CA1304529C

CA1304529C - Compatible polymer blends useful as melt adhesives

Info

Publication number: CA1304529C
Application number: CA000577732A
Authority: CA
Inventors: Pallavoor R. Lakshmanan; Paula J. Carrier
Original assignee: Baychem International Inc
Current assignee: Baychem International Inc
Priority date: 1987-12-11
Filing date: 1988-09-16
Publication date: 1992-06-30
Anticipated expiration: 2009-06-30
Also published as: US4761450A

Abstract

ABSTRACT
Compatible polymer blends useful as molt adhesives comprising a low density ethylene polymer, a copolymer of butene-1 and ethylene or propylene, a hydrocarbon tackifier and a low molecular weight polymer selected from the group consisting of a low molecular weight liquid polybutono, an amorphous polypropylene and mixtures thereof.

Description

~OMPATIBLE POLYMER ~LENDS USEFUL AS MELT ADHESIVES

1. ~b~
Thl~ Inventlon relates to compatlble polymor blends useful as melt adheslves comprlsln~ (l) a low donslty ethylene polymer, (2) a copolymor of butene-1 and ethylono or propylene, (3) a hydrocarbon tacklfler and (4) a low molecular welght polymer selected from t~e group conslstlng of (a) a low molecular welght llquld polybutene, ~b) an amorphous (atactlc) polypropylene and (c) mlxtures t~ereof.

2. DescrlDtlon of the Prlor_Art Hot melt adheslves have found extenslve use In Industry ln bondlng, Jolnlng or fabrlcatlon of varlous structures, Includlng constructlon of structures from synthetlc polymerlc fllms, such as polyethylene, polypropylene, etc.:
foll, Includlng metal foll, such as alumlnum; wax-coated or wax-lmpregnated celluloslc structures; and varlous non woven materlals whose constltuent~ are based on polyolefIns, polyester~, polyamldes and acryllc-type polymers.
The modern trend ln the packaglng Industry, for example, 19 to use more of the plastlc based or plastlc flnlshcd constructlon~, ~uch as polyethylene or polypropylene extruslon coated or lamlnated boards. Such ~tructures are repl~cln~ conventlonal clay coated boards ln many packaging appllcatlons. The advantages of using composlte constructlon of plastlc to plastic or plastlc to paper, and other such comblnations, are several, for ~304529 example. wlth re~p~ct to ~e~thotlc~. prlnt g~aphlc~ rrl~r propertles toward molature thumldlty), oxysen and odor, etc.
A better barrler. for example, wlll prevent or tend to lnhlblt early spollage of the packaged contents. Plastlc utlllzed composlte con~tructlons are now routlnely u~d for bevera~e cartons or sleeves, to hold dry ~oods and con~umablc Itema, frozen Julce, household detergents and cleaners, poultry and fresh produce packaglng, etc.
The change In varlous packaglng lamlnate and non woven disposal constructlon structures from paper or paperboard to plastlc and non-woven based products also necessltates that the varlous adheslves choYen to hold the structures together be compatlble wlth the materlals of constructlon, slnce the altered surface chemistry of such materlals may not be adheslon compatlble with tradltlonally avallable hot melt adhes 1 ves .
Thus, lt 19 Important that the hot melt adheslve~ used to prepare the varlous composltes be compatlble with the materlals of constructlon and that they exhiblt good speclflc adheslon thereto, partlcularly whereln such materlals are made uslng synthetlc polymers, such as polyethylene, polypropylene, etc.
In addltlon, slnce hot melt adheslves are a multlcomponent system whlch experlences prolonged elevated temperature exposures, for example at 350F, or even hlgher, ln productlon or use, lt is especially lmportant that they ~04SZ9 s~ow melt stablllty ovor a porlod of tlmo untll tholr u~e and not lo~e thelr homo~onolty, bocomo un~tablo and show ~tratlflcatlon, rosultln~ In a substantlal 109~ In thelr adhe~lve performance. Moreover, some hot melt adheslves, even at such elevated temperature~, are stlll so vl~cous, for example, they can have a vl~co~lty at ~uch tomPerature well above 15,000 Cp9. that they can be applled to the substrate wlth only very great dlfflculty.
We have found that the novel polymer blends defIned and clalmed hereln, that Is, contalnlng a low denslty ethylene polymer; a copolymer of butene-1 and ethylene or propylene;
a hydrocarbon tacklfler; and a low molecular welght polymer selected from the group conYl~tlng of a low molecular welght llquld polybutene, an amorphous polypropylene and mlxtures thereof i9 eminently useful as a hot melt adheslve wlth the ~ubstrates deflned above, In that they are compatlble therewlth, exhlblt remarkable adheslon thereto and remaln ~table at elevated temperatures of appllcatlon.
~UMMARY OF THE INVENTION
The novel compatlble polymer blends useful as hot melt adhesives deflned and clalmed hereln comprlse (1) a low denslty ethylene polymer, C2) a copolymer of butene-1 and ethylene or propylene, C3) a hydrocarbon tacklfler and C4) a low molecular welght polymer selected from the ~roup conslstlng of Ca) a low molecular welght llquld polybutene, (b) an amorphouY polypropylene and Cc) mlxtures of low molocular wol~ht llquld polybuton~ ~nd ~morphoua polypropylono~. It la obv~ou~ wlll be ~oon ln the ~peclflc runs heroln~fter, that tho novel Polymer blend~ can Include thereln more than one of each of the above components.
The low denslty ethylene polymers u~ed hereln can de~lrably be obtalned from conventlonal fllm formln~ a3 well as other speclalty grades of ethylene polymers havlng a denslty of about 0.88 to about 0.94, preferably about 0.88 to about 0.93 and a melt Index, as determlned by ASTM-1238, In the range of about 3 to about 5000 gr~mY/10 mlnutes, or above, Includlng those whlch extend Into low vlscoslty values, l.e., about 40 cps at 140C., preferably from about 20 to about 500 grams/10 mlnutes, These low denslty ethylene polymers can be prepared by well known hlgh pressure proce~ses, or by lower pressure processes, by copolymerizing ethylene wlth C3 and hlgher alphaoleflns. Deflnltlons of low denslty polyethylenes can be found, for example, ln U.S.
Patent Nos. 4,076,670 to Godfrey, 4,120,916 to Meyer, Jr., ct al, 4,373,066 to Karlm et al and 4,471,086 to Foster.
The copolymer of butene-1 and ethylene or propylene used herein are hlgh molecular welght polymer~, generally rlgld at atmospherlc temperatures but easlly flowable when heated. Thelr melt Index, determined In accordance with ASTM D1236 1~ deslrably In the range of about 0.3 to about -` i304S29 ~000 gram~/10 mlnut~a, and ~ven hloh~, prefor~bly In tho ran~e of about 3.0 to about 2000 ~ruma~0 mlnuto~, at 350F.
Slnce ethylene, and oven propylene, can be proaent durln~
the polymerlzatlon process whcn butene-1 Is polymcrlzed to prepare the butene-1 copolymor that can bo u~od horoln, tho resultlng comonomera wlll contaln from about 1.5 to about 20, generally from about 3.0 to about 10, wel~ht percent of ethylene or propylene. DeflnltlonY of sultable butene-1 copolymers can be found, for example,, In U.S. Patents Nos.

