| 摘要 |
<p>The invention relates to a process for producing non-CFC resol foams of low density using perfluorinated ethers along with an HCFC or CFC blowing agent, and to foams produced by such a process. The process generally comprises: (a) forming a mixture by combining a resol resin with a blowing-agent blend comprising (i) at least one blowing agent selected from the group consisting of hydrogenated chlorofluorocarbons and hydrogenated fluorocarbons and (ii) at least one perfluoroether additive selected from the group consisting of perfluorinated ethers; (b) adding an acid catalyst to the mixture to initiate foaming and form a foam; and (c) curing the foam to form a cured foam that is essentially free of CFCs.</p> |
