Method for manufacturing expandable styrene type polymer particles
US5132330A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 18, 1991 |
| Grant date | Jul 21, 1992 |
| Priority date | — |
| Expiry date | Nov 18, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2325/00
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method for manufacturing expandable styrene type polymer particles is disclosed, which comprises the steps of adding a styrene type monomer to styrene type polymer seed particles suspended in an aqueous dispersing medium, continuously or intermittently to be polymerized while being absorbed thereby, and impregnating the resulting polymer particles with an easily volatile blowing agent to obtain expandable styrene type polymer particles, the improvement wherein styrene type polymer particles whose weight-average molecular weight (Mw.sub.1) is not more than 2/3 of the weight-average molecular weight (Mw.sub.2) of the resulting polymer particles are used as said styrene type polymer particles. The present invention provides expandable styrene type polymer particles excellent in moldability and foamed articles high in strength and fine in external appearance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.