DE3108895A1 - MODIFIED OLEFIN POLYMERS AND THEIR USE AS ADHESIVES - Google Patents

Description

: Ö £ _s ; BEaCr ρΐΡΙ, .- ING. STAPF DIPLVING. SCMWABE DR: DR.SANDMAIR 3 1 QO 8 9

PATENTANWÄLTE PO Box 8602 45 8000 Munich 86

Attorney-Afcte: 3! 36! - ^ ^

MONSANTO COMPANY ST. LOUIS, MISSOURI / USA

Modified olefin polymers and their use as Adhesives

EPO GOPY

β (039) 938272 Tdejnmune: Bink accounts: Hypo-Btnk Munich 4410122850

938273 BERGSTAPFPATENT Munich (BLZ 70020011) Swift Code: HYPO DE MM

938274 TELEX: B »yei Vereinsbank Munich 453100 (BLZ 70020270) 983310 052456OBERGd _ Postscheck Munich 65343-808 (BLZ 70010080)

13QPR7 / 0S8 5

- r-

Description

The invention relates to improved olefin polymers, in particular Olefin polymers »modified with maleic acid amide derivatives will. It also relates to bonded products made of metal and polymer material.

The modification of olefin polymers with unsaturated carboxylic acids gives polymer formulations with superior adhesion to various substrates; see e.g. US-PSs 3,483,276 and 3,987,122. Improving the adhesion of elastomers to metal by curing the elastomer with a Free radical curing system in the presence of N-maleic acid amide or N-maleic acid imide compounds is also known; see US-PS 3,502,542, however, to all possibilities To be able to exploit products made of polymer material that is glued to metal, even better adhesion is required.

It has now been found that an α-monoolefin polymer which modified by reaction with a substituted maleic acid amide, a polymer formulation with superior adhesion especially on metal substrates. The modified monoolefin polymer of the present invention contains the reaction product of an olefin polymer, preferably a thermoplastic Olefin polymer, and about 0.1 to 20 weight percent one

substituted maleic acid amides of the formula

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-, το ο ο

Il It It

a) HO-C-CH = CH-C-NH-R-C-OH

wherein R is a straight or branched alkylene radical with 1 to 18 carbon atoms, or the formula

0 0

Il Il

b) (HO-C-CH = CH-C-NH-) _O R '

2 Ti

where η is zero or 1, and R 'is straight or branched Alkylane radical with 2 to 18 carbon atoms, or Represents arylene having 1 to 12 carbon atoms. Suitable Arylene radicals include phanylene and with lower alkyl, Lower alkoxy or halogen, preferably chlorine, substituted Phenylan. Lower alkyl is an alkyl radical with 1 to Carbon atoms. Alkylene radicals with up to 12 carbon atoms are preferred.

The modified oil finishes according to the invention can easily by high-speed mixing of the olefin polymer with substituted one Maloinaäureamids, preferably in the presence of one Radical generator. For mixing the ingredients and conventional plastic kneading devices such as a mill can be used to carry out the reaction Banbury mixer or twin screw press related will. Depending on the temperature ;, type of olefin polymer, the substituted Maleic asnidi; and the radical generator are sufficient generally mixing sides of 1 to 30 rain to make the reaction essentially complete.

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EPO COPY

Preferably the ingredients are allowed to react at a temperature above the pour point of the olefin polymer. To promote of the reaction is generally a (free) radical generator, such as a peroxide, in amounts from about 0.1 to 50 parts by weight per 100 parts by weight of substituted Maleic acid amide present. The amount of the radical generator is kept as small as possible to avoid excess crosslinking of the olefin polymer or, in the case of branched olefin polymers such as polypropylene, excessive degradation of the polymer to avoid. Generally, the radical generator makes 5 or less, preferably 1 or less parts by weight per 100 parts by weight of olefin polymer. Preferred modified polymers according to the invention contain the reaction products of olefin polymer and about 0.2 to 10% by weight substituted maleic acid amide.

