WO2011147835A1

WO2011147835A1 - Film arrangement with increased temperature resistance

Info

Publication number: WO2011147835A1
Application number: PCT/EP2011/058483
Authority: WO
Inventors: Kurt Stark; Karl Mauser
Original assignee: Huhtamaki Forchheim Zweigniederlassung Der Huhtamaki Deutschland Gmbh & Co. Kg
Priority date: 2010-05-25
Filing date: 2011-05-24
Publication date: 2011-12-01
Also published as: DE102010021453A1; EP2576210A1

Abstract

An embodiment of the invention relates to a film arrangement (1) with a temperature resistance of up to at least 70 °C, comprising - at least one biologically degradable base layer (5), which comprises a polyhydroxycarboxylic acid or starch, with a proportion of at least 50 wt.% of the film arrangement, said base layer having a temperature resistance of no more than 60 °C, and - at least one first temperature-resistant film layer (10) that comprises a polymer that is different from the base layer, said temperature-resistant film layer having a glass transition temperature of at least 70 °C, and/or a crystallization degree of at least 10% and a melting point of at least 70 °C. Such a film arrangement has an increased temperature resistance with respect to the biologically degradable base layer (5) but still has a sufficient degree of biological degradability and compostability as a result of the base layer.

Description

description

Foil assembly with increased temperature resistance

Films made of biodegradable, thermoplastic

Plastics such as polylactic acid (PLA) or starch are enjoying increasing popularity in the packaging of many packaged goods, such as food. These plastics are compostable one hand, but on the other hand have many advantages of conventional thermoelectric ^¬ plastics based on polyolefins.

However, a disadvantage of many biodegradable plastics based on polylactide (PLA) or thermoplastic starch (TBS) is their low temperature resistance. For example, polylactide PLA has a glass transition _Tg of about 60 ° C and therefore tends to deform at temperatures above 60 ° C. The same applies to

thermoplastic starch. To be able to process this material, plasticizers are added, the

Glass transition steps T _g between 30 and 60 ° C lead. For this reason, sheet materials or packaging materials based on PLA or starch above these temperatures are difficult to use. In particular, it can not be ensured that such packaged articles arrive undamaged at the end customer during transport through hot climatic zones of the earth.

It is therefore an object of embodiments of the invention to provide a film assembly whose temperature resistance is increased over the conventional films based on PLA or starch. This object is achieved by a film arrangement according to claim 1. Advantageous developments of this film arrangement are the subject of further claims.

An embodiment of the invention relates to a film assembly having a temperature resistance of at least 70 ° C, comprising

at least one PLA or starch-comprising biodegradable base layer having a proportion of at least 50% by weight of the film arrangement, wherein the base layer has a temperature resistance of at most 60 ° C, and

at least one first temperature-resistant film layer, one of the polymer of the base layer

comprises different polymer, wherein the

temperature-resistant film layer

o a glass transition temperature of at least 70 ° C

has, and / or

o has a degree of crystallization of at least 10% and a melting point of at least 70 ° C.

In such a film arrangement, a base layer based on PLA or starch, which has a relatively low temperature resistance of at most 60 ° C, with a first temperature-resistant film layer in the

Foil arrangement combined, so that in sum the

Foil assembly has a temperature resistance that is above the temperature resistance of the biodegradable base layer. Due to the high proportion by weight of the biodegradable base layer of at least 50% by weight, however, there is still sufficient compostability and biodegradability of the entire film arrangement

guaranteed. Moreover, the used compostable or biodegradable materials mostly based on renewable raw materials, so that these materials can be described as environmentally friendly and sustainable.

The first temperature-resistant film layer in this case has a glass transition temperature of at least 70 ° C and thus has a temperature resistance that is higher than that of the biodegradable base layer. The glass transition temperature, also known as T _g, is the temperature at which amorphous or partially crystalline polymers from a liquid or rubbery state in the hard-elastic or glassy state

go over or vice versa.

