preferably added to the polyolefin an amount of 0.005 to 10, in particular 0.01 to 5, and esp more preferably 0.05 to 2 wt .-% added. Very particularly preferred the amount is 0.1 to 1% by weight. Obtain these quantities i refer to the stabilized polyolefin (polyolefin + sum of all Light stabilizers a) to d)). Becomes more than a light stabilizer used, the quantities refer to the sum of all light stabilizers.

In addition to the light stabilizers from the compound classes a) to d), further stabilizers can be added to the polyolefin, selected from groups a ') to x'):

• 1. a ') alkylated monophenols,
• 2. b ') alkylthiomethylphenols,
• 3. c ') hydroquinones and alkylated hydroquinones,
• 4. d ') tocopherols,  
• 5. e ') hydroxylated diphenyl thioethers,
• 6. f ') alkylidene bisphenols,
• 7. g ') O-, N- and S-benzyl compounds,
• 8. h ') aromatic hydroxybenzyl compounds,
• 9. i ') triazine compounds,
• 10. j ') benzylphosphonates,
• 11. k ') acylaminophenols,
• 12. l ') esters of β- (3,5-di-tert-butyl-4-hydroxyphenyl) propion acid, β- (5-tert-butyl-4-hydroxy-3-methylphenyl) propion acid, (3- (3,5-dicyclohexyl-4-hydroxyphenyl) propionic acid and 3,5-di-tert-butyl-4-hydroxyphenyl-acetic acid,
• 13. m ') amides of β- (3,5-Dz-tert-butyl-4-hydroxyphenyl) propion acid,
• 14. n ') ascorbic acid and its derivatives,
• 15. o ') antioxidants based on amine compounds,
• 16. p ') phosphites and phosphonites,
• 17. q ') 2- (2'-hydroxyphenyl) benzotriazoles,
• 18. r ') sulfur-containing peroxide scavenger or sulfur-containing anti oxidants
• 19. s') 2-hydroxybenzophenones,
• 20. t ') esters of unsubstituted and substituted benzoic acid,
• 21. u ') acrylates,
• 22. v ') sterically hindered amines,
• 23. w ') oxamides and
• 24. x ') 2- (2-hydroxyphenyl) -1,3,5-triazines.

Group a ') of the alkylated monophenols includes, for example 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethyl phenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclo pentyl-4-methylphenol, 2- (α-methylcyclohexyl) -4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol, 2, 6-di-tert-butyl-4-methoxymethylphenol, nonylphenols, which have a linear or branched side chain, for example 2,6-di-nonyl-4-methylphenol, 2,4-dimethyl-6- (1'-methylundec-1'- yl) phenol, 2,4-dimethyl-6- (1'-methylheptadec-1'-yl) phenol, 2,4-dimethyl-6- (1'-methyltridec-1'-yl) phenol and mixtures of these connections.

Group b ') of the alkylthiomethylphenols includes, for example 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl 6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol and 2,6-di dodecylthiomethyl-4-nonylphenol.

To group c ') of the hydroquinones and alkylated hydroquinones include, for example, 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di tert-butyl hydroquinone, 2,5-di-tert-amyl hydroquinone, 2,6-diphenyl  4-octadecyloxyphenol, 2,6-di-tert-butylhydroquinone, 2,5-di-tert butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenyl stearate and bis- (3,5-di-tert butyl-4-hydroxyphenyl) adipate.

Group d ') of the tocopherols includes, for example, α-toco pherol, β-tocopherol, γ-tocopherol, δ-tocopherol and mixtures these compounds, as well as tocopherol derivatives, such as Tocopheryl acetate, succinate, nicotinate and polyoxyethylene succi nat ("Tocofersolan").

Group e ') of the hydroxylated diphenylthioethers include for example 2,2'-thiobis (6-tert-butyl-4-methylphenol), 2,2'-thiobis (4-octylphenol), 4,4'-thiobis (6-tert-butyl-3-methyl phenol), 4,4'-thiobis (6-tert-butyl-2-methylphenol), 4,4'-thio bis- (3,6-di-sec-amylphenol) and 4,4'-bis (2,6-dimethyl-4-hydroxy phenyl) disulfide.