3,573,240 to Flanagan and 4,568,713 to Hansen.
The hydrocarbon tacklflers sultable for use hereln can be selected from any hydrocarbon tacklfler generally used, or sultable for use, ln the preparatlon of hot melt adheslves. A particularly sultable tacklfler can be obtained from commercially avallable hydrocarbon reYinY
resulting from the polymerlzatlon of monomers conslstlng of olefins, cyclooleflns and dloleflns, for example, resldual byproduct monomers resultlng from the manufacture of Isoprene. Such tacklflers are descrlbed, for example~ ln U.S. Patents Nos. 3,932,330 to Lakshmanan, 4,022, 728 to Trotter et al and 4,072,735 to Ardemagnl. Such petroleum derlved hydrocarbon reslns are sometlmes referred to also as synthetlc terpene reslns. Other types of tacklflers Included for use hereln Include conventlonal terpene resln~
and modlfled terpene reslns obtalned as a result of the polymerlzatlon of ~uch terpene derlved monomers, ~uch as _5_ i304S29 ~lPha- an~ ~t~- Pln~n~ an~ llmon~no. Potroloum h~droc~r~on reslns that have boon post hydrogonatod to ylold a more thormally otablo ~ln can al~o bo u~ed. Tho tacklflor~
used hereln to prepare the novel hot melt adheslve hereln wlll typlcally exhlblt a rlng and ball softenlng polnt ~ASTM
E 2~ ln the range of about 10 to about 150C, gonerally In the range of about 10 to about 140C.
The fourth necessary component used to prepare the novel hot melt adhe~lvcs 19 elther a low molecular welght llquld polybutene, an amorphous polypropylene or mlxtures of the two.
The low molecular welght llquld polybutenes used hereln are polymers of Isobutylene and butenes, composed predomlnately of monooleflns havlng four carbon atoms, that 19, from about 85 to about 98 welght percent, wlth the remalnder belng composed predomlnantly of lsoparafflns, havlng a molecular welght ~as determlned by a Mechrolab Osmometcr~ In the range of about 500 to about 5000, generally from about 1300 to about 3000. Such polybutenes are de~cribed, for example, In U.S. Patent No. 4,072,735 to Ardemagnl.
The amorphous polypropylenes, Includlng amorphous polyalphaolefins, used hereln to prepare the novel hot melt adheslve are soluble in hydrocarbon solvent~, such as pentane, hexane, etc., have a crystalll nlty of less than about 10 welght per cent, preferably less than about flve welght percent, and poaa~o~ a molocular wolght In the range of about 300 to ~bout 20,000, pro{orably about 1000 to ~bout 15,000. The method usod In prep~rlng the amorphous polypropylene or amorphous polyalphaoleflns, and recoverlng the same, has no effect on Its utlllzatlon In the preparatlon of the novel hot melt adhe~lve clalmed heroln, Thus, amorPhous polypropylene formed as a byproduct In mlnor amounts durlng the productlon of crystalllne polypropylene by the polymerlzatlon of propylene In the presence of stereospeclflc catalysts by processes dlsclosed, for example, In U.S. Patent No. 3,679.775 to Hagemeyer et al can be used. On the other hand, amorphous polypropylene (amorphous polyalphaoleflns) produced dlrectly, wlthout the productlon of crystalllne copolymers of propylene and lower oleflns, as dlsclosed, for example, In sald U.S. Patent No.
3,679,775 to Hagemeyer et al can also be used. While the amorphous polypropylcne~ (amorphous polyalphaoleflns) used hereln can be homopolymers of propylene, lt is wlthln the purvlew of our lnventlon to use substantlally amorphous - products based on propylene copolymerlzed wlth olefIns, such as ethylene, butene, pentene, hexene, nonene, decene, etc., whether ~uch products have been obtalned Intentlonally or as by-products. Such amorphous polyalphaolefIn copolymers can ; have a melt vlscoslty In the range of about 200 to about 50,000, or even hlgher, cps at 375F (ASTM D 3236). These copolymers wlll contaln propylene ln an amount ranglng from t -7-:, about 25 to a~out 99.5, or ovon hl~her, welght po~cent, ~enerally from about 50 to about 99.5, or ovon hlghor, welght percent, wlth the ~emalnder beln~ the one or more of the oth~er oleflns deflned above. The amorphous polyalphaoleflns useful hereln aro further descrlbod, for example, ln U.S. Patont~ No~. 3,900,694 to Jurron~, 3,92375 to Carter, Jr. et al, 3,954,697 to McConnell at al, 4,022,728 to Trotter et al, 4,120,91~ to Meyer et al.
4,210,570 to Trotter et al, 4,259,470 to Trotter et al, 4,264,756 to Trotter et al and 4,288,358 to Trotter et al.
The four components requlred to obtaln the novel hot melt adheslve hereln can be present In the amounts deflned below In Table I.
T~BLE I