Suitable olefin polymers are amorphous or crystalline, practical saturated homopolymers or copolymers of C_- to Cg-α-monoolefins. Thermoplastic crystalline olefin polymers are particularly preferred. An important subgroup of useful olefin polymers includes high solids Molecular weight from the high pressure or low pressure polymerization of monoolefins or their mixtures. Examples such polymers are the isotactic or syndiotactic monoolefin polymers, examples of which are are generally available. Satisfactory olefins

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include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 2-methyl-2-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, 5-methyl-1-hexene and mixtures thereof. Commercially available thermoplastic Polyolefin resins such as polyethylene, polybutene-1 and polypropylene, as well as mixtures thereof, can advantageously be used in the process according to the invention, wherein Polypropylene is preferred. Copolymers of two or more are also suitable for the process according to the invention more olefins, with copolymers of ethylene and propylene being preferred.

The substituted maleic acid amides which are useful for the preparation of the modified monoolefin polymers according to the invention can be used as derivatives of 4-oxo-2-butenoic acid, ie 4- (carboxyalkylamino) -4-oxo-2-butenoic acid and U, H '- (alkanediyldiamino or Phenylenediamine) bis-4-oxo-2-butenoic acid. 4,4'- (Hydrazo) -bis-4-oxo-2-butenoic acid can also be used to produce modified polymer. For the sake of simplicity, however, they are referred to here as maleic acid amide derivatives.

Examples of the substituted maleic acid amides of the formula a) which are suitable for the process according to the invention are:

N- (carboxymethyl) maleic acid amide N- (2-carboxyethyl) maleic acid amide N- (2-carboxypropyl) maleic acid amide

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N- (3-carboxypropyl) maleic acid amide N- (2-carboxybutyl) maleic acid amide N- (3-carboxybutyl) maleic acid amide N- (U-carboxybutyl) maleic acid amide N- (5-carboxypentyl) -maleic acid amide N- (6-carboxyhexyl) -maleic acid amide N- (7-carboxyheptyl) -maleic acid amide N- (8-carboxyoctyl) maleic acid amide

N- (4-carboxy-1,1,3,3-tetramethylbutyl) maleic acid amide

N-C10-carboxydecyl) maleic acid amide N- (12-carboxy dodecyD-maleic acid amide N- (15-carboxy pent adecyD-maleic acid amide N- (18-carboxyoctadecyl) maleic acid amide

Examples of the substituted maleic acid amides of the formula b) which are suitable for the process according to the invention are:

N, N'-dimeric acid amide N, N '- (dimethylene) -dimalic acid amide N, N '- (1-methyl-1, 2-ethanediyl) -dimaleic acid amide N, N * - (trimethylene) -dimalic acid amide N, N '- (1-Methy1-1,3-propanediy1) -dimaleic acid amide N, N '- (tetramethylene) -dimaleic acid amide

N, N '- (2,2-Dimethyl-1,3-propanediy1) -dimaleic acid amide

N, N '- (pentamethylene) -dimalic acid amide N, N ^l - (hexamethylene) -dimalic acid amide

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N, N · - (Heptamethylene) -dimaleic acid amide N, N ¹ -COctamethylene ^ -dimaleic acid amide N, N '- (decamethylene) -dimalic acid amide N, N ^l - (dodecamethylene) -dimaleic acid amide N, N' - (pentadecamethylene) -dimalic acid amide N, N'- C octadecylmethylene) -dimaleic acid amide N, N '- (1,2-phenylene) -dimaleic acid amide N, N' - (1,3-phenylene) -dimaleic acid amide N, N - (1,4-phenylene) -dimalein acid amide HjN '- ^ - Methy 1-1,2-phenylene) -dimalein acid amide N, N' - (5-methyl-1,3-phenylene) -dimalein acid amide N, N '- (5-methoxy-1, 3-phenylene) -dimaleic acid amide N, N '- (2-chloro-l, ^l + -phenylene) -dimaleic acid amide

N, N ^l - (5-tert-butyl-1,3-phenylene) -dimaleic acid amide

N, N '- (1,2-naphthylene) -dimalainic auraamide

Any radical generator that promotes the reaction between olefin polymer and substituted maleic acid amide is suitable for the process according to the invention. This includes azides and inorganic or organic peroxides. Examples of suitable free radical generators are dicumyl peroxide, benzoyl peroxide, 2 ₉ 5 ~ dimethyl-2,5-bis- (tart.-buty! Peroxy) hexane, 1,1-bis (tert-butylpsroxy) -3,3 "5-trimethylcyclohexane, tris- [α, α-dimethyl-a- (tert-butylp@roxy) -niQthyl] -benzene, di-tert-butyl peroxide, lauroyl peroxide, cumene hydroperoxide, tert-butyl hydroperoxide, α, a ' * Bis- (tert-buty! Peroxy> -hexane, pinane hydroperoxide,

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p-methane hydroperoxide and azobisisobutyronitrxl.

