Conversion of cyclic polycarbonate oligomers to linear polycarbonates initiated by phosphine-disulfide product or precursor thereof
AssigneeGeneral Electric Company
InventorsHerman O. Krabbenhoft, Daniel J. Brunelle
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Abstract
Cyclic polycarbonate oligomers are polymerized to linear polycarbonates by the action of a salt prepared by the reaction of a triarylphosphine or triaryl phosphite with an organic disulfide, preferably an aryl disulfide. The reactants which form the salt may be incorporated in the cyclic polycarbonate composition, and interreact when the composition is heated to form the active initiating species.
Claims20
A method for preparing a resinous composition which comprises contacting, at a temperature in the range of about 280.degree.-350.degree. C., at least one cyclic polycarbonate oligomer with an effective amount to initiate polymerization of an initiator precursor system comprising (A) at least one organic disulfide, (B) at least one triarylphosphine or triaryl phosphite which is capable of reaction with reagent A to form a salt, the molar ratio of reagent A to reagent B being in the range of about 1-5:1, and any reaction products of reagents A and B.
A method for preparing a resinous composition which comprises contacting, at a temperature in the range of about 280.degree.-350.degree. C., at least one triaryl- or triaryloxythioorganophosphonium thiophenoxide of the formula
- [A.sup.3 (O).sub.y ].sub.3 P.sup..sym. --SR.sup.2.crclbar. S--R.sup.2, (III)
- wherein R.sup.2 is an organic radical, A.sup.3 is an unsubstituted or substituted aryl group and y is 0 or 1.
A polymerizable composition comprising cyclic polycarbonate oligomers comprising structural units of the formula ##STR3## wherein at least about 60% of the total number R.sup.1 values are divalent aromatic organic radicals, the balance thereof being aliphatic, alicyclic or aromatic organic radicals;
- and an initiator system comprising (A) at least one organic disulfide, (B) at least one triarylphosphine or triaryl phosphite which is capable of reaction with reagent A to form a salt, the molar ratio of reagent A to reagent B being in the range of about 1-5:1, and any reaction products of reagents A and B.
A polymerizable composition comprising cyclic polycarbonate oligomers comprising structural units of the formula ##STR5## wherein at least about 60% of the total number of R.sup.1 values are divalent aromatic organic radicals, the balance thereof being aliphatic, alicyclic or aromatic organic radicals;
- and at least one triaryl- or triaryloxythioorganophosphonium thiophenoxide of the formula
- [A.sup.3 (O).sub.y ].sub.3 P.sup..sym. --SR.sup.2.crclbar. S--R.sup.2, (III)
- wherein R.sup.2 is an organic radical, A.sup.3 is an unsubstituted or substituted aryl group and y is 0 or 1.
Dependencies are inferred from the claim text.