Preferred Broad Ranae Ranae (1) Low Denslty Ethylene Polymer 2.5 - 40 5 - 30 ~2) Butene-1 Copolymer 5 - 60 10 - 50 (3) Hydrocarbon Tacklfler 5 - 40 10 - 35 (4) Low Molecular Welght Llquld Polybutene or 5 - 60 10 - 40 Amorphou~ Polypropylene 5 - 87.510 - 75 In addltlon to the amount~ Yhown above ln Table I the welght ratlo of low den~lty ethylene polymer to the butene-1 copolymer wlll be ln the range of about 9:1 to about 1:9, preferably In the range of about 1:3 to about 3:1. When a mlxture of low molecular welght polybutene and amorphous polypropylene l~ u~ed, the amount of amorphous polypropylene 13045~9 p~esent In auch mlxturo can bo In the rango of a~out 97.5 to about 2.5 we~ght percent, generally In the range of about 75 to about 40 welght percent, wlth the remalnder b~lng the low molecular welght llquld polybutene.
In an embodlment hereln, our novel hot melt adheslve can have Incorporated thereln a paraffln or a mlcrocrystalllne wax In order to reduce the vlscoslty thereof to facllltate the appllcatlon of the adhoslve to a substrate. ParaffIn waxes uQed are those composed malnly of stralght chaln or branched chaln molecules. Fully refIned parafflns are hard and brlttle wlth meltlng polnts ranglng from about 115 to about 155F. Mlcrocrystalline waxes that are ùseful are those that are complex mlxtures of monocycllc and polycycllc hydrocarbonY, along wlth lesser amounts of branch chalns and Isoparafflns contalnlng only mlnor amounts of normal parafflns. The crystals of mlcrocrystalllne waxes are much smaller than those of paraffln waxes. The meltlng polnts of the mlcrocrystalllne waxes wlll range from about 140 to about 190F. When a wax 19 used Jt can be present In an amount upto about 40 welght percent, based on the flnal adhe~lve composltlon, but generally the amount used wlll be le99 than about 25 welght percent.
Slnce hot melt adhe~lves tend to experlence varylng degrees of thermal exposure durlng thermal processlng and~or durlng applIcatlon to the substrate, It ls deslrable to Incorporate thereln one or more antloxldants In small :

: _9_ amounts to Inhlblt thermal and/or thermooxldatlvo degradatlon. Se~oral typoa of commorcl~l productY, predom~nantly of the hlndered phenol types, are avallablo for thls purpose to functlon as prlmary antloxldants. A
secondary antloxldent belonglng to the general cla~slflcatlon of thloesters and phosphltos can also be uscd ln comblnatlon wlth the hlndered phenols. Exemplary of antloxldants sultable for use hereln Include tetrakls ~methylene 3-~3',5'-dl-t-butyl-4-hydroxyphenyl~ proplonate]
methane; ~-2'-ethylldenebls (4,6-dl-tertlary-butylphenol);
1,1-3-trls ~2-methyl-4-hydroxy-5-t-butyl phenyl) butane; and 1,3,5-trlmethyl-2,4,6-trlQ 13,5-tert-butyl-4-hydroxybenzyl~
benzene. Secondary antloxldants, such as dllaurylthlodlproplonate; dlstearylthlodlproplonate;
pentaerythrltol tetrakls (beta-laurylthloproplonate) and varlous alkyl-, aryl-, dl- and polyphosphltes and thlophosphltes, can also be employed ln comblnatlon wlth approprlate hlndered phenols. Effectlve amounts of antloxldants that can be u~ed can range from about 0.05 to about 5 welght percent, preferably from about 0.1 to about 2.5 welght percent, based on the welght of the final adhe~lve composltlon.
The preparatlon of the novel melt adheslve clalmed herein 1~ not crltlcal and any sultable method can be employed. In a preferred embodlment, a mlxlng vessel ls heated to an elevated temperature, for example, In the range of about 325 to about 400F and the low den~lty ethylene polymer, the bu~ene-1 copolymer and tho antloxldant, lf uYed, are added thereto. The polymer mlxture 1~ allowed to ~often under 910w mlxlng and then the t~cklfler 19 ~ded and mlxlng 19 contlnued untll homogenlzatlon occu~. The low molecular welght polybutene, amorphous polyPropylene or comblnatlons thereof 19 then added In small quantltles under continued mlxlng untll homogenlty of the mlxture 19 attalned. If wax 19 alYo uYed, It 19 added at the tlme of polybutene or amorphouY polypropylene addltlon. The total mlxlng tlme Is generally In the range of about 0.5 to about two hours.
DESCRIPTION OF PREFER~IILIJ 1~
The present Inventlon can further be Illustrated by the followlng. A number of composltlons were prepared us}ng an oll heated Brabende~ mixlng ve~sel havlng a compoundSng bowl wlth a capaclty of 400 mllllllters. Before beglnnlng, the mlxlng vessel was heated to a temperature ranglng from 350 to 380F. The varlous Ingredlents were mlxed at such temperatures, starting with the low density ethylene polymer, butene-1 copolymer and one or more antioxidant~.
At thls temperature the polymers were allowed to soften under slow mlxlng, wlth the tacklfler belng added a. thls polnt. Followlng homogenlzatlon, the low molecular welght polybutene, or amorphous polypropylene, when used, was added ln small quantlties under contlnued mlxlng untll the deslred *trademark .~ ~, . ..

