Polyolefin substrate coated with acrylic-type normally tacky and pressure-sensitive adhesive and a method of making same

• US 4,563,388 A
• Filed: 02/27/1984
• Issued: 01/07/1986
• Est. Priority Date: 03/28/1983
• Status: Expired due to Term

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Simpson, J. Thomas, Bonk, Thomas J.
• Primary Examiner(s): Buffalow, Edith
• Application Number:
  US06/583,896
• Time in Patent Office: 680 Days
• Field of Search: 525/240, 428/355, 428/40, 428/317.1, 428/317.3, 428/317.5, 428/317.7, 428/304.4, 427/35, 427/42, 427/54.1, 427/44, 427/43.1, 427/412.3, 427/208.4, 427/208.8
• US Class Current: 428/304.4
• CPC Class Codes: C08F 255/00 Macromolecular compounds obtained by polymerising monomers on to polymers of hydrocarbons as defined in group C08F10/00
• CPC Class Codes: C08J 2323/02 not modified by chemical after treatment
• CPC Class Codes: C08J 7/16 with polymerisable compounds
• CPC Class Codes: C09J 7/50 characterised by a primer layer between the carrier and the adhesive
• CPC Class Codes: Y10T 428/1462 Polymer derived from material having at least one acrylic or alkacrylic group or the nitrile or amide derivative thereof [e.g., acrylamide, acrylate ester, etc.]
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/249983 As outermost component
• CPC Class Codes: Y10T 428/249985 Composition of adhesive or bonding component specified
• CPC Class Codes: Y10T 428/287 including epoxy group or epoxy polymer
• CPC Class Codes: Y10T 428/2874 including aldehyde or ketone condensation polymer [e.g., urea formaldehyde polymer, melamine formaldehyde polymer, etc.]

Abstract

Acrylic-type normally tacky and pressure-sensitive adhesives are firmly bonded to polyolefin substrates that have been primed by coating with a monomer composition and subjecting the coated substrate to actinic radiation to effect graft-polymerization.

Claims

1. A normally tacky and pressure-sensitive adhesive-coated product comprising:

(a) a polyolefin substrate,

(b) A monomer composition graft-polymerized to at least a portion of said substrate by ionizing radiation, said monomer composition having at least one monomer selected from the group consisting of acrylic acid, methacrylic acid and esters thereof;

acrylamide;

methacrylamide;

sterically non-hindered tertiary alkyl acrylamides and methacrylamides;

secondary alkyl acrylamides and methacrylamides having three or less carbon atoms in the alkyl group; and

N-vinyl pyrrolidone, and

(c) firmly adherently bonded to the graft-polymerized monomer an acrylic type normally tacky and pressure-sensitive adhesive.

2. The product of claim 1 wherein the polyolefin substrate is a layer of polyallomer.

3. The product of claim 1 wherein the esters of acrylic acid and methacrylic acid are selected from hydroxyethyl methacrylate, iso-butyl methacrylate, allyl methacrylate, cyclohexyl methacrylate, iso-decyl methacrylate, hexanediol dimethacrylate, hexanediol diacrylate, n-hexyl methacrylate, β

-carboxyethyl acrylate, thiodiethylene glycol diacrylate, glycidyl methacrylate, 2,3-dibromopropyl acrylate, and diethylaminoethyl acrylate.

4. The product of claim 1 wherein the sterically non-hindered tertiary alkyl acrylamides are selected from N,N-dimethyl acrylamide, N,N-diethyl acrylamide, N,N-dipropyl acrylamide, N-ethyl-N-n-butyl acrylamide, N,N-dimethyl methacrylamide, N,N-diethyl methacrylamide, and N,N-dipropyl methacrylamide.

5. The product of claim 1 wherein the secondary alkyl acrylamides are selected from N-methyl acrylamide, N-ethyl acrylamide, and N-n-propyl acrylamide.

6. The product of claim 1 wherein the monomer composition further comprises a minor effective amount of a crosslinking agent.

7. The product of claim 6 wherein the crosslinking agent is selected from polyethylene glycol diacrylate, pentaerythritol tetracrylate, tetraethylene glycol dimethacrylate, trimethylol propane triacrylate, trimethylol propane trimethacrylate, allyl methacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, thiodiethylene glycol diacrylate, and triallyl cyanurate.

8. The product of claim 1 wherein the acrylic type adhesive is an iso-octyl acrylate:

acrylic acid copolymer.

9. The product of claim 1 wherein a stratum of foam is bonded to the exposed surface of the acrylic adhesive.

10. The product of claim 9 wherein a second layer of normally tacky and pressure-sensitive adhesive is bonded to the exposed surface of the foam.

11. A normally tacky, pressure-sensitive adhesive-coated polyolefin substrate, having adhesive firmly adhered to said substrate, even at elevated temperatures, prepared according to a process comprising the steps of:

(a) treating the surface of said substrate to enable a polar liquid to wet said surface,

(b) coating on said substrate a monomer composition containing a monomer selected from the group consisting of acrylic acid, methacrylic acid and esters thereof;

acrylamide;

methacrylamide;

sterically non-hindered tertiary alkyl acrylamides and methacrylamides;

secondary alkyl acrylamides and methacrylamides having three or less carbon atoms in the alkyl group; and

N-vinyl pyrrolidone,

(c) irradiating the coated substrate with ionizing radiation to graft-polymerize said monomer to the treated substrate, and

(d) applying a layer of acrylic-type pressure-sensitive adhesive over the graft-polymerized surface.