Patent · US Expired

Sequential emulsion polymerization process

US4325856A · kind A · utility

93Cited by
23References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 2, 1980
Grant dateApr 20, 1982
Priority date
Expiry dateJan 2, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31906
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Aqueous copolymer latexes comprising colloidally dispersed, substantially spheroidal copolymer particles having a predominantly hydrophobic core portion and having a relatively hydrophilic polymeric portion which is preferentially oriented toward the outer surface thereof (e.g., a relatively hydrophilic shell portion) are prepared by (a) first emulsion polymerizing an initial monomer charge to form a first aqueous latex of a substantially linear, relatively hydrophilic polymer and (b) thereafter emulsion polymerizing a major proportion (e.g., from about 50 to about 95 parts by weight) of a second (and relatively more hydrophobic) monomer charge in the presence of a minor proportion (e.g., from about 5 to about 50 parts by weight on a polymer solids basis) of said first, relatively hydrophilic polymer latex.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.