The measurement of the glass transition temperature can be carried out by various methods, such as differential scanning calorimetry (DSC). The dynamic differential calorimetry is a thermal method for determining the emitted or absorbed heat quantity of a sample during defined measurement conditions. Such a measuring method is known to the person skilled in the art and is described, for example, in the German industrial standards DIN 53765, DIN 51007 and ASTM E474 or ASTM D3418.

Alternatively or additionally, the degree of crystallinity of the first temperature-dependent film layer comprising a polymer different from the polymer of the base layer should be at least 10% and the melting point at least 70 ° C.

The degree of crystallization of a polymer indicates the proportion of molecular chains in the polymer which are present in crystalline form in contrast to the amorphous form. The degree of crystallization of a polymer also decisively determines the thermal and mechanical properties of a polymer, and with increasing degree of crystallization and the

thermal resistance of a plastic increases. Of the

The degree of crystallinity of a polymer is determined, for example, by dynamic differential calorimetry, as in

Ehrenstein, W .; Riedel, G .; Trawiel, P .: Practice of

Thermal analysis of plastics, Munich [a.a.]:

Hanser, 2nd edition 2003, described.

A temperature resistance at a certain temperature in the sense of the present inventive film arrangement is given when a sample of the film assembly of the dimensions of 100 mm in length and 20 mm in width with a residence time of 5 min at the corresponding temperature and at a load of half a kilogram Weight during this period shows a deformation of less than 10% in relation to the initial length. A test arrangement for determining the temperature resistance will be described in more detail below in the embodiments.

For the purposes of the invention, "biodegradable films" means films which are prepared in accordance with the process described in the German industrial standard DIN EN 13432

completely biodegradable. A method is used to test the aerobic compostability, which is identical to the ISO 14855: 1999 method. The test duration may not exceed a maximum duration of six months. The film arrangement to be tested must have a degree of degradation of at least 90% or 90% of the maximum value of one in the plateau phase

reach suitable reference substrate. Furthermore, a

Disintegration test carried out in the context of aerobic composting. This may after a composting of for a maximum of 12 weeks in a> 2 mm sieve fraction not more than 10% of the original dry weight of the

Test material can be found.

Preferred is polylactide, which uses polylactic acid as a polymer in the base layer. Monomers of the polylactide may be D or L-hydroxycarboxylic acids. The preparation of the polylactic acid takes place via catalytic ring opening ^¬ polymerizations of lactide, an annular

Condensation product of two lactic acid molecules, the 1,4-dioxane-3, 6-dimethyl-2, 5-dione. The preparation of polylactic acid or polylactide is also described, for example, in US Pat. Nos. 5,208,297 or 5,357,035, to which reference is hereby incorporated by reference. It is also possible to use co-polymers of lactic acid which have different monomer units. Polylactides are easy

to be produced, biodegradable polyhydroxycarboxylic acids, which are also food-compatible. The monomers

Lactic acid molecules come from renewable sources and can be produced by microorganisms via enzymatic or

biochemical processes are obtained for example from corn, potatoes or sugar beet. Manufacturer of polylactic acid or PLA is z. B. the company Nature Works®.

It is also possible to use so-called thermoplastic

Starch, for example, from natural strength through

Addition of plasticizers such as sorbitol and / or glycerol and can be prepared by homogenization in extruders. The addition of plasticizers increases the extrudability of the starch and reduces its brittleness, but also lowers the glass transition temperature of the thermoplastic starch and thus reduces its temperature resistance. The Her ^¬ position and properties of thermoplastic starch are described, for example, in the publications EP 0 397 819 B1, WO 91/16375 A1, EP 0 537 657 B1 and EP 0 702 698 B1

described.

According to a further embodiment of a film arrangement according to the invention, at least one first adhesion promoter layer is present between the base layer and the temperature-resistant layer

Foil layer available.

It is also possible that the biodegradable

Base layer and the first temperature-resistant film layer have such different chemical properties that the adhesive strengths of the two layers are often unsatisfactory. For sufficient adhesive strengths, a first adhesion promoter layer is then present, which is between the base layer and the temperature-resistant

Film layer is present and requires good adhesion of the first temperature-resistant film layer on the biodegradable base layer.

