摘要 |
1,172,902. Non-inflammable phenolic resin foams. PLASTUGIL. 10 April, 1967 [18 April, 1966], No. 16369/67. Headings C3C and C3R. Phenolic foams of improved thermal stability and self-extinguishability are prepared by blowing phenolic resins, which have a polyhydroxy and/or polyamino derivative of a polychlorodiphenyl or of a polychloropolyphenylbenzene incorporated therein at the phenolaldehyde condensation stage. The said derivative may be present in a ratio of 5-50% by wt. of the phenolic resin. In the example, N,N<SP>1</SP>-bis- (2 - hydroxyethyl) diamino - octachlorodiphenyl is incorporated in a phenol-formaldehyde mixture before polymerization and the resulting resin is foamed by blowing with pentane and simultaneously hardening with conc. HCl. Other suitable derivatives for use in the invention include N,N<SP>1</SP>-bis-(2-hydroxyethyl) diaminododecachloroparaterphenyl, N,N<SP>1</SP> - bis - (hydroxy) diaminooctachlorodiphenyl, bis - (hydroxyethoxy) octachlorodiphenyl, octachlorodihydroxydiphenyl, N,N<SP>1</SP> - bis - (2 - aminoethyl) diaminooctachlorodiphenyl, bis - (2,2 - dihydroxymethyl - but. - 1 - oxy) octachlorodiphenyl and 4,4<SP>1 </SP>- bis - (diethylenetriamino)-hexachlorodiphenyl. |