Rigid polyurethane foam made with a hydrocarbon blowing agent and 1,1,1,4,4,4-hexafluorobut-2-ene

Patent metadata

Field	Value
Publication number	US-12570786-B2
Application number	US-202017639666-A
Country	US
Kind code	B2
Filing date	Aug 14, 2020
Priority date	Sep 2, 2019
Publication date	Mar 10, 2026
Grant date	Mar 10, 2026

Abstract

Polyurethane thermal insulating foam is made in the presence of a small amount of cis- and/or trans-1,1,1,4,4,4-hexafluorobut-2-ene and a hydrocarbon blowing agent. Very low lambda values are obtained.

First claim

The invention claimed is:

1 . A method of making a polyurethane foam, comprising forming a reaction system and curing the reaction system to produce the polyurethane foam, wherein the reaction system comprises:
a) at least one polyisocyanate; b) at least one polyol; c) at least one urethane catalyst; d) at least one foam-stabilizing surfactant; e) 0 to 3 weight-percent water, based on the combined weights of components b), c), d) and e); f) 2 to 4 parts by weight, per 100 parts by weight of components b), c), d) and e), of 1,1,1,4,4,4-hexaflurobut-2-ene; and g) 12 to 20 parts by weight, per 100 parts by weight of components b), c), d) and e), of one or more hydrocarbons having 4 to 6 carbon atoms, wherein the reaction system contains from 5 weight percent to 25 weight percent of an alkoxylated o-toluene diamine polyol, based on the combined weights of components b), c), d) and e), and wherein the reaction system is introduced into a cavity and cured in the cavity, and a pressure of 700 to 950 millibars absolute is maintained in the cavity as the reaction system is introduced into the cavity.

2 . A polyurethane foam made in the method of claim 1 .

3 . The foam of claim 2 which exhibits a lambda value of at most 18.5 mw/m-° K as measured according to EN 12667 at an average plate temperature of 10° C.

4 . The foam of claim 2 which exhibits a lambda value of at most 18.25 mw/m-° K as measured according to EN 12667 at an average plate temperature of 10° C.

5 . The foam of claim 2 which has a density of 28 to 40 kg/m 3 as measured according to ASTM 1622-88.

6 . A method of manufacturing a thermally insulated cabinet, comprising
A) positioning an outer shell member and an inner liner member so as to define a cavity therebetween; B) introducing the reaction system into the cavity; and C) curing the reaction system such that it expands and reacts to produce a polyurethane foam that fills the cavity and adheres to the outer shell member and to the inner liner member, wherein the reaction system comprises: a) at least one polyisocyanate; b) at least one polyol; c) at least one urethane catalyst; d) at least one foam-stabilizing surfactant; e) 0 to 3 weight-percent water, based on the combined weights of components b), c), d) and e); f) 2 to 4 parts by weight, per 100 parts by weight of components b), c), d) and e), of 1,1,1,4,4,4-hexaflurobut-2-ene; and g) 12 to 20 parts by weight, per 100 parts by weight of components b), c), d) and e), of one or more hydrocarbons having 4 to 6 carbon atoms, wherein the reaction system contains from 5 weight percent to 30 weight percent of an alkoxylated o-toluene diamine polyol, based on the combined weights of components b), c), d) and e), and a subatmospheric pressure of 700 to 950 millibars absolute is maintained in the cavity during at least step B).

Assignees

• Dow Global Technologies Llc

Inventors

• Kramer Hans
• Mosciatti Thomas

Classifications

• C08J2375/04

  Polyurethanes · CPC title

• C08J2205/10

  Rigid foams · CPC title

• C08J2203/182

  of physical blowing agents, e.g. acetone and butane · CPC title

• C08J2203/162

  Halogenated unsaturated hydrocarbons, e.g. H2C=CF2 · CPC title

• C08J2203/142

  Halogenated saturated hydrocarbons, e.g. H3C-CF3 · CPC title