The optional adhesive layer may further comprise a plastic which is grafted with anhydride groups ^¬, such as polypropylene, ethylene vinyl acetate or ethylene acrylate, each with

Maleic anhydride are grafted. Layers ^¬ such coupling agents are particularly capable of high composite ^¬ liability of at least 5 to 10 N terephthalate per 15 mm between the different materials of the base layer, such as PLA, and between the first heat-resistant film layer, for example, amorphous polyethylene, PP or PA to enable. The adhesive layer can, depending on their glass transition temperature ^¬ and / or their degree of crystallization and the Melting point also for improving the temperature resistance of Folienanordungen invention

contribute. In a preferred variant of the invention, the adhesion promoter layer is also biodegradable and more preferably additionally made of renewable raw materials.

In a further embodiment of the invention

Foil arrangement, the base layer is amorphous or the base layer comprises an amorphous PLA or

thermoplastic starch-comprising polymer. Amorphous in the sense of the present invention are understood to mean polymers or film layers which have a

Have degree of crystallization of less than 10%.

In particular, PLA is amorphous under standard processing conditions, for example in an extrusion, by a casting or blowing process, since the process steps for producing films are so fast that the rapid

Cooling of the polymer melt in the course of film production, the crystallization of PLA practically can not take place. Also thermoplastic starch is usually amorphous.

Due to the amorphicity of these base layers have a particularly low temperature resistance. Thus, according to another embodiment of the invention, it is possible to produce conventional biodegradable base layers particularly easily by means of these standard production methods and to increase these base layers despite their lower temperature stability in film arrangements

Integrate temperature resistances.

Furthermore, it is possible for the base layer to be free from the temperature resistance-increasing additives. These additives may be polymeric modifiers, for example Example based on ethylene copolymers containing the

Temperature resistance of biodegradable polymers such as PLA can increase. Often, nucleating agents are used to effect crystallization and thereby increase the degree of crystallinity. An encore

However, such additives is usually very expensive and can also lead to a clouding or reduction in transparency. In various embodiments of the film assembly according to the invention, it is not necessary to use such additives as a sufficient, increased

Temperature stability is already ensured by the first temperature ^¬ resistant film layer.

In a further embodiment of a film arrangement according to the invention, the base layer contains exclusively PLA or copolymers based solely on PLA. Numerous examples are known from the prior art, in which by mixing other plastics,

For example, copolymers based on styrene and maleic anhydride increased temperature resistance can be achieved. Such plastic-based In ^¬ mixtures are with inventive film arrangements not necessary since, as already mentioned above, the increased

Temperature stability is caused by the first temperature-resistant film layer.

In the biodegradable base layer, plasticizers may also be present in a further embodiment of the film arrangement according to the invention. This improves the mechanical properties of the film, such as an increase in the elongation at break or higher tear and tear propagation resistance. Although the addition of plasticizers the

Temperature resistance of the base layer would lower by the introduction according to the invention of at least one temperature-stable film layer, this effect

overcompensated, so that overall results in a thermally stable film assembly, which remains thermally stable at least up to 70 ° C (and higher).

Furthermore, the base layer in a preferred

Embodiment of the invention exclusively PLA as

Polyhydroxycarboxylic comprising plastic.

It is also possible that, apart from PLA, no further plastics or polymers are present in the base layer. The monomers of the PLA base layer may comprise D-lactic acid or else L-lactic acid. The PLA base films of film arrangements according to the invention can have no or only a very small proportion of, for example, less than 10% by weight or preferably less than 5% by weight of so-called stereocomplexes of D-PLA, composed of D-lactic acids and of L-PLA, synthesized from L Having lactic acid monomers.