` i304529 homogenelty of the mlxture wa9 obtalnod. Whon wax was added, thls was done at the tlme of polybutene or amorphous polypropylene addltlon. Total mlxlng tlme ran~ed from about one to about 1 1~2 hour~. Tho mlxod compo~ltlon wa~ then collected on a release llne tray.
The thermal ~tabllltles of the adheslve composltlons that were prepared were determlned by exposlng about 8 to 10 gram quantltles of a sample In a fIve-lnch x one-lnch test tube to a temperature envlronment of 350F for 24 hours. At the end of the 24 hours, the composltlon was vlsually observed for any ~eparatlon stratiflcatlon and lo~s In composltion homogenelty. The rlng and ball softenlng polntq of the composltlons were determlned according to ASTM
Procedure E28. The melt vlscosltles of the composltlons were determlned accordlng to ASTM Procedure D 3236, whlle the needle penetratlons were determlned accordlng to ASTM D
1321.
To determlne peel 9trength values of the composltions, polyethylene lamlnated test speclmens were prepared by applylng the composltlons to a 4.0 mil (one lnch by four Inch) hlgh denslty polyethylene fllm by means of a Slautterback "mlnisqulrt~ hot melt gun. The composltion was applled at 350F to the film as a contlnuous strlp 1/2 Inch wlde acros~ the film width and then a film of the same dlmenslons was placed on top of the film carrylng the strlp of the composltlon. The lamlnates were then aged for a B *trademark mlnlmum of 24 hours prlor to testln~. Th~ee ~pcclmen~ foreach composltlon were prepared and the bond ~trength was measured by peellng at the ~lue llne by mean~ of a J. J. Lloyd~Ten~llo Te~ter at a peel rate of 50 mllllmeters per mlnute. The maxlmum force In ~rams necessary to cau~e rupture of the bond wa~ noted. The average of the three such determlnatlons was recorded.
Polypropylene and polypropylenefKraft*lamlnate test speclmens were prepared by applylng each of the composltlons ~o prepared to a 3.0 mil ( one Inch by 91X Inch) polypropylene fllm or to a 30 pound (one Inch by slx Inch) Kraft strlp by means of a Slautterback ~mlnlsqulrt~' hot melt gun. The composltlon was appl}ed at 350F to the fllm or Kraft* paper as a contlnuous 1/2 lnch strlp across the wldth (one Inch~ of the substrate. Then a fllm of the same dlmenslon was placed on top of a fllm or paper carrylng the strlp of the composltlon. The lamlnates were then aged for 24 hours prlor to testlng. Testlng procedures were the same as for the polyethylene speclmens.
The components used in the preparatlon of the polymer blends are Identlfled below In Table 11. In the tables herein the butene-1 copolymers are referred to as polybutylene.

*trademark - 13-B-~304æs uuuuuu uuu - u u u m n n n ' ~ u n n O ~D 0 V V V V V g~ V V t i~

U I N 1'~ m tn m ~o to o to m 90 t~ n~ m m ~ _ ~~ mm~Ommmmmmmmmm U I .J V V V ~ V V d d d ~ d d d ~ d d d d d t~l D ~ D tD ~ ~ c ~ ~ ~ c ~
u I c~ a c~ c~ o c~ c ~c tc cc cc tc tc cc tc cc tc tc tt ; I U ~ O n r~ ~ a U n m to r r) I 1~ ¦ o oN _ _ _ U U U ~ ~--m -- C U U
L I Z ~r ~t ~Ur ~ O C~ --~ t~ t~ 2 ~ ~ t, ~ ,,0 V, ~ U U U ~ C U U Uc C Uc ~ E o E e E
s u c o o o o ~ 2 ~ u u u u u u - m i ~ ~ ~ ~r to u~ c t~ o w w I I I m ~ m 5 C ~o I tc cc tc . G li tC St G; tC e at~tit'i I ~ u tc '~ ~ ,.O

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o I o o o o o o o ~ I V ~, V 'O ~ o 0 ~ V V V

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x j U U ~.u U o j ~o o o E I ~ OE E ~ E ~ E c I _ _ ~ I rr~rr m 1 ~-- ~ a I a <~ I IrCI

.