One embodiment of the invention includes reinforced products made of a metal part with a polymer material glued to it. Increased adhesion between the metal and the polymer material is achieved by promoting adhesion at the interface between the metal part and the polymer material Provides amount of the modified polymer of the invention. The modified olefin polymer of the present invention can be exactly like conventional adhesives can be applied, e.g. as a hot melt adhesive with direct contact at a temperature above the softening or pour point of the modified Polymer or the polymer material containing modified polymer. The modified polymer can then be sent to the Migrate the interface and create a bond after cooling. The modified polymer can be applied to the surface also applied as a solution or suspension and then evaporated the solvent. Lots of the modified one Olefin polymer, which is the adhesion between the metal and the polymer material increased is satisfactory for the manufacture of the improved products of the invention. The amount required varies depending on the type of metal or polymer material used, but it is easy to test ascertain. The amount is gradually increased until sufficient adhesion is achieved. To the invention reinforced products include composites, laminates

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la

-yr-

■ materials and objects in which the metal is present as a foil or j continuous or discontinuous fiber. The ι designation "polymer material" does not include anything

: Te olefin polymer is a that remains after a portion of the "olefin polymer has been modified by reaction with substituted maleic acid amide.

In addition to the olefin polymer, all other polymers can also be used as polymer material for the production of bonded metal products are used, which are made to adhere to the metal with the aid of the modified olefin polymer according to the invention will. Exemplary suitable polymer materials are nylon, polyester, polyurethanes, styrene acrylonitrile resins, polystyrene, ABS resins, as well as hardened or unhardened rubber.

All metals are suitable for the production of products according to the invention, but especially those which are bi- or; are polyvalent and have a flow temperature above 200 ⁰ C. Preferred metals are iron, aluminum, zinc, copper and their alloys such as brass and steel, with aluminum being particularly preferred.

In general, it is necessary to apply the adhesive layer that to be bonded surface of the metal substrate and the other substrate, if such is present, via the flow or To heat the softening temperature of the adhesive.

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EPO COPY

The following are preferred embodiments of the invention described.

Polypropylene is modified by the action of a substituted maleic acid amide in the presence of a free radical generator. For example, 100 parts by weight of polypropylene (Profax 6723, melt flow 0.8, ASTM D-1238, Cond. L) and 5 parts by weight of the stated reactants are ^{kneaded at 80 rpm at about 180 °} C. in a Brabender mixer. After a homogeneous mixture has formed, 0.56 parts by weight of a radical generator, namely 2,5-dimethyl-2,5-bis- (tert-butylperoxy) -hexane, Lupersol-101, are added and mixed for a further 5 minutes. The modified polypropylene is removed, cooled in a press and examined either pure or mixed with other substances as a hot-melt adhesive.

A reinforced product is made by gluing two 0.127 mm thick aluminum foils (12.7 x 12.7 cm) with about 1 g of modified polypropylene or a mixture containing it. An aluminum "sandwich" is made from the two bonded with the modified polypropylene aluminum foils. By forcing at 210 ⁰ C and a pressure sufficient that forms an approximately 0.127 mm thick polymer interlayer. The sandwich is cut into strips 1 "C 2.5i + cm) wide. The force that is required to keep the two aluminum strips at 180 ^° C

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is

pull apart is measured with a tensile tester; a separation speed of l'Vmin (2.54 cm / min) applied. The adhesion values are recorded in pounds / linear inch. It becomes the adhesion of aluminum to modified Polymer (modified PP) and a mixture with a thermoplastic elastomer preparation (TE / PP mixture) ucht.

The thermoplastic elastomer preparation is produced by means of dynamic vulcanization as described in US Pat. No. 4,130,535, however, part of the polypropylene is replaced by modified polypropylene, and a phenolic hardener is also used. The thermoplastic elastomer composition contains (based on weight) 50 parts EPDM rubber (Epsyn 70A), 37 _a 5 parts of polypropylene (Profax 6723) and 12.5 parts of modified polypropylene. To cure the rubber, 5 parts of phenolic hardening resin, ie SP-1045, and one part of hardening activator, in this case zinc oxide, are used.