Such stereo complexes between D-PLA and L-PLA have partly improved material properties, but are very expensive to produce. Increase the stereo complexes of D-PLA and L-PLA often the melting point and the crystalline ^¬ sationsgrad of PLA films, which in turn results in an increased temperature stability. The stereo complexes can be produced for example by tempering of D-PLA and L-PLA-containing films, but this is time-consuming and cost-intensive ^¬. In the case of the film arrangements according to the invention, however, an increased temperature resistance is attributable to the first temperature-resistant film layer, so that pretreated PLA base films with stereocomplexes of this type need not be used to increase the temperature stability.

Preference is given to the base layer PLA, for example PLA 2002D from Nature Works®, or starch, for example Mater-BI® CF51B, Mater-BI® NF803A, Mater-BI® NF10A, or Mater-BI® CF99A from Novamont ,

In a further embodiment of a film arrangement according to the invention, the polymer of the temperature-resistant film layer is selected from a group consisting of:

Polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polyamide (PA), polystyrene (PS), polymethylmethacrylate (PMMA) and polycarbonate (PC) or any mixtures and copolymers thereof.

Such plastics, which are produced in part on the basis of crude oil, have excellent temperature stability ^¬ litäten, and are therefore particularly well suited to the

Increase the temperature stability of biodegradable base films.

Polyethylene terephthalate can be used for example in the form of so-called amorphous polyethylene terephthalate (A-PET) or as so-called glycol-based PET (G-PET or PET-G). It is also possible to use crystalline modifications of polyethylene terephthalate (such as C-PET).

Polyethylene terephthalate usually has

Glass transition temperatures of about 80 ° C and in the case of crystalline variants, a degree of crystallization between 30 and 40%. Polypropylene has a glass transition temperature of 0 to -10 ° C and is therefore used under standard conditions at 25 ° C in the rubber-elastic range. syndiotactic Polypropylene can have a degree of crystallization of 30 to 40% and isotactic polypropylene a

Crystallization degree of 70 to 80%, resulting in very high temperature resistance. For polyamides, the glass transition temperature 60 to 75 ° C and the

Depending on the structure and after treatment of the polyamide degree of crystallization between 34 to 45%. For polystyrene, depending on the processing conditions, the glass transition temperature may be about 100 ° C, with polystyrene also being amorphous

may be present. Polystyrene can also be used as a

partially crystalline thermoplastic present. Polyethylene in the case of soft polyethylene PE-LD has a glass transition temperature of -100 ° C and a degree of crystallization of about 40 to 50% and in the case of hard polyethylene PE-HD one

Glass transition temperature of -70 ° C and a degree of crystallization of about 60 to 80%.

Particularly preferred as one of the polymer of

Base layer different polymer in the first

temperature-resistant film layer amorphous polyethylene terephthalate used. Amorphous polyethylene terephthalate is also capable of forming in particularly thin layers, the

are much thinner than the base layer to cause an increased temperature resistance of the film assembly. A-PET can be processed very easily in extruders.

In such a Folienanordung is preferably a

Base layer used, which includes PLA, where PLA may be the only polymer component.

In a further embodiment of the invention, the temperature-resistant film layer may also comprise polyhydroxycarboxylic acids other than PLA. In particular, the Polyhydroxycarboxylic acid of the base layer may be selected from a group consisting of: poly-3-hydroxybutyrate, poly-3-hydroxyvalerate and poly-4-hydroxybutyrate, polyglycolic acid and any mixtures or copolymers thereof.

Poly-3-hydroxybutyrate has indeed only a glass transition temperature of 15 ° C ^¬ has a high crystallization ^¬ degree of over 60% and a melting point of over 170 ° C. Also polyglycolic acid has a relatively low glass transition ^¬ temperature of 35 to 40 ° C, but has a high

Degree of crystallization of 45 to 55% and a melting point of over 220 ° C. When using these polymers can also be a biodegradable temperature-resistant

Foil layer can be realized, so that the degree of

Biodegradability of the entire Folienanordung

can be significantly increased.

