Process for preparing pressure sensitive adhesives
US4725639A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 9, 1983 |
| Grant date | Feb 16, 1988 |
| Priority date | — |
| Expiry date | Nov 9, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09J2301/302
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
In a process for preparing a pressure sensitive adhesive emulsion containing a polymer having a Tg of -10.degree. C. or below which comprises polymerizing in an aqueous emulsion (a) an alkyl acrylate or vinyl ester, (b) an olefinically unsaturated carboxylic acid and (c) a polyolefinically unsaturated monomer for enhancing cohesive strength of the polymer, the method for enhancing the shear resistance of the pressure sensitive adhesive polymer which comprises PA0 (1) forming an aqueous suspension reaction mixture comprising a stabilizing agent and at least a portion of the alkyl acrylate or vinyl ester, PA0 (2) initiating the reaction mixture by the addition of a free radical source at a temperature from about 10.degree.-40.degree. C. and bringing the reaction mixture to a reaction temperature of from 45.degree.-85.degree. C. within a period of not more than 2 hours with the reaction temperature exceeding the initiation temperature by at least 15.degree. C., PA0 (3) adding the olefinically unsaturated carboxylic acid monomer and the polyolefinically unsaturated monomer at a substantially uniform rate such that the major portion of the carboxylic acid and polyolefinically unsaturate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.