Halogen-free blowing agents that include cycloaliphatic hydrocarbons and are suitable for isocyanate-based polymeric foams
US5336696A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 10, 1993 |
| Grant date | Aug 9, 1994 |
| Priority date | — |
| Expiry date | Dec 10, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2375/04
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A halogen-free blowing agent is used to produce isocyanate-based polymeric foams. The blowing agent is an organic liquid which is free from halogens and contains a positive binary azeotrope having a minimum boiling temperature in the range of about 15.degree. C. to about 80.degree. C. at normal atmospheric pressure. Particularly preferred is a binary azeotrope of an alicyclic hydrocarbon such as cyclopentane or cyclohexane and methyl formate. The halogen-free blowing agents contemplated herein provide the following advantages: no ozone depletion potential, no global warming potential, direct replacement in foam formulations for trichloromonofluoromethane (CFC-11), relatively higher blowing action, relatively lower foam density, relatively lower thermal conductivity, better compatibility, and relatively lower materials cost.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.