Group f ') of the alkylidene bisphenols include, for example 2,2'-methylenebis (6-tert-butyl-4-methylphenol), 2,2'-methylenebis (6-tert-butyl-4-ethylphenol), 2,2'-methylenebis [4-methyl-6- (α methylcyclohexyl) phenol], 2,2'-methylenebis (4-methyl-6-cyclohexyl phenol), 2,2'-methylenebis (6-nonyl-4-methylphenol), 2,2'-methylene bis (4,6-di-tert-butylphenol), 2,2-ethylidenebis (4,6-di-tert-butyl- phenol), 2,2'-ethylidenebis (6-tert-butyl-4-isobutylphenol), 2,2'-methylenebis [6- (α-methylbenzyl) -4-nonylphenol], 2,2'-methylenebis [6- (α, α-dimethylbenzyl) -4-nonylphenol], 4,4'-methylenebis (2,6-di-tert-butylphenol), 4,4'-methylenebis (6-tert-butyl-2-methylphenol), 1,1-bis (5-tert-butyl-4-hydroxy- 2-methylphenyl) butane, 2,6-bis (3-tert-butyl-5-methyl-2-hydroxy benzyl) -4-methylphenol, 1,1,3-tris (5-tert-butyl-4-hydroxy-2- methylphenyl) butane, 1,1-bis (5-tert-butyl-4-hydroxy-2-methyl phenyl) -3-n-dodecyl mercaptobutane, ethylene glycol bis [3,3-bis (3'- tert-butyl-4'-hydroxyphenyl) butyrate, bis (3-tert-butyl-4-hydroxy- 5-methylphenyl) dicyclopentadiene, bis [2- (3'-tert-butyl-2'- hydroxy-5'-methylbenzyl) -6-tert-butyl-4-methylphenyl] - terephthalate, 1,1-bis (3,5-dimethyl-2-hydroxyphenyl) butane, 2,2-bis (3,5-di-tert-butyl-4-hydroxyphenyl) propane, 2,2-bis (5- tert-butyl-4-hydroxy-2-methylphenyl) -4-n-dodecyl mercaptobutane and 1,1,5,5-tetrakis (5-tert-butyl-4-hydroxy-2-methylphenyl) pentane.

Group g ') of the O-, N- and S-benzyl compounds include for example 3,5,3 ', 5'-tetra-tert-butyl-4,4'-dihydroxydibenzyl ether, octadecyl-4-hydroxy-3, 5-dimethylbenzylmercaptoacetate, Tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, Tris (3,5-di-tert-butyl-4-hydroxybenzyl) amine, bis (4-tert butyl-3-hydroxy-2, 6-dimethylbenzyl) dithioterephthalate,  Bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide and isooctyl-3,5- di-tert-butyl-4-hydroxybenzylmercaptoacetate.

Group h ') of the aromatic hydroxybenzyl compounds for example 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) - 2,4,6-trimethylbenzene, 1,4-bis (3,5-di-tert-butyl-4-hydroxy benzyl) -2,3,5,6-tetramethylbenzene and 2,4,6-tris (3,5-di-tert butyl-4-hydroxybenzyl) phenol.

Group i ') of the triazine compounds includes, for example 2,4-bis (octylmercapto) -6- (3,5-di-tert-butyl-4-hydroxyanilino) - 1,3,5-triazine, 2-octylmercapto-4,6-bis (3,5-di-tert-butyl-4- hydroxyanilino) -1,3,5-triazine, 2-octylmercapto-4,6-bis (3,5-di tert-butyl-4-hydroxyphenoxy) -1,3,5-triazine, 2,4,6-tris (3,5-di tert-butyl-4-hydroxyphenoxy) -1,2,3-triazine, 1,3,5-tris (3,5-di tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-tert butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 2,4,6-tris (3,5- di-tert-butyl-4-hydroxyphenylethyl) -1,3,5-triazine, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxyphenylpropionyl) -hexahydro-1,3,5-tri azine, 1,3,5-tris (3,5-dicyclohexyl-4-hydroxybenzyl) isocyanurate and 1,3,5-tris (2-hydroxyethyl) isocyanurate.

Group j ') of the benzylphosphonates include, for example Dimethyl-2,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, dioctadecyl-3,5-di tert-butyl-4-hydroxybenzylphosphonate and dioctadecyl-5-tert butyl-4-hydroxy-3-methylbenzylphosphonate.

The group k ') of the acylaminophenols includes, for example 4-hydroxylauroylanilide, 4-hydroxystearoylanilide and Octyl-N- (3,5-di-tert-butyl-4-hydroxyphenyl) carbamate.

The esters of propionic and acetic acid mentioned in group 1 ') Derivatives are based on mono- or polyhydric alcohols such as for example methanol, ethanol, n-octanol, i-octanol, octa decanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propane diol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, Triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N, N'-bis (hydroxyethyl) oxamide, 3-thiaundecanol, 3-thiapenta decanol, trimethylhexanediol, trimethylolpropane and 4-hydroxy methyl-1-phospha-2,6,7-trioxabicyclo [2.2.2] octane.

The amides of the propionic acid derivative mentioned in group m ') gene amine derivatives such as N, N'-bis (3,5-di tert-butyl-4-hydroxyphenylpropionyl) hexamethylenediamine, N, N'-  Bis (3,5-di-tert-butyl-4-hydroxyphenylpropionyl) -trimethylenediamine and N, N'-bis (3,5-di-tert-butyl-4-hydroxyphenylpropionyl) hydrazine.

In addition to ascorbic acid (vitamin C), group n ') also includes Ascorbic acid derivatives such as ascorbyl palmitate, laurate and stearate and ascorbyl sulfate and phosphate.