The results are shown in Table I. material 1, 2 and 3 are used as controls, the rsaktantan are maleic acid, maleic anhydride and 1,3-phenylenebissaleinimide, respectively. Materials 4 to 7 are exemplary of polypropylene that has been modified with dimalaic acid amide derivatives. material 8 and 9 are examples of N-carboxyalkyl maleic acid

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amide modified polypropylene. It can be seen from the data that polypropylene modified with a dimeric acid amide derivative shows superior adhesion when used in its pure form and that polypropylene modified with an N-carboxyalkyl maleic acid amide shows superior adhesion in a thermoplastic elastomer blend. The test with material 4 x was repeated, instead of 5 only 2 parts of N, N ^f - (hexamethylene) -dimaleic acid amide are used together with the polypropylene. The adhesion values are 6.7 pli (pounds per linear inch) for the modified PP, and 8.0 pli for the TE / PP mixture.

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Table I.

co ο ο σ>

Material no. 1 2 3 4 5 6 7 8 9

Respondents

Adhesion to aluminum, pli

Maleic acid

Maleic anhydride

1,3-phenylenebismaleimide

N, N '- (hexanemethylene) - ⁽ ii ⁿⁱ aleic acid amide

N, N ^l - (dodecamethylene) dimalic acid amide

N, N '- (1, H-phenylene) -dimaleinic acid aTT> id

N, N '- (1,3-phenylene) -dimaleic acid amide

N-CCarboxymethyl-maleic acid amide

N-C 3-carboxypropyl) maleic acid arid

Modified PP TE / PP mixture 0.5 6.0 2.5 7.8 0.24 0.4 6.0 8.5 6.0 6.5 8.0 2.0 ' 7.0 8.5 1.0 14.7 0.25 12.0

IB -yr-

Other modified polypropylene formulations were made and tested as in Table I, but the polypropylene was Profax 6523 (melt index 0 and 1.48 parts Radical generator used. The results are shown in Table II.

Table II Liability a.Aluminium, pii TE / PP mixture material
No. Respondents 23.5
13.5 1
2 N- (carboxymethyl) -male into the outer
reamid
N- (IO-carboxydecyl) -male
acid amide

The promotion of adhesion by mixing uncured rubber and modified polypropylene of the present invention is shown in Table III. The modified polypropylene is made from Profax using the same process as above 6 523 manufactured. In materials 1 to 5, for every 100 parts of polypropylene, 5 parts of N- (carboxymethyl) maleic acid amide are added (CMMA) and 1.48 parts of organic peroxide (L-IOl) are used. In Materials 6 to 7, for every 100 parts of polypropylene, there is 10 parts of N- (carboxymethyl) maleic acid amide and 0.87 parts organic peroxide (L-101) is used. In material 8 tis Il

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Materxal
No. Modif 1 CMMA 2 CMMA 3 CMMA ! + CMMA 5 CMMA 6th CMMA 7th CMMA 8th HMDMA 9 HMDMA 10 HMDMA 11 HMDMA 12th PDMA 13th PDMA

Table III

modified PP EPDM (weight components)

^ω 6 CMMA 100

° ti

ο 7 CMMA 70 ου οζ, ο _ί ^

2 8 HMDMA 100

_ο _ 80

C "10 HMDMA 70

cn II HMDMA 60

^ Mixture of 25 parts modified PP and 75 parts unmodified PP. t m l ^

to

O j

Ό '
O

<■ y ■

Rubber aluminum adhesion,
Pli <0.5 - 3.5 20th 10.0 30th 8.5 60 6.5 80 9.0 - 32.5 30th 6.0 - 10.0 20th 14.5 30th 12.5 HO 11.0 - 26.0 30th