Furthermore, it is preferred if the thickness of the base layer is greater than the thickness of the temperature-resistant

Film layer. Even more preferred is the thickness of the

Base layer greater than the sum of the thicknesses of the

temperature-resistant film layer and the adhesion promoter layer. In these cases, then the biodegradable and compostable properties of the base layer are decisive for the entire film arrangement, but still due to the existing first temperature-resistant film layer increased temperature resistance of

Foil arrangement results.

More preferably, the biodegradable base layer constitutes at least 60, 70 or even 80% by weight of the film assembly, with the result that the film assembly is predominantly based on biodegradable polymers. Furthermore, it is preferred if the film arrangement

is transparent. A transparent film arrangement in the sense of the present invention is understood to mean a film arrangement which has transmission values of at least 50%, preferably greater than 80%, most preferably greater than 90%.

having. The haze is preferably less than 50%, preferably less than 25%, and most preferably less than 10%.

In a further embodiment, a film arrangement according to the invention has a temperature resistance of at least 75 °. A further increase in the temperature resistance of the film assembly above 70 ° C addition can be achieved that on the one hand, a polymer in the first

temperature-resistant film layer is used, which has a temperature resistance of at least 80 ° C or that the thicknesses of the first temperature-resistant film layer is increased compared to the thickness of the base layer. The temperature stability of embodiments of the invention Folienanordung takes in the following series

Depending on the particular plastic of the first temperature-stable film layer:

A-PET <PP <PA.

A preferred embodiment of an inventive

Foil arrangement additionally comprises:

- A second temperature-resistant film layer and

optionally a second adhesion promoter layer, wherein

the second adhesion promoter layer between the

Base layer and the second temperature resistant

Foil layer is arranged. In the case of such a film arrangement according to the invention, the base layer is thus arranged between two temperature-resistant film layers, the first and second temperature-resistant film layer, to improve the ^adhesion between the base layer and the respective temperature-resistant film layers, first and second

Adhesive layers can be present. In such a film arrangement, the temperature-resistant film layers act particularly well as a kind of "heat shields" and therefore require a particularly good increase in the temperature stability of the entire film arrangement over the temperature stability of the base layer alone.

It is also advantageous if the thickness of the base ^¬ layer is greater than the sum of the thicknesses of the first and second temperature-resistant film layers and the

optionally present first and second adhesion promoter layers, so that again the compostability and biodegradability of the entire film assembly is determined primarily by the base layer.

According to a further embodiment of the film arrangement according to the invention, this may comprise, in addition to the base layer and the temperature-resistant film layer, a further, second base layer, wherein the temperature-resistant

Foil layer between the base layer and the further, second base layer is arranged.

In such a film arrangement, the temperature resistance is also increased in comparison to film ^¬ layers, which are made only of PLA or starch, due to the particularly high proportion of the base layers, the biodegradability is particularly high. Such a film arrangement may further comprise a second adhesion promoter layer which is arranged between the temperature-resistant film layer and the further, second base layer in order to ensure better adhesion between the temperature-resistant film layer and the further, second base layer.

The at least two base layers preferably comprise PLA. Furthermore, in the film arrangement, the temperature-resistant film layer may be on both sides of at least two

Be surrounded by base layers. In such a Folienanordung also results in an increased temperature ^¬ resistance with a particularly high proportion of biodegradable materials.

Due to the good compatibility between the base ^¬ layers, base layers, which are present on the same side of the temperature-resistant film layer can be arranged directly above each other without

Adhesive layers are arranged therebetween.

In particular, the outer layers of more

Embodiments of film assemblies of the invention may contain additives such as antiblock and slip additives which have a significant influence on the coefficient of friction of the film assembly against itself or against other substrates such as steel or glass. A possible slip-antiblock combination is Sukano® PLA DCS 511. The film arrangement can be further refined and, for example, provided with an imprint, or stretched, embossed, siliconized and / or laminated. Furthermore, it is possible that the film assembly by coextrusion, for example by means of the cast or

Blowing process can be produced. This can be produced in a particularly simple manner film assemblies containing the base layer, the adhesive layer and one or more temperature-resistant ^¬ film layers. By means of this simple production process, base layers based on

Polyhydroxycarboxylic acids, such as PLA, are produced, these layers have a high amorphicity

have and therefore a low temperature stability

have, but by the temperature-stable

Film layers are stabilized.

