Title:
PRODUCTION OF EXPANDABLE VINYL RESIN PARTICLE
Document Type and Number:
Japanese Patent JP3125418
Kind Code:
B2
Abstract:
PURPOSE: To obtain expandable vinyl resin particles freed from flat particles and having a narrow particle diameter distribution.
CONSTITUTION: The title process comprises suspension-polymerizing a vinyl monomer in the presence of a difficultly soluble phosphate and an anionic surfactant. A water-soluble sulfite or its precursor is added to the reaction system before the polymerization is started or before the conversion reaches 30wt.%. The difficultly soluble phosphate is added to the system at least once while the conversion is between 20-60wt.%, and hydrogen peroxide is added to the system while the conversion is between 50-70wt.% after the addition of the phosphate. The particles are impregnated with a blowing agent during or after the polymerization.
Inventors:
Terumasa Honda
Yoshiyuki Kato
Tetsuo Kiman
Yoshiyuki Kato
Tetsuo Kiman
Application Number:
JP6337992A
Publication Date:
January 15, 2001
Filing Date:
March 19, 1992
Export Citation:
Assignee:
Hitachi Chemical Co., Ltd.
International Classes:
C08F2/18; C08F2/44; C08F12/08; C08F212/00; C08F212/08; C08J3/12; C08J9/16; (IPC1-7): C08F2/18; C08F12/08; C08J9/16
Domestic Patent References:
| JP59202202A | ||||
| JP3258806A |
Attorney, Agent or Firm:
Kunihiko Wakabayashi