5 parts of N, N - (Hexanethyj in) -dimaleinsäureamid (HMIMA) and 0.56 T-Lie organize ies peroxide with 100 parts Polypropylene j ar R <Aktion gebrv: ht. In Materini 12 to 13 5 parts of «N, N - (1,4-Pheny] 2n) -dimaleic acid amide (PDMA) and 0, i) 6 Te; Ie organic peroxide per 100 parts Polypropylene used. The modified polypropylene is coated with uncured EPDM rubber (ethylene-propylene-norbornene terpolymer, Epsyn 70.) in the specified ratio (all parts based on the weight) in a 3rabends mixer mixed over the melt temperature door of the polypropylene. As described above, you can make an aluminum sandwich by heating the adhesive preparation between two Presses aluminum foils. Adhesion is measured as above. It can be seen from the results that the inclusion of uncured rubber in as modified polypropylene the liability ai ■ Alu-dnium wesen .icl increases. D; e Daren er-ebe furthermore, that mm overweight receives mg if df ^ rubber with 30 ".ewict tsante Ilen ό 00 Gewiehtr.ant-: ile Po ^ ypr pylen, irodified pol ^ propy in and unhardened rubber taken together, is present.

End of description

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Claims (22)

Claims 1. Modified olefin polymer, characterized that it is the reaction product of monoolefin polymer and about 0.1 to 20% by weight of a substituted Contains maleic acid amide which has the formula 0 0 0 If Il t! a) HO-C-CH = CH-C-NH-R-C-OH wherein R is a straight or branched alkylene radical having 1 to 18 carbon atoms, or the formula 0 0 Il Il b) (HO-C-CH = CH-C-NH -) _ R ' 2 η where η is zero or 1, and R ^{1 is} a straight or branched alkylene radical having 2 to 18 carbon atoms or arylenes having 1 to 12 carbon atoms. 2. Polymer according to claim 1, characterized in »that the olefin polymer is a thermoplastic, practically saturated homopolymer or copolymer of a C ^ - to C _ß -α-olefin. EPO COPY HJ -12 Θ (089) 988272 Telegrams: ... ^ q / η Γ Q C Bank accounts: Hypo-Btnk Munich 4410122850 --- ^9S 8273 BERGSTAPFPATEi ^ iJcpJiib / / U 0 OQ (BLZ 70020011) Swift Code: HYPO DE MM 3. Polymer according to claim 2, characterized in that it is the reaction product of about Contains 0.2 to 10% by weight of a substituted maleic acid amide of the formula a). 4. Polymer according to claim 2, characterized in _> that it contains the reaction product from about 0.2 to 10% by weight of a substituted maleic acid amide of the formula b), in which η is 1. 5. Polymer according to claim 3, characterized in that the olefin polymer is crystalline Is polypropylene. 6. Polymer according to claim 4, characterized in that that the olefin polymer is crystalline polypropylene. 7. Polymer according to claim 5, characterized in that R is an alkylene radical with 1 to Means 12 carbon atoms. 8. Polymer according to claim 6, characterized in that R ^{1 is} an alkylene radical having 2 to 12 carbon atoms. - / 3 130067/0585 ^. ". EPOCOPY 9. Polymer according to claim 6, characterized in that R ^{1 is} 1,3-phenylene. 10. Polymer according to claim 6, characterized in that R ^{1 is} 1,4-phenylene. 11. Polymer according to claim 7, characterized in that R is methylene. 12. Polymer according to claim 8, characterized in that R ^{1 is} hexamethylene. 13. Improved product made of a metal part and a polymer material glued thereon, characterized in that at the interface between the metal and the Polymermatarial an adhesive is present, the adhesion promoting amount of the modified polymer according to claim 1 contains. 14. Product according to claim 13, characterized that the metal part consists of iron, aluminum, zinc, copper or alloys of the same. 15. Product according to claim 14, characterized that the polymer material contains olefin polymer. - / 4 130067/0585 EPO COPY 16. Product according to claim IH, characterized in that that the polymer material contains rubber. 17. Product according to claim 16, characterized that the rubber is EPDM rubber. 18. Product according to claim 15, characterized in that the olefin polymer is polypropylene 19. Product according to claim 18, characterized in that the metal is aluminum. 20. Product according to claim 16, characterized in that the adhesive is the modified The polymer of claim 7 is. 21. Product according to claim 1> 4, characterized in that that the adhesive is the modified polymer according to claim 8. 22. Product according to claim 14, characterized in that R ^{1 is} phenylene. - / 5 130067/0585