In the following, variants of the film arrangement according to the invention will be explained in more detail with reference to figures and exemplary embodiments. Show it:

1 shows a cross section through an embodiment of a film arrangement according to the invention,

2 shows a cross section through a further embodiment of a fiction, modern ^¬ film arrangement with two thermally resistant film layers,

Figure 3 is a schematic drawing of an experimental arrangement for determining the temperature resistance.

1 shows in cross section a film assembly 1 with a biodegradable base layer 5 to which a first ^{temperature-¬} resistant film layer 10 was applied by means of a first adhesive layer 15 °. As discussed above, the biodegradable Base layer, for example, from conventional, in no way modified to increased temperature stability

Polylactide PLA, for example the polylactide PLA 2002D from Nature Works®. On this base layer is a first

Adhesive layer 15 applied, for example

Ethylene acrylate grafted with maleic anhydride groups, such as the Bynel 21E830 coupling agent from Dupont®. On the first primer layer, the first temperature-resistant film layer is applied, for example, amorphous polyethylene terephthalate ^¬ .

Figure 2 shows another embodiment of a film assembly fiction, modern ^¬, wherein in addition to the arrangement shown in Figure 1 film a second adhesive layer 16 and a second heat-resistant film layer 11 are present. In such a film arrangement, the PLA base layer 5 is particularly well protected against elevated temperatures.

The layer thickness of the base layer may be, for example, 10 μm to 2,000 μm, preferably 15 mm to 1,500 μm, most

preferably 20 ym to 1000 ym amount.

The layer thickness (s) of the temperature-resistant

The film layer (s) and optionally the adhesion promoter layer (s) may be, for example, 2 μm to 2,000 μm, preferably 5 μm to 500 μm, most preferably 10 μm to 100 μm.

In particular, the layer thickness 210 ym for the

Base layer, 40 ym for the first and second ^{adhesive ¬} mediator layer and each 30 ym for the first and second temperature-resistant film layer amount. FIG. 3 shows a schematic arrangement for determining the temperature resistance. In this case, a film assembly 1 between two metal plates 20, which were fastened together by means of screws 30, clamped and fixed by means of a rod 35. The sample of the film assembly 1 had a length of 100 mm and a width of 20 mm and consisted of different film assemblies according to the invention, or

conventional film assemblies as Comparative Examples. To this film assembly was a weight 25 of 0.5 kg

attached and the samples were at different temperatures under the weight load for 5 min each. exposed so that a train in the direction of the arrow designated 40 occurred. As temperature stable, a sample was then seen ^¬ when they at a certain temperature below

Weight load had a change of less than 10% compared to the original length.

Tables 1 to 5 show the structure and composition of the various film layers of five different embodiments of the invention

Foil arrangements, while Tables 6 and 7 the

Comparative Examples 1 and 2 without the temperature-resistant film layers show.

Table 1: Embodiment 1 (co-extruded cast film) with PLA base layer and two temperature-stable

Foil layers of A-PET Layer composition Share in thickness in

Number layer ym

in% by weight

1 • NOVAPET CR, APET • 99 30

• Antiblock with • 1

silica

2 • bonding agent • 100 40

Bynel 21 E 830

3 • PLA 2002 D • 100 210

4 • bonding agent • 100 40

Bynel 21 E 830

5 • NOVAPET CR, APET • 99 30

• Antiblock with • 1

silica

Example 2 (coextruded Castfol with PLA base layer and two temperature-stable

Film layers made of PP

Table 3: Embodiment 3 (coextruded cast film) with PLA base layer flanked by two temperature-stable film layers made of PA Layer composition Share in thickness in

