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Relationships between limiting viscosity number and molecular weight are reported for the systems poly(viny1 acetate) in acetone a t 6 and 3OoC, in chloroform at 6OC, and in the @-solvent methanol a t 6OC, in the molecular weight range from 3.5.103 to 1.5.106 using 24 narrow distribution fractions. Plots of [T] us. M on a double logarithmic graph indicate that K and v in the KUHN-HOUWINK-SAKURADA equation are not constant for the good solvent systems. Neither the FLORY-FOX-SCHAEFGEN plot nor the STOCKMAYER-FIXMAN plot gives straight lines. A new empirical relationship is proposed for [q] us. M. ZUSAMMENFASSUNG: Die Beziehung zwischen der Viskositatszahl und dem Molekulargewicht wurde fur Polyvinylacetat an Hand von 24 Fraktionen mit enger Verteilung im Molekulargewichtsbereich von 3,5.103 bis 1,5.106 neu untersucht. Als Losungsmittel dienten Aceton bei 6 und 3OoC, Chloroform bei 6OC und das @-Losungsmittel Methanol bei 6OC. Die doppeltlogarithmische Auftragung von [q] gegen das Molekulargewicht zeigt, da13 die Werte fiir K und v in der KUHN-HOUWINK-SAKURADA-Gleichung bei den guten Losungsmitteln nicht konstant sind ; weder die FLORY-FOX-SCHAEFGEN-noch die STOCKMAYER-FIXMAN-A~~tragung ergeben Geraden. Eine neue empirische [?I-M-Beziehung wird angegeben.

Distribution of diethylene glycol (DEG) component in the fine texture of polyester fibers has been investigated by measuring the concentrations of DEG in the decomposed and the residual portions obtained by heterogeneous aminolysis of the fibers using monomethylamine. The result shows that the region having higher DEG content decomposes more easily in both fibers of polyethylene terephthalate (PET) and copolyester having DEG as one glycol component.The tendency becomes remarkable as the temperature of the heat treatment of the fibers prior to the aminolysis is increased. From the analyses of the data obtained by gel permeation chroma tography of the residual portion and of the crystallinity by X-ray and infrared spectroscopy, it is shown that aminolysis proceeds successively from the amorphous region where amine can easily pass into. Even in the heat treatment of PET fibers, crystallization occurs by squeezing the DEG rich portion out to the amorphous region, resulting in the increase of DEG concentration in the amorphous region. The change in the dyeing behavior of fibers by heat treatment can be reasonably explained by taking account of the quality change of the amorphous region due to the increase of DEG.