Patent · US Active

Polystyrene melt extrusion process

US9517579B2 · kind B2 · utility

2Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 22, 2011
Grant dateDec 13, 2016
Priority date
Expiry dateJun 8, 2033

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08J2453/02
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Extruded polystyrene foams are made with an added brominated styrene-butadiene polymer as a flame retardant. The blowing agent is a mixture of carbon dioxide, ethanol and water, which may also contain a C4-C5 hydrocarbon. The blowing agent mixture overcomes a tendency of the brominated styrene-butadiene to form very small cells. This allows the foam to expand fully to form good quality, low density extruded foam.

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