反应详情

The polycarbonates may be branched by the incorporation of small quantities of polyhydroxy compounds, for example from 0.05 to 2.0 mole % (based on the bisphenols used). Polycarbonates of this type are described, for example, in German Offelengungsschrifts Nos. 1,570,533; 2,116,974; 2,113,347; in British Patent Nos. 885,442; 1,079,821 and in U.S. Pat. No. 3,544,514. Some of the polyhydroxy compounds which may be used are, for example, phloroglucinol, 4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptane, 1,3,5-tri-(4-hydroxyphenyl)-benzene, 1,1,1-tri-(4-hydroxyphenyl)-ethane, tri-(4-hydroxyphenyl)-phenyl methane, 2,2-bis-[4,4-(4,4'-dihydroxydiphenyl)-cyclohexyl]-propane, 2,4-bis-(4-hyroxyphenyl 4-isopropyl)-phenol, 2,6-bis-(2'-hydroxy-5-methylbenzyl)-4-methylphenol, 2,4-dihydroxybenzoic acid, 2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)-propane, 1,4-bis-(4',4"-dihydroxytriphenylmethyl)-benzene.