To group o ') of antioxidants based on amine compounds include, for example, N, N'-di-isopropyl-p-phenylenediamine, N, N'-di-sec-butyl-p-phenylenediamine, N, N'-bis (1,4-dimethylpentyl) - p-phenylenediamine, N, N'-bis (1-ethyl-3-methylpentyl) -p-phenylene diamine, N, N'-bis (1-methylheptyl) -p-phenylenediamine, N, N'-dicyclo hexyl-p-phenylenediamine, N, N'-diphenyl-p-phenylenediamine, N, N'-bis (2-naphthyl) -p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylene diamine, N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine, N- (1-methylheptyl) -N'-phenyl-p-phenylenediamine, N-cyclohexyl-N'- phenyl-p-phenylenediamine, 4- (p-toluenesulfamoyl) diphenylamine, N, N'-dimethyl-N, N'-di-sec-butyl-p-phenylenediamine, diphenylamine, N-allyldiphenylamine, 4-isopropoxydiphenylamine, N-phenyl-1- naphthylamine, N- (4-tert-octylphenyl) -1-naphthylamine, N-phenyl-2- naphthylamine, octyl-substituted diphenylamine, such as wise p, p'-di-tert-octyldiphenylamine, 4-n-butylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylamino- phenol, 4-octadecanoylaminophenol, bis [4-methoxyphenyl] amine, 2,6-di-tert-butyl-4-dimethylaminomethylphenol, 2,4-diaminodi phenylmethane, 4,4'-diaminodiphenylmethane, N, N, N ', N'-tetramethyl- 4,4'-di-aminidiphenylmethane, 1,2-bis [(2-methylphenyl) amino] ethane, 1,2-bis (phenylamino) propane, (o-tolyl) biguanide, bis [4- (1 ', 3'-di methylbutyl) phenyl] amine, tert-octyl substituted N-phenyl-1- naphthylamine, a mixture of mono- and dialkylated tert butyl / tert-octyldiphenylamine, a mixture of mono- and dialkylated nonyldiphenylamine, a mixture of mono- and dialkylated dodecyldiphenylamine, a mixture of mono- and dialkylated isopropyl / isohexyldiphenylamine, a mixture of mono- and dialkylated tert-butyldiphenylamine, 2,3-dihydro-3,3- dimethyl-4H-1,4-benzothiazine, phenothiazine, a mixture of mono- and dialkylated tert-butyl / tert-octylphenothiazine, a Mixture of mono- and dialkylated tert-octylphenothiazine, N-allylphenothiazine, N, N, N ', N'-tetraphenyl-1,4-diaminobut-2-ene, N, N-bis (2,2,6,6-tetramethylpiperidin-4-yl) hexamethylenediamine, Bis (2,2,6,6-tetramethylpiperidin-4-yl) sebacate, 2,2,6,6-tetra methylpiperidin-4-one and 2,2,6,6-tetramethylpiperidin-4-ol.

The group p ') of the phosphites and phosphonites include, for example white triphenyl phosphite, diphenylalkyl phosphite, phenyl dialkyl phosphite, tris (nonylphenyl) phosphite, trilauryl phosphite, triocta decylphosphite, distearylpentaerythritol diphosphite, tris (2,4-di-  tert-butylphenyl) phosphite, diisodecylpentaerythritol diphosphite, Bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, Bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, Diisodecyloxypentaerythritol diphosphite, bis (2,4-di-tert butyl-6-methylphenyl) pentaerythritol diphosphite, bis (2,4,6-tris (tert-butylphenyl)) - pentaerythritol diphosphite, tristearylsorbi tol triphosphite, tetrakis (2,4-di-tert-butylphenyl) -4,4'-bipheny lendiphosphonite, 6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-di benz- [d, g] -1,3,2-dioxaphosphocin, 6-fluoro-2,4.8,10-tetra-tert butyl-12-methyl-dibenz [d, g] -1,3,2-dioxaphosphocin, bis (2,4-di tert-butyl-6-methylphenyl) methyl phosphite and bis (2,4-di-tert-bu tyl-6-methylphenyl) - ethyl phosphite.

