High performance pressure-sensitive adhesive polymers

• US 4,812,541 A
• Filed: 12/23/1987
• Issued: 03/14/1989
• Est. Priority Date: 12/23/1987
• Status: Expired due to Term

• Current Assignee: Avery Dennison Corporation
• Original Assignee: Avery Dennison Corporation
• Inventors: Smith, Colin, Plamthottam, Sebastian S., Mallya, Prakash
• Primary Examiner(s): Michl, Paul R.
• Assistant Examiner(s): WALKER, ALEXANDER
• Application Number:
  US07/138,722
• Time in Patent Office: 447 Days
• Field of Search: 526/264, 526/273
• US Class Current: 526/264
• CPC Class Codes: C08F 220/1808 C8-(meth)acrylate, e.g. isooctyl (meth)acrylate or 2-ethylhexyl (meth)acrylate
• CPC Class Codes: C09J 133/068 containing glycidyl groups
• CPC Class Codes: C09J 2301/302 the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C
• CPC Class Codes: C09J 7/385 Acrylic polymers

Abstract

Pressure-sensitive copolymers based on acrylic monomers are provided with high adhesive performance characteristics by the inclusion of a synergistic amount of an N-vinyl lactam monomer and a glycidyl monomer with the bulk of the monomers being an alkyl acrylate and/or methacrylate esters.

Claims

1. A pressure-sensitive adhesive comprising a copolymer comprising on a copolymerized basis from about 55 to about 85% by weight of a monomer selected from the group consisting of alkyl acrylate esters and alkyl methacrylate esters containing from 4 to about 12 carbon atoms in the alkyl group and mixtures thereof, from 0 to about 35% by weight of an alkyl acrylate or methacrylate ester containing less than 4 carbon atoms in the alkyl group, from 0.01 to about 2% by weight of a glycidyl monomer, from about 1 to about 10% by weight of an N-vinyl lactam, and from 0 to about 15% by weight of an unsaturated carboxylic acid, said copolymer having a weight average molecular weight of at least about 200,000 and a glass transition temperature less than about -15°

C.

2. A pressure-sensitive adhesive as claimed in claim 1 which contains, based on the total weight of monomers, up to about 35% by weight, of a monomer selected from the group consisting of polystyryl ethyl methacrylate, aceto-acetoxy ethyl methacrylate, styrene, alpha olefins, vinyl esters of alkanoic acids containing more than about three carbon atoms and mixtures thereof.

3. A pressure-sensitive adhesive as claimed in claim 1 in which the alkyl acrylate is 2-ethyl hexyl acrylate or isooctyl acrylate.

4. A pressure-sensitive adhesive as claimed in claim 2 in which the alkyl acrylate is 2-ethyl hexyl acrylate or isooctyl acrylate.

5. A pressure-sensitive adhesive as claimed in claim 1 in which the glycidyl monomer is selected from the group consisting of glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether and mixtures thereof.

6. A pressure-sensitive adhesive as claimed in claim 2 in which the glycidyl monomer is selected from the group consisting of glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether and mixtures thereof.

7. A pressure-sensitive adhesive as claimed in claim 3 in which the glycidyl monomer is selected from the group consisting of glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether and mixtures thereof.

8. A pressure-sensitive adhesive as claimed in claim 4 in which the glycidyl monomer is selected from the group consisting of glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether and mixtures thereof.

9. A pressure-sensitive adhesive as claimed in claim 1 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

10. A pressure-sensitive adhesive as claimed in claim 2 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

11. A pressure-sensitive adhesive as claimed in claim 3 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

12. A pressure-sensitive adhesive as claimed in claim 4 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

13. A pressure-sensitive adhesive as claimed in claim 5 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

14. A pressure-sensitive adhesive as claimed in claim 6 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

15. A pressure-sensitive adhesive as claimed in claim 7 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

16. A pressure-sensitive adhesive as claimed in claim 8 in which the N-vinyl lactam is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl caprolactam and mixtures thereof.

17. A pressure-sensitive adhesive as claimed in claim 1 in which the formed copolymer is cross-linked by exposure to heat, ionic additive, actinic radiation or electron beam radiation.

18. A pressure-sensitive adhesive comprising a copolymer comprising frm about 55 to about 85% of an alkyl acrylate ester selected from the group consisting of isooctyl acrylate and 2-ethyl hexyl acrylate, from about 0.01 to about 2% by weight glycidyl methacrylate, from about 1 to about 10% of a N-vinyl lactam selected from the group consisting of N-vinyl pyrrolidone and N-vinyl caprolactam, from about 5 to 13% by weight unsaturated carboxylic acid, and up to about 35% by weight methyl acrylate, said polymer having weight average molecular weight from about 200,000 to about 500,000 and a glass transition temperature less than about -15°

C.

19. A pressure-sensitive adhesive as claimed in claim 18 in which the formed copolymer is cross-linked by exposure to heat, ionic additive, actinic radiation or electron beam radiation.