, ~04S29 The data ~o obtalned aro oet forth below In Table III.

' i304æ9 nn ' ~q ' ' ' ' ~ ' o 8 ~N~o n ~ ,~ 3 8 8 8 8 Q ~
~o I I ~ I I I I 0 8 ~ N N m n ¦ 8 8 ~ 8 ~ 8 . ~

8 8 8 8 ~ ~ m 8 nn ~ n ~ ~ ~ n ~ ~ o 8 ~NNn - I
n ~ ¦ n n I ~ ~ ~ n ~ ~ ~ o g ~ ~ g m I D I n 8 1 1 1 1 1 I o N ~ ~ N _ I
I N N 11~ -- n n n o o ~ I I ` I ~ O ~ m ~ n _ r ~no o o --N
- -nn .~
~
0 ~ jc o O C .~ I o ~ I ~
m ~
~ ~ ~ 3 n j o* ~ ¦ ~ ^ -U 3 ~ ~ a ~ !j e n ¦ c r O

ON ~ - æ N ~ j _ ~ ~ C ¦ ~ 2si nQ ~
n n 3 J ' O X 1~ o L i _ O ~ O ~
C J ~ 3 ~ 10 Il. ~ m ~ Z S j ~

.

l304æs 8 8 8 " ~on ~ o O I i I I I I ~ O o N ~~ ~ I ~ I
o ~ n N n o o .. ~
u . ! ~ 8 1 1 8 1 8 1 1 1 8 ~ O o ~ n ~ ~ ~
2 _ _ m o ~ ~ 8 1 1 o I I ~ ~O INn Oo ~
r~ n n o~
o ~ c ~. ~ v E
O O ~
m gi ~ E
c IL - n ~ ~ Y _ ~ x ~~ _ c ', ~-- _ U~3 ~ n-J _r n Y-~3"~Q V ~_y QQ_~ -3Jc~ ~_ CW~:^
N _ _ ~ ~ ~ n ~ u - D D ~ ~ V ~ Co ~ o I t c Y ~ L
t ~ 1~ 3 3 ~ Ul m 2 IL ~ t ~ ~ ~ z 1 t In the ~bove Table III It can be ~een from Run~ No. 1 and 2 that an adhe~lvo compo~ltlon contalnlng ~olcly a low denslty cthylene polymer, a butene-1 copolymer and a tacklfler aY thelr ~ole baslc constltuentY I 9 not partlcularly -~ultable a~ a hot melt adhoolvo. In Run No. I
the composltlon was un~table. The compo~ltlon of Run No. 2 had a vlscoslty 90 hlgh that It was practlcallY Imposslble to determlne whether or not separatlon of the components had occurred. Deslrably, a hot melt adheslve should possess a vlscoslty below about 15,000, preferably In the range of about 500 to about 10,000 for ease of applIcatlon to a Yubstrate. A value of 39.250, aY obtalned In Run No. 2, Is far too high to render the adhe~lve as a practIcal one for commerclal use. Moreover, whlle the peel ~trength was satlsfactory when the substrates were hlgh denslty polyethylenes, fallure wa~ encountered when polypropylene subYtrates were used. The presence of wax ln the varlous composltlons ln Runs Nos. 3 to 7 falled to Improve thelr propertleY or performance characterlstlcY. The compoYltlon of Run No. 8 contalnlng solely a low denslty polyethylene, tacklfler and wax, but no butene-1 copolymer was stable and had no ~atlsfactorY adheslve propertles. The addltlon of a low molecular welght polybutene In Run No. 9 to a compo~ltlon slmllar to Run No. 8 was also ~table but falled as an adhe~lve wlth polypropylene and Kraft paper _19_ . . .

sub~trates. Run No. lO la s1mllar to Run No. 9 and alao falled as an adhealve ualno polypropylene aubatratea.
Table IV clearly ahowY that when the adhealvo composltlon of thl 9 lnventlon contalna the requlred components, that 19, a low denslty ethylene polymer, a butene-l copolymer, a hydrocarbon tacklfler and a low molecular welght llquld polybutene ~Runs Noa. 11 and 12~, and wax as an addltlonal component to reduce lts vlsco~lty (Runs Nos. 13, 14 and 15), the adheslve 19 stable and exhlblts excellent adheslve propertles.

; -20-i304s29 n 888 ~ o I 8o ~ n n o n n ~ n n o 8 'O N~N ~ ~ ,N, 3 ! 8. 8. . ~ o N ~o m ~ ~ o u ! n n n N n o ~ ~ ~n ~ j 8 o 8 o ~ I O ~0~ O N n n ~ n 5~ ' 3i ! n n n ~e n o n O m N ~ ¦ g g g ~ ~ ~ g O ~ Y N nO n, ~ n m 1~ u~ ! nno oo ~n nno ~l U - ~ N n O O o Y ng~ $O nm ~L~ l v E

n n - n c- n a r ~ ; ~ c o ~ ~ g ~ ~o o ~ y j c ~ 3 ~ X Y N " ~ f ~ n Z ~y 3 ~ ~ co~ o ~ o ~ g I m ~O ~ -3~ O~ ~O~ o 1 3 . .

~304529 Table V show~ that oven whon a dlfforont polybuteno la used and the amounta of tho componont~ aro varlod, a ~tablo adheslve dl~playlng excellent adhe~lve propertle~ 1 obt a I ne~ .

