Claims
- 1. A branched polycarbonate comprising units incorporated from a branching agent represented by the following general formula (I) ##STR8## wherein R.sup.1, R.sup.2 and R.sup.3 are each a hydrogen, an alkyl group having 1 to 5 carbon atoms or a halogen, and m, n and p are each an integer of 0 to 4,
- and wherein said branched polycarbonate contains at most 1.0 ppm of residual sulfur as an impurity derived from said branching agent, and wherein said branched polycarbonate is prepared by an interfacial method.
- 2. A branched polycarbonate comprising units resulting from a branching agent represented by the following general formula (I) ##STR9## wherein R.sup.1, R.sup.2 and R.sup.3 are each a hydrogen, an alkyl group having 1 to 5 carbon atoms or a halogen, and m, n and p are each an integer of 0 to 4,
- and wherein said branched polycarbonate contains at most 2.0 ppm of residual sulfur as an impurity derived from said branching agent, and wherein said branched polycarbonate is prepared by a melting method.
- 3. The branched polycarbonate according to claim 1 wherein the branching agent represented by the general formula (I) is a compound selected from the group consisting of 1,1,1-tris(4-hydroxyphenyl)ethane, 1,1,1-tris(4-hydroxy-3-methylphenyl)ethane, 1,1,1-tris(4-hydroxy-3,5-dimethylphenyl)ethane, 1,1,1-tris (3-chloro-4-hydroxyphenyl)ethane, 1,1,1-tris (3,5-dichloro-4-hydroxyphenyl)ethane, 1,1,1-tris (3-bromo-4-hydroxyphenyl)ethane, 1,1,1-tris (3,5-dibromo-4-hydroxyphenyl)ethane, tris (4-hydroxyphenyl)methane, tris(4-hydroxy-3-methylphenyl)methane, tris(4-hydroxy-3,5-dimethylphenyl)methane, tris(3-chloro-4-hydroxyphenyl)methane, tris(3,5-dichloro-4-hydroxyphenyl)methane, and tris(3-bromo-4-hydroxyphenyl)methane, and tris(3,5-dibromo-4hydroxyphenyl)methane.
- 4. The branched polycarbonate according to claim 1, wherein a branching agent is added in such an amount that the content of the unit of the branching agent in said branched polycarbonate finally obtained is 0.05 to 2.0% by mol, based on the amount in mol of the unit of the difunctional phenol.
- 5. The branched polycarbonate according to claim 1, wherein the branching agent is added in such an amount that the content of the unit of the branching agent in said branched polycarbonate finally obtained is 0.1 to 1.0% by mol based on the amount in mol of the unit of the difunctional phenol.
Priority Claims (1)
Number |
Date |
Country |
Kind |
5-249175 |
Oct 1993 |
JPX |
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Parent Case Info
This is a Division of application Ser. No. 08/318,259 filed on Oct. 5, 1994 now U.S. Pat. No. 5,473,046.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4415723 |
Hedges et al. |
Nov 1983 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
318259 |
Oct 1994 |
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