Group q ') of 2- (2'-hydroxyphenyl) benzotriazoles includes, for example, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (3', 5'-di-tert-butyl-2 '-hydroxyphenyl) benzotriazole, 2- (5'-tert-butyl-2'-hydroxyphenyl) benzotriazole, 2- (2'-hydroxy-5' - (1,1,3,3-tetramethylbutyl) phenyl) benzotriazole, 2- (3 ', 5'-di-tert-butyl-2'-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3'-tert-butyl-2'-hydroxy-5'-methylphenyl) -5- chloro-benzotriazole, 2- (3'-sec-butyl-5'-tert-butyl-2'-hydroxyphenyl) benzotriazole, 2- (2'-hydroxy-4'-octyloxyphenyl) benzotriazole, 2- (3 ' , 5'-di-tert-amyl-2'-hydroxyphenyl) benzotriazole, 2- (3 ', 5'-bis (α, α-dimethylbenzyl) -2'-hydroxyphenyl) benzotriazole, a mixture of 2 - (3'-Tert-butyl-2'-hydroxy-5 '- (2-octyloxycarbonylethyl) phenyl) -5-chlorobenzotriazole, 2- (3'-tert-butyl-5' - [2- (2nd -ethylhexyloxy) -carbonylethyl] - 2'-hydroxyphenyl) -5-chloro-benzotriazole, 2- (3'-tert-butyl-2'-hydroxy-5 '- (2-methoxycarbonylethyl) phenyl) -5-chloro-benzotriazole , 2- (3'-tert-butyl-2'-hydroxy-5 '- (2-methoxycarbony ethyl) phenyl) benzotriazole, 2- (3'-tert-butyl-2'-hydroxy-5 '- (2-octyloxycarbonyl ethyl) phenyl) benzotriazole, 2- (3'-tert-butyl-5' - [ 2- (2-ethylhexyl oxy) carbonylethyl] -2'-hydroxyphenyl) benzotriazole, 2- (3'-dodecyl-2'-hydroxy-5'-methylphenyl) benzotriazole and 2- (3'-tert-butyl- 2'-hydroxy-5 '- (2-isooctyloxycarbonylethyl) phenylbenzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6-benzotriazol-2-ylphenol]; the product of the complete esterification of 2- [3'-tert-butyl-5 '- (2-methoxycarbonylethyl) -2'-hydroxyphenyl] - 2H-benzotriazole with polyethylene glycol 300; [R-CH ₂ CH ₂ -COO (CH ₂ ) _{3 2} , with R = 3'-tert-butyl-4'-hydroxy-5'-2H-benzotriazol-2-ylphenyl.

To group r ') of the sulfur-containing peroxide scavenger or sulfur containing antioxidants include z. B. Esters of 3,3'-thiodipropion acid, for example the lauryl, stearyl, myristyl or Tridecyl ester, mercaptobenzimidazole or the zinc salt of  2-mercaptobenzimidazole, zinc dibutyldithiocarbamate, dioctadecyldi sulfide and pentaerythritol tetrakis (β-dodecylmercapto) propionate.

The group s') of the 2-hydroxybenzophenones include, for example the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decyloxy, 4-dodecyl oxy-, 4-benzyloxy-, 4,2 ', 4'-trihydroxy and 2'-hydroxy-4,4'-dime thoxy derivatives.

To group t ') the esters of unsubstituted and substituted Benzoic acid includes, for example, 4-tert-butylphenyl salicylate, Phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, Bis (4-tert-butylbenzoyl) resorcinol, benzoylresorcinol, 2,4-di tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl-3,5-di-tert-butyl- 4-hydroxybenzoate and 2-methyl-4,6-di-tert-butylphenyl-3,5-di tert-butyl-4-hydroxybenzoate.

The group u ') of the acrylates includes, for example, ethyl-α-cyano- β, β-diphenyl acrylate, isooctyl-α-cyano-β, β-diphenyl acrylate, methyl α-methoxycarbonylcinnamate, methyl-α-cyano-β-methyl-p-methoxy cinnamate, butyl-α-cyano-β-methyl-p-methoxycinnamate and methyl-α- methoxycarbonyl-p-methoxycinnamate.