,' , .

l304æs ! ~i n ~ % I ~ I O N ~

o ~~ n n 8 1 8 1 ~ o ~ ~ ~ 8 ~} n ~c ~ r-~.n o o _ N N
>. o 1~ o 1 8 8 8 1 8 ~ o ~ 8 N n N
¦ Nn o 8 nN N ~
c m _ ¦ n o n o o o ~ 3 n N N
1~. . ll o _ V I C
O L ¦ ~
n I n_ D
_- I C; o N n n N ~i O
D .~ O C _ O I --~ ;0 EL
~ _ C L L O a ~ g I ~ m Y ~ L l;
C~ ~ ~ L ~ n ~; Z
i ,ip./ ., ~

i 3 ~ 5~29 The runs ln Table VI aro ~Imllar to Run No. 16 In Tablo V oxcept that varlou~ tacklflers ~Runa No. 20 to 25) and comblnatlons of tacklflers ~Runs Nos. 26 and 27) were u~od.
The same excellent results were obtalnod. Peel strength tests were not carrled out In all of the substrates In Run~
No~ 21 to 26. because It would have been expected that excellent results would have been obtalned In llght of the prevlous runs and Runs No~. 20 and 27 In Table VI.

i., . . ~

-" i304S29 N 88 ~n8 ~ S 8 N~ 8i n N ~
N 88 n ' ~ ' 8 ' 51 8 ~

N1 8 8I ~ ~ 8 8 ~ ~ ~ ~ ~ æ ~ o O ~ ~ O N ~

N! 1 8 8 8 8 ~ OO N j~
~ ~ I n o ~ ~ o o 2 5 o NO ¦ o 8 ~ I I g I " o ~0 ~ ~ O N 5~
,W~ 0 I NO ~ n ~ ~ n 2~ ~'1 N¦ 8 8o ~ ~ ~ I O ,o, I O m 8 n I I
l NO n o o 8n -o ~J N 8 o.. - oN .~ ~ ~ ,O ~n Y N-O ~ n ~~ ~N
W

2 `8 8 1 8 ~ 8 ~ O o N N 1~ ~ ~8 ~n N-O n n N- NN-! llc O ~ ¦ I l D
~ 5 n I ^~ o Y
--a ` I 1~ 1 E ~ ^
qO ~ I 0~ y . ~ ~ I C 1 ~ 0 ~ O O ~ I U ~ I ~
N ~ gO ~gnN1~ I ~ I cO~n C .
C ~ D ~ O-- O o O. C ~ ' I ~
>' c u Z Z ~o u L o ~ 8 O D; y 1~ ~ W ~ ~ ~ W ~ ~ O 0 ~C ~ Z ~

i304æ9 Table V11 llluotratoo ~urthor aopocts o~ our novel adho~lvo compo~ltlon. Thu~ whllo wax wa~ prosent In Runa No~. 28 29 and 30 but not In Runa No~. 31 32 and 33 and the amount of low molecular welght llquld polybutene In Runa Nos. 31 32 and 33 wao groator than the othor run~ In Tablo VII a stable composltlon havlng oxcellent adhealon propertles waa obtalned In all cases. Although peel Ytrength testa were not carrled wlth all of the Yubstrates In RunY Nos. 31 32 and 33 It would have been expected that excellent reYults would have been obtalned ln llght of the other test results obtalned In Table VII.

i304529 R N N n o o g O N IB
r ~I I 1 8 1 1 1 8 ~ 8 O N i~ 5 ~ i~

~ n 5~ I N N n O O g o N m ~ ~
_ o > } 8 8 ~ _ n n o n o I I I I 1 1 888~ . ~_ . _mS~
~ ~ j m n5~ N n o 8 O N ~ N -a~ ~ j I 8 8 1 8 1 1 1 1 8 8 ~ ~ N N ~' 2 8 g I nn ~ nno 8 oN~N n~
u I _ _ N-- --~_ c~ mN nn o n n o ~o N8 Ii~
_ - n ol o I lC
_ I I
o ; L I I ~
I Ig n ¦ ~ I c~ o n j ~; n ~N' ~ ~ n 8 r ~ ~ ~ N ~ U5 Y ~ Y ~ -o x ~ I X 2i ~ ~
C ' D ~ L L O O t~ O -- I n P' Lo l S 1~ 0 ac ~; ~ C 111 o y U I L ~ o o j ~ ~ _ O j ~I~u~_ ~ ~ I u~z ~ 1 1~

:

~' -``` i30~529 Table VIII cloarly ~how~ that tho componont~, and tho amount~ thereof, makln~ up the novel adheslve composltlon clalmed hereln can be varled over a wlde ranse and a stable compo~ltlon posqes~lng excellent adheslve propertles wlll still be obtained.

