| abstract |
1398599 Carbonates GENERAL ELECTRIC CO 24 Aug 1972 [1 Nov 1971] 39554/72 Heading C2C [Also in Division C3] Polymers of a carbonate of a halogenated dihydric phenol containing from 2 to 10 repeating units of formula in which R<SP>1</SP> and R<SP>2</SP> are hydrogen, C 1-6 alkyl or phenyl, X<SP>1</SP> and X<SP>2</SP> are bromo or chloro and m and r are from 1 to 4 and terminated respectively with halogenated aromatic substituents of formulµ in which X<SP>3</SP> and X<SP>4</SP> are bromo or chloro and p and q are each from 1 to 5, which polymers have low volatility above 200 C. and a softening point of less than 300 C. are claimed per se. Reference is made to the preparation in Examples 1 and 2 of a carbonate of tetrabromobisphenol A chain stopped with tribromophenol, having a molecular weight of about 3600, a bromine content of 58% and melting at 230-260 C. |