Number layer in ym

wt%

1 • polyamide • 100 30

Ultramid B36 LN

2 • bonding agent • 100 40

Bynel 21 E 830

3 • PLA 2002 D • 100 210

4 • bonding agent • 100 40

Bynel 21 E 830

5 • polyamide • 100 30

Ultramid B36 LN

Table 4: Embodiment 4 (coextruded cast film) with four PLA base layers flanking a temperature-stable film layer of PP

Layer composition Share in thickness in number layer in ym

wt%

1 • PLA 2002 D • 98, 2 49

• Sukano PLA DC S 511 • 1.8

Slip Antiblock Combi + Clarifier

2 • PLA 2002 D • 100 75.5

3 • bonding agent • 100 21

Bynel 21 E 830

4 • Polypropylene PP • 100 59

Bormed HF840MO

5 • bonding agent • 100 21

Bynel 21 E 830

6 • PLA 2002 D • 100 75.5

7 • PLA 2002 D • 98, 2 49

• Sukano PLA DC S 511 • 1.8

Slip Antiblock Combi + Clarifier Table 5: Embodiment 5 (coextruded cast film) with a PLA base layer flanked by two temperature-stable G-PET film layers

Table 6: Comparative Example 1: PLA layer arrangement

(co-extruded cast film) with PEG 35000 as plasticizer temperature-stable film layers

Layer composition Share in thickness in number layer in ym

wt%

1 • PLA 2002 D • 98 42

• Sukano PLA DC S 511 • 2

Slip Antiblock Combi + Clarifier

2 • PLA 2002 D • 45 45.5

• Compound PLA • 55 (85%) + PEG 35000S

(15%)

3 • PLA 2002 D • 25 175

• Compound PLA • 75

(85%) + PEG 35000S

(15%)

4 • PLA 2002 D • 45 45.5

• Compound PLA • 55

(85%) + PEG 35000S

(15%)

5 • PLA 2002 D • 98 42

• Sukano PLA DC S 511 • 2

Slip Antiblock Combi + Clarifier

Table 7: Comparative Example 2: PLA layer arrangement (co-extruded cast film) without temperature-stable

film layers

Layer Composition Share in thickness

Number layer in in ym

1 • PLA 2002 D • 98 42

• Sukano PLA DC S 511 • 2

Slip Antiblock Combi + Clarifier

2 • PLA 2002 D • 100 49

3 • PLA 2002 D • 100 168

4 • PLA 2002 D • 100 49

5 • PLA 2002 D • 98 42

• Sukano PLA DC S 511 • 2

Slip Antiblock Combi + Clarifier The following Table 8 shows the expansion behavior of the embodiments 1 to 5 and Comparative Examples 1 and 2 and thus their temperature stability in comparison.

Example of embodiment / temperature in ° C. Length change in comparative example mm (relative to 100 mm long film strip with width

20 mm)

Embodiment 1 50 0

53 0

60 0

64 2

68 3

72 5

74 9

76 23

Embodiment 2 50 0

53 0

60 0

64 2

68 4

72 4

6

76 6

78 6

80 8

Embodiment 3 50 0

53 0

60 0

64 0

68 0

72 1

74 1 Example of embodiment / temperature in ° C. Length change in comparative example mm (relative to 100 mm long film strip with width

20 mm)

2

80 2

Embodiment 4 50 0

53 0

60 0

64 2

68 4

72 5

74 7

76 7

78 9

80 10

Embodiment 5 50 0

53 0

60 0

64 2

68 4

72 9

74 11

76 27

Comparative Example 1 50 0

53 2

60 12

64 32

68 38 Example of embodiment / temperature in ° C. Length change in comparative example mm (relative to 100 mm long film strip with width

20 mm)

Comparative Example 2 50 0

53 0

60 7

64 22

In the embodiments 1 to 5 according to the invention are temperature stabilities of about 74 ° C to 75 ° C.

(Embodiment 1), Above 80 ° C (Embodiments 2 and 3), 80 ° C (Embodiment 4) and up to 73 ° C.