Group v ') of the sterically hindered amines include, for example wise bis (2,2,6,6-tetramethylpiperidin-4-yl) sebacate, bis (2,2,6,6- tetramethylpiperidin-4-yl) succinate, bis (1,2,2,6,6-pentamethylpi peridin-4-yl) sebacate, bis (1-octyloxy-2,2,6,6-tetramethylpipe ridin-4-yl) sebacate, bis (1, 2,2,6,6-pentamethylpiperidin-4-yl) -n butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensate onproduct from 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-hydroxy piperidine and succinic acid, the condensation product of N, N'- Bis (2,2,6,6-tetramethylpiperidin-4-yl) hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, Tris (2,2,6,6-tetra methylpiperidin-4-yl) nitrilotriacetate, tetrakis (2,2,6,6-tetra methylpiperidin-4-yl) -1,2,3,4-butane tetracarboxylate, 1,1 '- (1,2- Ethylene) -bis (3,3,5,5-tetramethylpiperazinone), 4-benzoyl-2,2,6,6- tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, Bis (1,2,2,6,6-pentamethylpiperidin-4-yl) -2-n-butyl-2- (2-hydroxy- 3,5-di-tert-butylbenzyl) malonate, 3-n-octyl-7,7,9,9-tetramethyl- 1,3,8-triazaspiro [4.5] decan-2,4-dione, bis (1-octyloxy-2,2,6,6- tetramethylpiperidin-4-yl) sebacate, bis (1-octyloxy-2,2,6,6-tetra methylpiperidin-4-yl) succinate, the condensation product of N, N'- Bis- (2,2,6,6-tetramethylpiperidin-4-yl) hexamethylenediamine and 4-Morpholino-2,6-dichloro-1,3,5-triazine, the condensation product from 2-chloro-4,6-bis (4-n-butylamino-2,2,6,6-tetramethylpiperidine- 4-yl) -1,3,5-triazine and 1,2-bis (3-aminopropylamino) ethane, the Condensation product from 2-chloro-4,6-di- (4-n-butylamino-  1,2,2,6,6-pentamethylpiperidin-4-yl) -1,3,5-triazine and 1,2-bis (3-aminopropylamino) ethane, 8-acetyl-3-dodecyl-7,7,9,9- tetramethyl-1,3,8-triazaspiro [4.5] -decane-2,4-dione, 3-dodecyl-1- (2,2,6,6-tetramethylpiperidin-4-yl) pyrrolidin-2,5-dione, 3-dodecyl-1- (1, 2,2,6,6-pentamethylpiperidin-4-yl) pyrrolidine 2,5-dione, a mixture of 4-hexadecyloxy and 4-stearyl oxy-2,2,6,6-tetramethylpiperidine, the condensation product N, N'-bis (2,2,6,6-tetramethylpiperidin-4-yl) hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, the condensate onproduct from 1,2-bis (3-aminopropylamino) ethane and 2,4,6-tri chloro-1,3,5-triazine, 4-butylamino-2,2,6,6-tetramethylpiperidine, N- (2,2,6,6-tetramethylpiperidin-4-yl) -n-dodecylsuccinimide, N- (1,2,2,6,6-pentamethyl-4-yl) -n-dodacylsuccinimid, 2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxospiro [4.5] - decane, the condensation product from 7,7,9,9-tetramethyl-2-cyclo- undecyl-1-oxa-3,8-diaza-4-oxospiro- [4.5] decane and epichlorohydrin, the condensation products from 4-amino-2,2,6,6-tetramethyl piperidine with tetramethylolacetylene diureas and poly (meth oxypropyl-3-oxy) - [4- (2,2,6,6-tetramethyl) piperidinyl] siloxane.

The group w ') of the oxamides include, for example, 4,4'-dioctyl oxyoxanilide, 2,2'-diethoxyoxanilide, 2,2'-dioctyloxy-5,5'-di tert-butoxanilide, 2,2'-didodecyloxy-5,5'-di-tert-butoxanilide, 2-ethoxy-2'-ethyloxanilide, N, N'-bis (3-dimethylaminopropyl) oxamide, 2-ethoxy-5-tert-butyl-2'-ethoxanilide and its mixture with 2-ethoxy-2'-ethyl-5,4'-di-tert-butoxanilide and mixtures of ortho-, para-methoxy-disubstituted oxanilides and mixtures of ortho and para-ethoxy disubstituted oxanilides.

The group x ') of 2- (2-hydroxyphenyl) -1,3,5-triazines include for example 2,4,6-tris (2-hydroxy-4-octyloxyphenyl) -1,3,5-tri azine, 2- (2-hydroxy-4-octyloxyphenyl) -4,6-bis (2,4-dimethylphe nyl) -1,3,5-triazine, 2- (2,4-dihydroxyphenyl) -4,6-bis (2,4-dimethyl phenyl) -1,3,5-triazine, 2,4-bis (2-hydroxy-4-propyloxyphenyl) -6- (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-octyloxy phenyl) -4,6-bis (4-methylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4- dodecyloxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-tridecyloxyphenyl) -4,6-bis (2,4-dimethylphenyl) - 1,3,5-triazine, 2- [2-hydroxy-4- (2-hydroxy-3-butyloxypropoxy) - phenyl] -4,6-bis (2,4-dimethyl) -1,3,5-triazine, 2- [2-hydroxy-4- (2- hydroxy-3-octyloxy-propoxy) phenyl] -4,6-bis (2,4-dimethyl) - 1,3,5-triazine, 2- [4- (dodecyloxy / tridecyloxy-2-hydroxypropoxy) - 2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [2-hydroxy-4- (2-hydroxy-3-dodecyloxy-propoxy) phenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-hexyloxy phenyl) -4,6-diphenyl-1,3,5-triazine, 2- (2-hydroxy-4-methoxy phenyl) -4,6-diphenyl-1,35-triazine, 2,4,6-tris [2-hydroxy-4-  (3-butoxy-2-hydroxypropoxy) phenyl) -1,3,5-triazine and 2- (2-hydroxyphenyl) -4- (4-methoxyphenyl) -6-phenyl-1,3,5-triazine.

The mentioned further stabilizers from groups a ') to x') are used in usual amounts, especially in amounts of 0.001 to 1 wt .-%, based on that with the light stabilizers a) to d) and the further stabilizers a ') to x') stabili based polyolefin.

