Patent · US Expired

Bead size distribution in the suspension polymerization of vinyl aromatic monomers

US4169828A · kind A · utility

10Cited by
8References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 27, 1977
Grant dateOct 2, 1979
Priority date
Expiry dateDec 27, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S526/91
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

The production of polymer beads by a suspension polymerization process in which a vinyl aromatic monomer having a free-radical generating catalyst dissolved therein is suspended in an aqueous medium with the aid of from 0.1 to 2.0 percent by weight, based on monomer, of a finely divided phosphate suspending agent in the presence of a modifier and heated to cause the monomer to polymerize into polymer beads is improved by the addition to the suspension of at least about 0.01 percent by weight based on monomer of an adjunct modifier, such as certain aminoalkanecarboxylic acids and N-substituted derivatives thereof. The process of the invention is especially applicable in the preparation of large polymer beads.

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