Process for preparing the polycarbonate of 2,2,4,4-tetramethyl-1,3-cyclobutanediol
AssigneeEastman Chemical Company
InventorsWilliam R. Darnell, John C. Morris
Life of this patent
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Abstract
The invention relates to a method for preparing a polycarbonate, by mixing a compound having the structure I: ##STR1## and a basic catalyst, and heating the mixture to produce the polycarbonate. The invention also relates to poly(2,2,4,4-tetramethyl-1,3-cyclobutylene carbonate) with an inherent viscosity of at least 0.7 dL/g. The invention also relates to an article made from the polycarbonate and a blend containing poly(2,2,4,4-tetramethyl-1,3-cyclobutylene carbonate).
Claims35
A method for preparing a polycarbonate, comprising:
- (a) admixing
- (i) a compound having the structure I:
- ##STR4## and (ii) a basic catalyst, and
- (b) heating the admixture of step (a) to produce the polycarbonate having an inherent viscosity of at least 0.4 dL/g, as determined in 60/40 wt/wt phenol/tetrachloroethane solution at 25.degree. C.
A process of preparing poly(2,2,4,4-tetramethyl-1,3-cyclobutylene carbonate), comprising condensing carbonic acid 3-methoxycarbonyloxy-2,2,4,4-tetramethyl-cyclobutyl ester methyl ester in the presence of a catalyst selected from the group consisting of alkali metals, alkoxides of alkali metals, carboxylates of alkali metals, and mixtures thereof under polycondensation conditions of temperature and pressure.
A polycarbonate, comprising poly(2,2,4,4-tetramethyl-1,3-cyclobutylene carbonate) with an inherent viscosity of at least 0.7 dL/g, as determined in 60/40 wt/wt phenol/tetrachlorethane solution at 25.degree. C.
Dependencies are inferred from the claim text.