In the method according to the invention, the light stabilization sators and, if available, the other stabilizers, the Polyolefin added. The addition takes place in the usual way. So you can the light stabilizers and possibly the other Stabilisa gates to the starting monomer (olefin monomers) and the Polymerize mixture of monomers and stabilizers. As well can the stabilizers during the polymerization of the oils Add finmonomeric. Requirement for an addition before or during rend of the polymerization is that the stabilizers in the poly merization conditions are stable, i.e. not or only we nig decompose.

The light stabilizers a) to d) and, if provided, are preferably added present, the other stabilizers a ') to x'), the manufacturer. Polyolefin added. This happens in the usual way per se known mixing methods, for example with melting Temperatures from 150 to 300 ° C. However, the components can also can be mixed "cold" without melting and that powdery or out Granulate existing mixture is only on during processing melted and homogenized.

It is understood that the stabilizer or stabilizers together or separately, all at once, in portions or continuously Nuclear, constant over time or along a gradient, can inflict. For example, you can use part of the stabilizer ren already during the polymerization of the olefin monomers and add the rest to the finished polyolefin.

As mixing devices for the implementation of the invention Processes are, for example, heated internal kneader with or without stamp, continuously working kneaders such. B. continuous internal kneader, snails kneader with axially oscillating screws, Banbury kneader, white extruders as well as roller mills, mixing mills with heated Rolls and calenders.  

Mixing is preferably carried out in a conventional extruder, where when the components are mixed or individually, for example full constantly introduced into the extruder via a funnel or also proportionately at a later point of the extruder to the melted or solid product in the extruder can be introduced NEN. For melt extrusion there are, for example, one or two shaft extruder particularly suitable. A twin screw extruder is prefers.

The mixtures obtained can, for example, be pelletized or granulated, or by generally known methods, for example wise by extrusion, injection molding, foaming with blowing agents, Thermoforming, blow molding or calendaring, processed who the.

Shaped bodies (also semi-finished products, Manufacture foils, films and foams) of all kinds, for example Pipes for drinking water and waste water, fittings for drinking and Sewage pipes, packaging and foils, in particular packaging genes for cosmetics (e.g. shampoo, creams, other water-based Cosmetic products) and packaging and films for food (e.g. fruit, vegetables, meat and other water-containing foods tel), drinking water bottles, molded bodies in the entire outdoor area such as B. garden furniture, windows and fittings, lamp housing, Automotive exterior parts. The molded articles are the subject of the invention. she are characterized by a significantly lower yellowing at 1 effect of water.

It has surprisingly been found that polyolefins, which are against sight bar and ultraviolet light are stabilized, and as Light stabilizers at least one of the compounds a) to d) as defined at the beginning, contain very much when exposed to water are well resistant to yellowing. These polyolefins are also Subject of the invention. In particular, these are stabilized Polyolefins in the presence of water are more resistant to yellowing than the stabilized polyolefins of the prior art.

Particularly resistant to yellowing when exposed to water Stabilized polyolefins contain min at least one of the previously described compounds a1), a2), a3), c1) and d1). These polyolefins are also the subject of the invention.

Another object of the invention is a method for ver reduction of yellowing against visible and ultraviolet Light stabilized polyolefins that are exposed to water are exposed, characterized in that the used  Light stabilizers are selected from those described Compounds a) to d), in particular selected from the be Compounds a1), a2), a3), c1) and d1).

Finally, the invention relates to the use of Light stabilizers selected from compounds a) to d) as described above, in particular selected from the Compounds a1), a2), a3), c1) and d1) as described above, in Polyolefins exposed to water.

Examples

The following were used as polyolefins:
PE: Low density polyethylene homopolymer (PE-LD), density 0.919 g / cm ³ , melt flow rate MFR (melt flow rate) 0.25 g / 10 min determined according to ISO 1133 at 190 ° C and 2.16 kg load. The product Lupolen® 1840 D from Basell was used.
PP: polypropylene homopolymer, melt flow rate MFR 23 g / 10 min determined according to ISO 1133 at 230 ° C and 2.16 kg load. The Novolen® 1100 RC product from Basell was used.

The following were used as light stabilizers:

a1: Cyanoacrylic acid ester of the formula

Uvinul® 3035 from BASF was used.

a2: Cyanoacrylic acid ester of the formula

The product Uvinul® 3030 from BASF was used.

a3: Cyanoacrylic acid ester of the formula

Uvinul® 3039 from BASF was used.

c1: Benzophenone of the formula

Uvinul® 3008 from BASF was used.

d1: cinnamic acid ester of the formula

Uvinul® 3088 from BASF was used.

V1: Benzotriazole of the formula

for comparison. The product Tinuvin® 234 from Ciba used.

V2: Benzotriazole of the formula

for comparison. The Tinuvin® 326 product from Ciba used.

