Patent · US Expired

Emulsion containing silicone particles of large size

US6235834A · kind A · utility

9Cited by
9References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 12, 1999
Grant dateMay 22, 2001
Priority date
Expiry dateJul 12, 2019

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G77/06
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Dialkyl sulfonic acid catalysts such as dialkyl benzene sulfonic acids, dialkyl naphthalene sulfonic acids, salts of dialkyl benzene sulfonic acids, and salts of dialkyl naphthalene sulfonic acids, are used to prepare emulsions containing particles of organopolysiloxanes having an average particle diameter in the emulsion of at least one micron (.mu.m) A silanol endblocked siloxane is used as an oligomer and has the structure ##STR1## wherein R1 to R6 are alkyl or aryl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and phenyl; and n has a value such as to provide oligomers with a viscosity ranging from about 20 to about 100,000 centipoise (mPa.multidot.s). The emulsified oligomer is then polymerized with the catalyst to form an organopolysiloxane polymer having a viscosity which can be as high as about 10 million centipoise (mPa.multidot.s).

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