|
|
ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
|
Stability of polycarbonate solutions
G. Glöckner
Tech. Univ., Dresden, Germany.
Abstract: Polycarbonates U (I) are prepd. by transesterification of bis(hydroxyphenyl) alkanes (II) with (PhO)2CO; polycarbonates G (III) are prepd. in a two-phase solvent system by reaction of II and COCl2 (Schnell, CA 52, 8089i). Solns. of I in mixts. of purified CHCl3 or (CH2Cl)2 and MeOH exhibit a very slight increase of viscosity in 30 days. Solns. of III, under the same conditions, exhibit a gradual decrease of viscosity which tends asymptotically to values equal to about 85% of the initial values (contrary to Yakubovich, et at., CA 57, 1043h), and which depends on the amt. of MeOH in the mixt.; alcoholysis of the polymer is the most probable cause of this decrease. The resistance of I to alcoholysis is probably due to its higher degree of branching, and the slight increase of viscosity to some aggregation (Kuhn and Moser, CA 55, 18272c).
Full paper in Portable Document Format: 176a419.pdf (in Slovak)
Chemical Papers 17 (6) 419–424 (1963)
|