(Embodiment 5) before. Here are the foil ^¬ arrangements, in which a PLA base layer of two

flanked by temperature-stable film layers,

more stable in temperature than the foil arrangement, in which a temperature-stable foil layer is surrounded by outer PLA base layers. All embodiments according to the invention have greatly increased temperature stabilities relative to Comparative Examples 1 (below 60 ° C.) and 2 (approximately 60 to 61 ° C.). The film arrangements with PP and PA as temperature-stable film layers have higher temperature stabilities than the film arrangement with A-PET as a temperature-stable film layer.

Claims

claims

1. Folienanordung (1) with a temperature resistance to at least 70 ° C, comprising

at least one polylactide or starch-comprising biodegradable base layer (5) having a proportion of at least 50% by weight of the film arrangement, wherein the base layer has a temperature resistance of at most 60 ° C, and

at least one first temperature-resistant film layer (10) comprising a different from the base layer polymer, wherein the temperature-resistant

film layer

o has a glass transition temperature of at least 70 ° C, and / or

2. Film arrangement according to the preceding claim,

- wherein the base layer is amorphous with a glass transition ^¬ temperature of at most 60 ° C.

3. Film arrangement according to one of the preceding

Claims,

- wherein the polymer of the temperature-resistant film layer is selected from a group consisting of: polyethylene, polyethylene terephthalate, polypropylene, polyamide, polystyrene and polycarbonate or any mixtures thereof.

4. foil arrangement according to one of the preceding claims,

- wherein the polymer of the temperature-resistant film layer is selected from a polyhydroxycarboxylic acid except PLA.

5. Folienanordung according to the preceding claim,

wherein the polymer of the temperature-resistant film layer is selected from a group consisting of: poly-3-hydroxybutyrate, poly-3-hydroxyvalerate,

Polyglycolic acid and poly-4-hydroxybutyrate and any mixtures and co-polymers.

6. foil arrangement according to one of the preceding claims,

- wherein the Folienanordung is transparent.

7. Film arrangement according to one of the preceding

Claims, wherein

at least a first adhesion promoter layer (15) between the base layer (5) and the temperature-resistant

Foil layer (10) is present.

8. Folienanordung according to any one of the preceding claims,

- The adhesive layer is a plastic

which is grafted with acid anhydride groups.

9. Folienanordung according to any one of the preceding claims,

- wherein the thickness of the base layer is greater than that

Thickness of the temperature-resistant film layer.

10. Folienanordung after one of the preceding

Claims,

- Wherein the base layer is free of the temperature ^¬ resistance-increasing additives.

11. Foil arrangement according to one of the preceding

Claims,

- The base layer contains only PLA as a polymer.

12. Film arrangement according to one of the preceding

Claims additionally comprising:

- A second temperature-resistant film layer and a second adhesive layer, wherein

the second adhesion promoter layer between the

Base layer and the second temperature-resistant film layer is arranged.

13. Foil arrangement according to one of the preceding

Claims,

- The film arrangement can be produced by co-extrusion.

14. Folienanordung according to one of the claims 1 to 11 and 13, additionally comprising:

- Another, second base layer, wherein

the temperature resistant foil layer between the

Base layer and the further, second base layer is arranged.

15. Folienanordung according to the preceding claim, additionally comprising

a second primer layer interposed between the

temperature-resistant film layer and the further, second base layer is arranged.

16. A foil assembly according to any one of claims 14 or 15, wherein the base layers comprise PLA.

17. Film arrangement according to one of the claims 14 to 16, wherein the temperature-resistant film layer is surrounded on both sides by at least two base layers.

18. Folienanordung according to the preceding claim, wherein the base layers are arranged directly above one another on the same side of the temperature-resistant film layer.

19. Film arrangement according to one of claims 14 to 18 in which a temperature-stable film layer is surrounded by outer PLA base layers.

20. Film arrangement according to one of claims 1 to 13, wherein the base layer includes PLA and the

temperature stable film layer amorphous

Polyethylene terephthalate.