Patent · US Expired

Process for the preparation of expandable polystyrene

US5591778A · kind A · utility

4Cited by

11References

1Claims

0Family size

Assignee

BASF SE

Inventors

Dietrich Scherzer · Neustadt, DE
Klaus Hahn · Lampertheim, DE
Anthony G. Schaefer · Huntsville, US
Bernhard Schmied · Bischofswerda, DE

Key dates

Filing date	Aug 14, 1995
Grant date	Jan 7, 1997
Priority date	—
Expiry date	Aug 14, 2015

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08J2325/04
WIPO fieldOther special machines
WIPO sectorMechanical engineering

Abstract

The invention relates to a process for the preparation of bead shaped, expandable polystyrene by the polymerization of styrene in an aqueous suspension in the presence of dimeric .alpha.-methylstyrene as a regulator and a C.sub.3 to C.sub.6 hydrocarbon as a blowing agent, whereby one first reports the content of saturated hydrocarbons, having a boiling point between 70.degree. and 170.degree. C., in the styrene and dimeric .alpha.-methylstyrene, and then enough saturated hydrocarbons, having a boiling point from 70.degree. to 170.degree. C., are added before, during or after the polymerization so that their total content in the suspension is from 0.1 to 0.8 weight percent, based on the styrene.

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