Polycarbonate copolymer containing oxaspiroundecane group and production process therefor

A process for producing a polycarbonate polymer, which comprises melt polycondensing 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro›5.5!undecane represented by the following formula (III) ##STR47## a bisphenol represented by the formula (IV) ##STR48## wherein R.sup.1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms;

• R.sup.2 and R.sup.3 are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms;
• A is a single bond or forms, together with the oxygen atom adjacent to A, a group --O--(C.sub.2-4 alkylene group)--O--;
• X is selected from the group consisting of a group ##STR49## in which R.sup.4 and R.sup.5 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms, a group ##STR50## in which R.sup.6, R.sup.7 and R.sup.8 are the same or different and each a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and n is 0 or 1,
• a group ##STR51## --O--, --S--, --SO--, --SO.sub.2 --, a fluroidene group and a group ##STR52## and a diarylcarbonate represented by the following formula (V) ##STR53## wherein Ar.sup.1 and Ar.sup.2 may be the same or different, and selected from phenyl and naphthyl, and may be substituted by at least one member selected from the group consisting of a chlorine atom, an alkyl group having 1 to 6 carbon atoms, a methoxycarbonyl group and an ethoxycarbonyl group, and
• wherein 5 to 95 mol % of the compound of the above formula (III) is added to 95 to 5 mol % of the compound of the above formula (IV), and 1.0 to 1.3 mole of the compound of the above formula (V), based on 1 mole of the total of the compound of the above formula (III) and the compound of the above formula (IV), so as to produce a polycarbonate having a reduced viscosity of at least 0.3 dl/g.