Production of the mixes and test specimens

The polyolefin was cold premixed with the light stabilizer. The type and amount of stabilizer in the polyolefin is the table len 1 and 2. Then this mixture was mixed in one Twin-shaft extruder Bersttorf ZE 25 melted and homo genisiert. The melt temperature for polyethylene was 200 ° C and 220 ° C for polypropylene. The melt was discharged and granulated. The granules were made in an injection molding machine Aarburg 220 M at 200 ° C melt temperature and 220 ° C mold surface temperature test specimen of 60 × 45 × 2 mm.

Carrying out the measurements

The extent of the yellowing was determined on the basis of the yellowness index (yellowness Index YI). First of all test specimens, the YI determined before storage in water. After that, the sample body 100 hours at 25 ° C in daylight in fully desalinated water or stored in drinking water. The YI after storage in Water was found.

The YI was according to DIN 6167 and DIN 5033 with standard light D65 and 10 ° Normal observer determined.

A zero YI means that the specimen is pure white. Negative YI values mean that the test specimen is bluish (the more negative YI, the bluer), but from the human eye is perceived as particularly intense white. Positive YI Values mean that the test specimen is soluble (the more positive YI, the more yellow). The more negative the YI, the whiter it appears Test specimen to the viewer, the more positive the YI, the more yellow he appears to him.  

Tables 1 and 2 summarize the composition of the molding compositions and the measured values together. Obtain the concentration information the stabilized polyolefin (polyolefin + light stabilizer). Demineralized water means fully demineralized water, V meaning for comparison, nb does not mean determined.

Table 1

stabilized polyethylene

Table 2

stabilized polypropylene

The tables show for polyethylene (examples 1 V to 15 V) and Polypropylene (Examples 16 V to 29 V) consistent that the The method according to the invention provides stabilized polyolefins which when exposed to water, yellowing less than that after polyolefins stabilized in the prior art.

First, the inherent color of the polyolefins according to the invention is before water storage is significantly lower than the poly's own color State of the art olefins: at 0.25% by weight stabilizer The concentration in polyethylene is the YI before water storage (VE-Was ser) in the polymer according to the invention in the range from 0 to -3 (in games 2 to 6), in the polymer not according to the invention in the range from +3.5 to +5 (7 V and 8 V). At 0.5 wt% stabilizer concentrations Tration in polyethylene is the YI in the polymer according to the invention in the range from 0 to -3 (9 to 13) in the case of the invention Polymer in the range of +3.6 to +7 (14 V and 15 V).

At 0.25% by weight stabilizer concentration in polypropylene is the YI before water storage in the polymer according to the invention in the range from +1 to +8.5 (17 to 21), for the polymer not according to the invention in the range of +13.8 to +15 (22 V and 23 V). At 0.5% by weight stabilizer lisator concentration in polypropylene is the YI of the invention modern polymer in the range from +1 to +8 (24 to 27), when not polymer according to the invention in the range from +12 to +14 (28 V and 29 V).

The inherent color of the molding compositions according to the invention is accordingly white ßer than the inherent color of the molding compositions not according to the invention.  

Secondly, yellowing when exposed to water is not detectable or is only slightly pronounced in the polyolefins according to the invention: after 100 hours of storage in water, the YI of the molding compositions according to the invention changes

• - for polyethylene by about 1 to 3 YI units, for mei Most inventive examples even by less than 1 YI unit,
• - for polypropylene by about 0 to 2 YI units, in most cases Most inventive examples even by less than 1 YI unit.

In contrast, 100 hours of storage in demineralized water change the YI in the molding compositions not according to the invention

• - for polyethylene by about 10 YI units (Examples 8 V and 15 V) or even around 40 YI units (example 7 V and 40 V) in a positive direction, i.e. stronger yellowing,
• - for polypropylene by about 4 to 6 YI units (examples 22 V, 23 V, 28 V and 29 V) in the positive direction, i.e. stronger Yellowing.

The molding compositions according to the invention therefore yellow under action little or no water, whereas they do not Molding compositions according to the invention strongly yellow.

The superiority of the polyolefins stabilized according to the invention appears both in deionized water (deionized water) and in ionic water (drinking water), is therefore independent of the type of water.

Claims (10)

1. A process for the preparation of polyolefins which are exposed to the action of water, and which are stabilized against visible and ultraviolet light, in which light stabilizers are added to the polyolefin, characterized in that the light stabilizers are selected from the following compounds a ) to d)