`` 1~04529 ~i n ~ n 8 ~ ~ 8 ~ ~~o~ I ~0 ~ n o d N ~ 8 o u I I oo I I oo ~ ~xmo I N
~ c ~ 1 8 QO O~r ~ O-~ . noo m j n n o o o o N N m ~ Ij o ~j n ~. ¦ 8 8 ~ ~ 8 8 ~ ~ ~ `Yo ~ - ~n a~ ' ~, j n n n ~
~c~ ~!
~ ~ n o I n n ~ ~ ~ 8 ~o ~~0 nN n 8 ~ _ m ID
D ~ E~ 8 m ~ ~ n n n ~1 o n I oo o oo ~ ~o o l~no u I I I I o 8 Yo NN ~ I ~ n o w ~ oo I I oo I o - Y~o I ~ n o n n n o o o O N j~ N N ~0 o O O ~ jE
m ~ " i I ~ _ u n ij o n _ I n n j; _ O o ~ 3 ~ , I D E n x o ~ ~ n n N ; U ¦ D 11~ _ ~ ~ O O ~ L N t~ O -- ~ O O ~ Lo i ~ ~ 3 ~ ~ ~ D O n ~ ~ o I D ~ y ~11 ~ ~ I; ~ l~ -~ _ O ~ g ~ ~ O L I _ ~ Z O ¦ ~ _ : .

~3~529 ,. . ~

RunY Ylmllar to tho runa carrlod out In Tables Noa. IV
to ~lII were mado ~ut whereln tho low molocular welght llquld polybutenes were replaced wlth an amorphou~
polypropylene. The data ~o obtalned are ~ummarlzed below ln Tables IX, X and XI.

.
;

---" i304SZ9 ' ~n8,,, 88~, ~ 0 8n - No~
j ~ ~ N O N--IDN----~1 `
n; j ~ o ~ 8 1 ~ ~ 8 N ;~ g g 2 w~
0 N~ 1 8 n o I I o I ~ Yo 3E~ ~ N ~ ~ n ~, æ 8 -- N
e~ _ I 0 0 0 0 0~
L ~ I nno I ~ I o I I ~ . Y~t.N ~-~
~ I ----N O01~ mN--N N
~0 o 000 0 0 ~--0~NmO
o ~ n n n ~ ~ O I I I oO o n ~ ~ N n IN
----N

O ¦ E
~ ~ I_ o ~ ~ I wn~ ~
n- I nc ~
~~ I n_ __ ~ ~ t ~ j ~ c ~ E--N ~ ~E o n ~ ~ ~ 2 2 I ~ Y I o w ~ r~
~1~ O L Y Y ~ O O -- ~ IL O ~ O I
w~uo . _ce 1~ o.l n~.u ~ 1_ e, 1~ o e U y ~ ~ e ~ VO ~ t 1 Ic J o. ~ ~ w ~ a u~ 2 ~

. ~ -31-.

~`:

~3045~9 æ n I n 8 1 ~ 1 8 ~ ~ 8 ~ N

5~; 1 ,o, o~ " O,, ~ ~ ~
N h N llt g n n I In o 8 1 1 1 ~ ~ ~ ~ æ n ~ o~ ~o N ~ n 13 ~ o o ~

¦ n ~ ~ o 8 1 1 1 1 8 o ~ ; 3!~ N r--- I

c S~ 3I n n I O I O I I ~ I OD
~I NN ~ n _ n _ _ x _ ~ 111 3 111 1 11~ O I O I I I ~ Y o 3~ ~
æ ,, I N N N ~ . _ n n N
o ¦ 8 1 8 8 1 8 1 1 8 ~ gO o ~ n ~ n ~ I _ _ o I o 8 1 o I I ~ ~ ~ Yo ~ g ID I 1 3 "N on n o o n _ fi m a~ ~-~ ~ o o O , ~ ~ . ô I i C

~ j " ,~ E- ~

N ~--~ U 3 C ~ ~e --~ U O O O O ~ ~ ~ I -- ~ O
~ 3 .~ g, o, o, o, _ o _ o I _ ~. o . o I
~ `~ ~ ~ OE ~ ~ ~ o' I ~; ~
a 0 ~ 1 0 ~ ~ z . ~ -3;~-: .

~304æs n ~ I ~ o~ ~ n~ 8 O N ~
~ o ~
~!~ ~Y j ;~ ~ B ~ I a o ~ o I O O o ~ 3 ~ o o o~

~, c C

n ~ o ~ ~ !u ~ ~c~ n _ ~ o ~ ô o II ~ ~
c ~ ~ O In ~m Y
9 ~ 3 c i5~ '~ ~ z ,= .,. / ~ ., - . --" i304S29 The data In Table~ IX, X and XI ~how th~t the samoexcollent polymor blond~ woro obtalnod whon an amorphou~
polypropylene was used In place of the low molecular welght llquld polybutone. Although performance data worc not takon In connectlon wlth all of the substratos In each of tho run~
In Table X, lt would have been expectod that In vlew of the results obtalned ln Table~ IX and XI, tho same excellont re~ults would stlll have been obtalncd had the remalnlng runs been fully carrled out.
An addltlonal serle~ of runs was carrled out whereln the novel polymer blend clalmed herein was prepared uslng addltlonal low denslty ethylene polymers. As the data ln Table XII show. excellent results were agaln obtalned.

; -34-tii I ~ I t o g N ~j O ~ ~

9; 1 ~ n I ln g o ~~ ~ o n o ~ ~ ~
x ~ rt -- ~ N
n ~ t o oooo ~r Y~o~ mo n I I ~ n o o O o N 8 ~

Q
o y W

ô I t o, i - 5 ' ~ , ¦ t ~
o ~ j I o - t ~, I n_ o t _ ~
L I n I ~ ~ -~i t lq IL t ;~ ~ ~ lq ~ ~ ~ t u ~ ~ ¦ c I lq ~ ~ o o t ~ IL o ~ o t ~ 2i ~
~ o 3; ~ vo o ~
Q ~ J ~ Q I~I Q ~ ~- Q I ~ z Q I i~

1:~0~529 Obvloualy, many modlflcatlon~ and va~latlona of the Invontlon, ao horolnabove oot forth, can bo mado wlthout departlng from the oplrlt and scope thereof and therefore only such llmltatlons should be Impo~ed as are Indlcated In the appended clalms.

