ÜBer den einfluß der lösungsmittel auf die struktur linearer makromoleküle. I

Abstract

ZUSAMMENFASSUNG:Es werden einige Methoden angegeben, nach denen der von ausgeschlossenen Volumeneffekten unbeeinfluate Tragheitsradius (R;>lI2 bestimmt werden kann. Die theoretische Forderung LIFSONS, da13 selbst dieser Tragheitsradius noch vom Losungsmittel abhangt und sich im allgemeinen vom Tragheitsradius am O-Punkt unterscheidet, kann an den Beispielen von Polymethylmethacrylat und Polystyrol bestatigt werden. Als Ursache fiir die Losungsmittelabhiingigkeit scheint die Wechselwirkung des Losungsmittels mit den Kettengliedern verantwortlich zu sein, die sich nach der Theorie von KOBATAKE und INA-GAKI im scheinbaren spezifischen Volumen Vxx aul3ert. SUMMARY:Several methods are given for the calculation of the radius of gyration (R;>lI2 which is independent from excluded volume effects. Experiments on polymethyl methacrylate and polystyrene confirmed the theoretical postulation of LIFSON that -this radius of gyration depends on the solvent and that it differs in general from the radius of gyration at the @-point. The solvent effect appears to be due to the interaction of the solvent with the chain links which is expressed by the apparent specific volume according to the theory of KOBATAKE and INAGAKI.

The unperturbed conformation and interaction parameters of polyvinylalcohol in aqueous solutions. Polydispersity effects

“…Higher values of C1 definitely overestimate a~. Combination of equations [6], [8] and [9] results in the BSF relation:…”

“…Generally the validity of [11] is limited to small expansion factors, as expected from the restriction on [8]. However, Stacy and Arnett (24) found also in good solvents correct values for K 0.…”

“…For the second parameter the linear expansion factor, a, (4, 5) the polymersolvent interaction parameter, X, (5) and the exponent a of the Mark-Houwink-Sakurada To obtain these parameters most common practice involves viscometry (1,(4)(5)(6) of dilute solutions of polymers as a function of molecular weight. The resulting intrinsic viscosity-molecular weight data can be plotted in several ways (1,(7)(8)(9)(10) to obtain pairs of the above characteristics, for instance K0 and 2". Of these plotting methods that of Burchard-Stockmayer-Fixman (8,9) (BSF) is most convenient.…”

“…The resulting intrinsic viscosity-molecular weight data can be plotted in several ways (1,(7)(8)(9)(10) to obtain pairs of the above characteristics, for instance K0 and 2". Of these plotting methods that of Burchard-Stockmayer-Fixman (8,9) (BSF) is most convenient. A derivation and discussion of the BSF equation will be given in order to revive the special form of the equation in the case of polydisperse polymers and to review its abilities and limitations.…”

Effects of Side-Chain on Conformational Characteristics of Poly(3,5-Dimethyl-Phenyl Acrylate) in Toluene at 40℃

“…To verify the value of K θ , ∞ a plot of   According to the Yoshizaki-Nitta-Yamakawa theory [23], the hydrodynamic interaction depends on the reduced bead diameter d br which, in the range 0.3 ≤ d br ≤ 0.8, is related to the A 0 parameter by [33] which is the value of K 0 , ∞ of Equation (26B). Table 4 shows the characteristic parameters of 35PDMPA.…”