• a) Cyanoacrylic acid esters of the formula I.
  With
  R ^I and R ^{II are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkenyl, C ₁ -C ₁₂ alkoxy, aryl, heteroaryl, optionally substituted,
  X ethyl, 2-ethylhexyl, pentaerythrityl, propane-1, 2,3-triyl, polyalkylene glycol residue,
  n integer from 0 to 3,
  m integer from 1 to 4,
• b) 4,4-diarylbutadienes of the formula II
  in which the diene system in the Z, Z; Z, E; E, Z or E, E configuration or a mixture thereof and in which the variables have the following meaning independently of one another:
  R ¹ and R ^{2 are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ -CYcloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₁ -C ₁₂ alkoxy, C ₁ - C ₂₀ alkoxycarbonyl, C ₁ -C ₁₂ alkylamino, C ₁ -C ₁₂ dialkylamino, aryl, heteroaryl, optionally substituted, water-solubilizing substituents, selected from the group consisting of carboxy lat, sulfonate or ammonium radicals;
  R ³ hydrogen, COOR ⁵ , COR ⁵ , CONR ⁵ R ⁶ , CN, O = S (-R ⁵ ) = O, O = S (-OR ⁵ ) = O, R ⁷ OP (-OR ⁸ ) = O, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₁₀ cycloalkylene, C ₇ -C ₁₀ bicycloalkenyl, Aryl, heteroaryl, optionally substituted;
  R ⁴ COOR ⁶ , COR ⁶ , CONR ⁵ R ⁶ , CN, O = S (-R ⁶ ) = O, O = S (-OR ⁶ ) = O, R ⁷ OP (-OR ⁵ ) = OC ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalcyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₁₀ cycloalkenyl, C ₇ -C ₁₀ bicycloalkenyl, aryl, Heteroaryl, optionally substituted;
  R ⁵ to R ^{8 are} hydrogen, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₃ -C ₁₀ cycloalkyl, C ₇ -C ₁₀ bicycloalkyl, C ₃ -C ₂₀ cycloalkenyl, C ₃ - C ₁₀ bicycloalkenyl, aryl, heteroaryl, optionally substituted;
  n 1 to 3,
  where the variables R ³ to R ^5, together with the carbon atoms to which they are attached, can together form a 5- or 6-ring, which may optionally be fused further,
• c) Benzophenones of the formula III
  With
  Y is hydrogen, COOR ^I or OH,
  Z OR ^I or
  A is hydrogen or SO ₃ H,
  wherein R ^I and R ^{II have} the meaning given in a), and
• d) cinnamic acid esters of the formula IV
  where R ^I , R ^II and n have the meaning given in a).

2. The method according to claim 1, characterized in that the Polyolefins are selected from homopolymers and copolymers of Ethylene and homopolymers and copolymers of propylene. 3. The method according to claims 1 to 2, characterized in that the light stabilizers are selected from the following compounds a1), a2), a3), c1) and d1)
4. The method according to claims 1 to 3, characterized in net that the light stabilizers in an amount of 0.05 up to 2% by weight, based on the stabilized polyolefin added. 5. Process according to Claims 1 to 4, characterized in that further stabilizers are added to the polyolefin, selected from the groups

• 1. a ') alkylated monophenols,
• 2. b ') alkylthiomethylphenols,
• 3. c ') hydroquinones and alkylated hydroquinones,
• 4. d ') tocopherols,
• 5. e ') hydroxylated diphenyl thioethers,
• 6. f ') alkylidene bisphenols,
• 7. g ') O-, N- and S-benzyl compounds,
• 8. h ') aromatic hydroxybenzyl compounds,
• 9. i ') triazine compounds,
• 10. j ') benzylphosphonates,
• 11. k ') acylaminophenols,
• 12. l ') esters of β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid, β- (5-tert-butyl-4-hydroxy-3-methylphenyl) propionic acid , β- (3,5-dicyclohexyl-4-hydroxyphenyl) propionic acid and 3,5-di-tert-butyl-4-hydroxyphenyl acetic acid,
• 13. m ') amides of β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid,
• 14. n ') ascorbic acid and its derivatives,
• 15. o ') antioxidants based on amine compounds,
• 16. p ') phosphites and phosphonites,
• 17. q ') 2- (2'-hydroxyphenyl) benzotriazoles,
• 18. r ') sulfur-containing peroxide scavenger or sulfur-containing anti-oxidants
• 19. s') 2-hydroxybenzophenones,
• 20. t ') esters of unsubstituted and substituted benzoic acid,
• 21. u ') acrylates,
• 22. v ') sterically hindered amines,
• 23. w ') oxamides and
• 24. x ') 2- (2-hydroxyphenyl) -1,3,5-triazines.

6. Process for reducing yellowing of visible res and ultraviolet light stabilized polyolefins that are exposed to the effects of water records that the light stabilizers used are selected are from compounds a) to d) as defined in An saying 1. 7. The method according to claim 6, characterized in that the light stabilizers used are selected from the Compounds a1), a2), a3), c1) and d1) as defined in An saying 3. 8. When exposed to water, yellowing resistant, against sight strong and ultraviolet light stabilized polyolefins, he available after the procedure according to claims 1 to 5. 9. Moldings, foils and foams made from the polyolefins according to An saying 8. 10. Use of light stabilizers selected from the Compounds a) to d) as defined in claim 1, in poly olefins exposed to water.