The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 22, 1979
Filed:
Feb. 01, 1977
Dusan C Prevorsek, Morristown, NJ (US);
Yali Kesten, Highland Park, NJ (US);
Allied Chemical Corporation, Morris Township, Morris County, NJ (US);
Abstract
Copolymers consisting of bisphenol-A ('BPA'), terephthalate ('TP'), and carbonate moieties in mol ratio from 2:0.8:1.2 to 2:1.3:0.7, which are melt processable in the sense of (a) showing no more than 10% change in viscosity number upon compression molding for 10 minutes at 320.degree. C. to form a plaque, (b) developing, in 2% (gm./ml.) DCM solution, a 'yellowness index' of no more than 10 as observed by ASTM Test No. D-1925, using a 2 cm. path length; which copolymers approximate in properties the alternating copolymer consisting of the above moieties, as indicated by their having viscosity numbers ('I.V.') in the range between 0.6 and 1.5 dl./gm. and T.sub.G of 170.degree. to 194.degree. C., with T.sub.G vs. I.V. relationship conforming to the formula, T.sub.G =192-(11.5/I.V.)+9 and with difference of (T.sub.G -HDT) of not over 15.degree. C.; having Izod impact resistance (ft.-lb. per inch of notch) at 25.degree. C. of at least 5; and being essentially free of pyridine and of anhydride linkages. The copolymers preferably have a mol ratio of BPA:TP:carbonate in the range from 2:0.9:1.1 to 2:1.2:0.8, viscosity number of 0.6-1 dl./gm., T.sub.G of at least 178.degree. C. by differential scanning calorimetry, heat distortion (or deflection) temperature of at least 170.degree. C., and Izod impact resistance at 25.degree. C. of at least 6 ft.-lb. per inch of notch. Process is disclosed of making such copolymer involving adding, to a solution of bisphenol-A, a solution of terephthaloyl chloride; reacting at 2:1 molar proportions of BPA:TPC in dichloromethane/pyridine; then phosgenating. The product is especially useful in glazing and transparent sheet applications requiring high impact resistance, high abrasion resistance and/or high solvent resistance.