| abstract |
Disclosed is the polyurethane composite blowing agent that contains dialkyl carbonate and alcohol amine salt, and this composite blowing agent mainly comprises following components: component (FA) first blowing agent, this first blowing agent is: ( fa1) lower boiling physical blowing agents, (fa2) amine carbonates (AAC) and/or (fa3) mixtures of amine carbonates (MAA); wherein component (fa1) lower boiling physical blowing agents Be selected from one or more of cyclopentane, HCFC-141b, HFC-245fa, HFC-365mfc, LBA (one chlorotrifluoropropene), hexafluorobutene and trans-dichloroethylene; and component (FB) bis (C 1 -C 2 alkyl) carbonate as the second blowing agent, wherein the mass ratio of component (FA) and component (FB) in composite blowing agent is 0.2-6: 1. The composite blowing agent can eliminate the local foam core burning phenomenon in the existing foam material preparation method. In addition, the composite blowing agent can also contain (FC) fluorocarbons (such as R134a, R125, R152a, R32, R227ea, etc.) with a boiling point of -70°C to 0°C to promote polyurethane nucleation and improve foam insulation performance. |