Patent · US Expired

Urea-modified isocyanurates

US5288768A · kind A · utility

1Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1992
Grant dateFeb 22, 1994
Priority date
Expiry dateDec 21, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S521/902
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Rigid urea-modified polyisocyanurate foams with improved dimensional stability and flame retardancy have densities of 0.5-20 p.c.f., a limiting oxygen index greater than 22 and dimensional changes at 100% R.H. and 70.degree. C. of less than 2% in any linear dimension and a method of making same. The method comprises reacting an organic polyisocyanate, a blowing agent and an N,N'-dialkyl aromatic diamine in the presence of a trimerization catalyst and, if water is used as the blowing agent, a blowing catalyst, wherein the N,N'-dialkyl aromatic diamine and an amine produced by water, if used, constitute the sole sources of active hydrogen.

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