Claims

1. A compatible polymer blend comprising a low density ethylene polymer, a copolymer of butene-1 and from about 1.5 to about 20 weight percent of an olefin selected from the group consisting of ethylene and propylene, a hydrocarbon tackifier and a low molecular weight polymer selected from the group consisting of a low molecular weight liquid polybutene, an amorphous polypropylene and mixtures thereof.

2. The polymer blend of claim 1 wherein said copolymer is a copolymer of butene-1 and ethylene.

3. The polymer blend of claim 2 wherein said low molecular weight polymer is a low molecular weight liquid polybutene.

4. The polymer blend of claim 2 wherein said low molecular weight polymer is an amorphous polypropylene.

5. The polymer blend of claim 1 wherein said amorphous polypropylene is obtained as a byproduct during the production of crystalline polypropylene.

6. The polymer blend of claim 1 wherein said amorphous polypropylene is obtained as a direct product of the polymerization of propylene without the formation of crystalline polypropylene.

7. The polymer blend of claim 2 wherein said low molecular weight polymer is a mixture of a low molecular weight liquid polybutene and an amorphous polypropylene.

8. The polymer blend of claim 7 wherein said mixture contains from about 97.5 to about 2.5 weight percent of amorphous polypropylene.

9. The polymer blend of claim 7 wherein said mixture contains from about 75 to about 40 weight percent of amorphous polypropylene.

10. The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.94 and a melt index in the range of about 3 to about 5000 grams/10 minutes.

11. The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.93 and a melt index of about 20 to about 500 grams/10 minutes.

12. The polymer blend of claim 2 wherein said butene-1 copolymer has a melt index in the range of about 0.3 to about 2000 grams/10 minutes.

13. The polymer blend of claim 2 wherein said butene-1 copolymer has a melt index in the range of about 3.0 to about 2000 grams/10 minutes.

14. The polymer blend of claim 2 wherein said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 150°C.

15. The polymer blend of claim 2 wherein said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 140°C.

16. The polymer blend of claim 2 wherein said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 500 to about 5000.

17. The polymer blend of claim 2 wherein said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 1300 to about 3000.

18. The polymer blend of claim 2 wherein said low molecular weight polymer is an amorphous polypropylene having a crystallinity of les than about 10 weight percent and a molecular weight in the range of about 300 to about 20,000.

19. The polymer blend of claim 2 wherein said low molecular weight polymer is an amorphous polypropylene having a crystallinity of les than about five weight percent and a molecular weight in the range of about 1000 to about 15,000.

20. The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.94 and a melt index of about 3 to about 5000 grams/10 minutes.
said butene-1 copolymer has a melt index in the range of about 0.3 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 150°C and said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 500 to about 5000.

21. The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.93 and a melt index of about 20 to about 500 grams/10 minutes, said butene-1 copolymer has a melt index in the range of 3.0 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 140°C and said low molecular weight polymer is a low molecular weight liquid polybutene having a molecular weight from about 1300 to 3000.

22. The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.94 and a melt index in the range of about 3 to about 5000 grams/10 minutes, said butene-1 copolymer has a melt index in the range of about 0.3 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 150°C and said low molecular weight polymer is an amorphous polypropylene having a crysytallinity of less than about 10 weight percent and a molecular weight in the range of about 300 to about 20,000.

23. The polymer blend of claim 2 wherein said low density ethylene polymer has a density of about 0.88 to about 0.93 and a melt index in the range of about 20 to about 500 grams/10 minutes, said butene-1 copolymer has a melt index in the range of about 3.0 to about 2000 grams/10 minutes, said hydrocarbon tackifier has a ring and ball softening point in the range of about 10° to about 140°C and said low molecular weight polymer is an amorphous polypropylene having a crystallinity of less than about five weight percent and a molecular weight in the range of about 1000 to about 15,000.

24. The polymer blend of claim 2 wherein said components are present in the following amounts.

Weight Percent Low Density Ethylene Polymer 2.5 - 40 butene-1 Copolymer 5 - 60 Hydrocarbon Tackifier 5 - 40 Low Molecular Weight Liquid Polybutene or 5 - 60 Amorphous Polypropylene 5 - 87.5

25. The polymer blend of claim 2 wherein said components are present in the following amounts:
Weight Percent Low Density Ethylene Polymer 5 - 30 Butene-1 Copolymer 10 - 50 Hydrocarbon Tackifier 10 - 35 Low Molecular Weight Liquid Polybutene or 10 - 40 Amorphous Polypropylene 10 - 75

26. The polymer blend of claim 24 wherein the weight ratio of low density ethylene polymer to the butene-1 copolymer as in the range of about 9:1 to about 1:9.

27. The polymer blend of claim 25 wherein the weight ratio of low density ethylene polymer to the butene-1 copolymer is in the range of about 1:3 to about 3:1.

28. The polymer blend of claim 2 wherein a paraffin or microcrystalline wax is also present.

29. The polymer blend of claim 2 wherein an antioxidant is also present.

30. The polymer blend of claim 2 wherein a paraffin wax or microcrystalline wax and an antioxidant is also present.