Tetraphenol containing polycarbonates

Claim 2

A high molecular weight, branched polycarbonate substantially free of crosslinking which comprises a polycarbonate polymer containing residues of an aromatic dihydroxy compound, about 0.01 to about 1 mol percent of residues of 1,4-bis(4',4"-dihydroxy-triphenylmethyl)-benzene and about 0.1 to 8 mol percent of monohydric phenol, the mol percentages being based on the mols of the aromatic dihydroxy compound, said branched polycarbonate having a relative viscosity of from 1.2 to about 1.55 measured on a solution of 0.5 gram in 100 ml of methylene chloride at 20° C, an average molecular weight of between about 30,000 and about 100,000, measured by light diffusion and a melt viscosity of between 20,000 and about 300,000 poises at 280° C.

Claim 3

The high molecular weight, branched polycarbonate of claim 1 wherein the aromatic dihydroxy compound is selected from the group consisting of dimonohydroxy arylene alkanes and dimonohydroxy arylene sulphones.

Claim 4

The high molecular weight, branched polycarbonate of claim 2 wherein the dimonohydroxy arylene alkanes are 4,4'-dihydroxy-diphenylene alkanes.

Claim 5

The high molecular weight, branched polycarbonate of claim 3 wherein the 4,4'-dihydroxy-diphenylene alkanes are selected from the group consisting of: 2,2-(4,4'-dihydroxy-diphenylene)-propane; bis-(4-hydroxy-3,5-dichlorophenyl)-propane-2,2; bis-(4-hydroxy-3,5-dibromo-phenyl)-propane-2,2; bis-(4-hydroxy-3,5-dimethyl-phenyl)-propane-2,2 and 1,1-(4,4'-dihydroxy-diphenylene)-cyclohexane.

Claim 6

The high molecular weight, branched polycarbonate of claim 1 wherein the monohydric phenol is selected from the group consisting of phenol, lower alkyl phenols, aryl phenols, cycloaliphatic phenols and monophenol alkanes.

Claim 7

The process of making a high molecular weight, branched polycarbonate substantially free of crosslinking by adding about 0.01 to about 1 mol percent of 1,4-bis-(4',4"-dihydroxy-triphenylmethyl)-benzene and about 0.1 to about 8 mol percent of monohydric phenol to a solution or dispersion of organic dihydroxy compounds, the mol percentages being based on the mols of the organic dihydroxy compounds and reacting this mixture with phosgene or chlorocarbonic acid esters of the dihydroxy compounds to produce branched polycarbonate having a relative viscosity of from 1.2 to about 1.55 measured on a solution of 0.5 gram in 100 ml of methylene chloride at 20° C, an average molecular weight of between about 30,000 and about 100,000 measured by light diffusion and a melt viscosity of between 20,000 and about 300,000 poises at 280° C.

Claim 8

The process of making a high molecular weight, branched polycarbonate substantially free of crosslinking by adding about 0.01 to about 1 mol percent of 1,4-bis-(4',4"-dihydroxy-triphenylmethyl)-benzene and about 0.1 to about 8 mol percent of monohydric phenol to a solution or dispersion of organic dihydroxy compounds, the mol percentages being based on the mols of the organic dihydroxy compounds and reacting this mixture with phosgene or chlorocarbonic acid esters of the dihydroxy compounds to produce branched polycarbonate having a relative viscosity of from 1.2 to about 1.55 measured on a solution of 0.5 gram in 100 ml of methylene chloride at 20° C, an average molecular weight of between about 30,000 and about 100,000 measured by light diffusion and a melt viscosity of between 20,000 and about 300,000 poises at 280° C.

Claim 9

The product of the process of claim 6.

Claim 10

In a process for the production of aromatic polycarbonates by the reaction of di-(monohydroxyaryl)-alkanes with phosgene or the chlorocarbonic acid esters of di-(monohydroxyaryl)-alkanes in a two-phase mixture, the improvement wherein about 0.05 to 0.5 mol percent of 1,4-bis-(4',4"-dihydroxytriphenyl-methyl)-benzene and 0.1 to 8 mol percent of monohydric phenols, both based on the mols of said di-(monohydroxyaryl)-alkanes, are added to said mixture whereby a branched polycarbonate having a relative viscosity of from 1.2 to about 1.55 measured on a solution of 0.5 grams in 100 ml of methylene chloride at 20° C, an average molecular weight of between about 30,000 and about 100,000 measured by light diffusion and a melt viscosity of between 20,000 and 300,000 poises at 280° C, is formed.

Claim 11

In a process for the production of aromatic polycarbonates by the reaction of di-(monohydroxyaryl)-alkanes with phosgene or the chlorocarbonic acid esters of di-(monohydroxyaryl)-alkanes in a two-phase mixture, the improvement wherein about 0.05 to 0.5 mol percent of 1,4-bis-(4',4"-dihydroxytriphenyl-methyl)-benzene and 0.1 to 8 mol percent of monohydric phenols, both based on the mols of said di-(monohydroxyaryl)-alkanes, are added to said mixture whereby a branched polycarbonate having a relative viscosity of from 1.2 to about 1.55 measured on a solution of 0.5 grams in 100 ml of methylene chloride at 20° C, an average molecular weight of between about 30,000 and about 100,000 measured by light diffusion and a melt viscosity of between 20,000 and 300,000 poises at 280° C, is formed.

Claim 12

The product of the process of claim 8.