Water borne pressure sensitive adhesive compositions derived from copolymers of higher vinyl esters

• US 6,426,151 B1
• Filed: 02/03/1999
• Issued: 07/30/2002
• Est. Priority Date: 11/12/1996
• Status: Expired due to Term

• Current Assignee: Ashland Licensing and Intellectual Property Llc
• Original Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Inventors: Kem, Kenneth Merle, Mao, Chung-Ling
• Primary Examiner(s): REDDICK, MARIE L
• Application Number:
  US09/243,776
• Time in Patent Office: 1,273 Days
• Field of Search: 428/520, 427/207.1, 427/316, 427/393.5, 156/60, 156/278, 156/306.3, 156/327, 156/280
• US Class Current: 428/520
• CPC Class Codes: C08F 218/10 of monocarboxylic acids containing three or more carbon atoms
• CPC Class Codes: C08F 220/06 Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof
• CPC Class Codes: C08F 220/12 of monohydric alcohols or phenols
• CPC Class Codes: C08F 220/14 Methyl esters , e.g. methyl (meth)acrylate
• CPC Class Codes: C08F 220/1808 C8-(meth)acrylate, e.g. isooctyl (meth)acrylate or 2-ethylhexyl (meth)acrylate
• CPC Class Codes: C09J 133/06 of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
• CPC Class Codes: C09J 133/062 Copolymers with monomers not covered by C09J133/06
• CPC Class Codes: C09J 2301/302 the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 428/31928 Ester, halide or nitrile of addition polymer

Abstract

The present invention is directed to improved flexibilized, plasticized polyvinyl chloride films bonded with a substrate by means of an aqueous based pressure sensitive acrylic adhesive emulsion polymers. Conventional emulsion based pressure sensitive adhesives were comprised of a copolymer comprised of polymerized units of acrylic esters and ethylenically unsaturated monomers, the copolymer having a T_g of from −15 to −70° C. The improvement in the aqueous based, emulsion polymerized pressure sensitive adhesives resides in the incorporation of polymerized units of a vinyl C_8-13 ester of a neo-acid into the adhesive. The vinyl ester is formed from a mixture of propylene oligomers and such vinyl ester is represented by the chemical formula: C_8-13H_7-27CO₂CH═CH₂. Preferably, the adhesive includes units of methyl methacrylate, butyl acrylate of 2-ethylhexyl acrylate and a carboxylic acid selected from acrylic acid or methacrylic acid.

Claims

1. In a process for forming a laminate comprised of a flexible plasticized polyvinyl chloride film bonded to a substrate by means of a water based, acrylic emulsion adhesive comprised of a copolymer having polymerized units of C_1-12 alkyl acrylates or C_1-12 alkyl methacrylates wherein said process comprises the steps of coating said water based acrylic emulsion onto the flexible plasticized polyvinyl chloride film or onto the substrate, drying the resulting film and then laminating the flexible plasticized polyvinyl chloride film to the substrate, the improvement for enhancing adhesion and resistance to plasticizer migration from the flexible plasticized polyvinyl chloride film which comprises:

utilizing a water based, acrylic emulsion adhesive which incorporates a copolymer comprising polymerized units of C_1-12 alkyl acrylates or C_1-12 alkyl methacrylates and polymerized units of a vinyl C_8-13 ester of a neo-acid obtained from a feedstock of propylene oligomers.

2. The process of claim 1 wherein the copolymer has a T_g of from −

20 to −

50°

C.

3. The process of claim 2 wherein the vinyl ester is represented by the chemical formula:

4. The process of claim 2 wherein the copolymer is comprised of polymerized units of monomers (a) through (c) in the weight percentages of the total copolymer as set forth:

(a) 15-30 wt % of a vinyl ester of a neo-acid;

(b) 30-80 wt % of a C_1-12 alkyl acrylate or methacrylate, and

(c) an alpha, beta-ethylenically unsaturated monocarboxylic acid in an amount up to 10 wt %.

5. The process of claim 2 wherein the copolymer comprises polymerized units of methyl methacylate.

6. The process of claim 5 wherein the copolymer further comprises polymerized units of butyl acrylate or 2-ethylhexyl acrylate.

7. The process of claim 6 wherein the copolymer further comprises polymerized units of hydroxypropyl acrylate.

8. The process of claim 6 wherein the copolymer further comprises polymerized units of acrylic or methacrylic acid.

9. The process of claim 4 wherein the copolymer consists essentially of polymerized units of a vinyl ester of a neo-acid, methyl methacrylate, a C_1-12 alkyl acrylate consisting essentially of 2-ethylhexyl acrylate or butyl acrylate, and acrylic or methacrylic acid.

10. In a laminate comprised of a flexible plasticized polyvinyl chloride and a substrate bonded together by means of a pressure sensitive, water based, acrylic emulsion adhesive, the improvement which comprises as said water based, acrylic emulsion adhesive, an adhesive which incorporates a copolymer comprised of polymerized units of the following monomers.

(a) 15-30 wt % of a vinyl ester of a neo-acid;

(b) 30-80 wt % of a C_1-12 alkyl ester of acrylic or methacrylic acid, and,

(c) an alpha, beta-ethylenically unsaturated monocarboxylic acid in an amount up to 10 wt %.

11. The laminate of claim 10 wherein the copolymer has a T_g of from −

20 to −

50°

C.

12. The laminate of claim 11 wherein the vinyl ester is represented by the chemical formula:

13. The laminate of claim 12 wherein the copolymer comprise polymerized units of methyl methacrylate.

14. The laminate of claim 13 wherein the C_1-12 alkyl ester of acrylic or methacrylic acid is selected from the group consisting of butyl acrylate and 2-ethylhexyl acrylate.

15. The laminate of claim 14 wherein the alpha, beta-ethylenically unsaturated monocarboxylic acid is acrylic or methacrylic acid.

16. The laminate of claim 15 wherein the water based, acrylic emulsion adhesive consists essentially of polymerized monomer units of:

(a) a vinyl ester of a neo-acid, (b) methyl methacrylate, butyl acrylate or 2-ethylhexyl acrylate, and (c) acrylic or methacrylic acid.