Dilute Solution Properties of Poly-(N-Lauryl Methacrylate)

摘要

Poly-(n-lauryl methacrylate) was prepared by the emulsion technique and fractionally precipitated by using benzene as the solvent and isopropanol as the precipitant to yield nine sharp fractions.nThe weight-average molecular weight dependence of the intrinsic viscosity [η], and the root mean square end-to-end distance in an ideal (poor) solvent (isopropyl acetate at 13°C) and in a nonideal (good) solvent (n-butyl acetate at 23°C) were established. The relationship between the osmotic second virial coefficient A2 and the weight-average molecular weight Mw in the nonideal solvent (n-butyl acetate at 23°C was also determined.nThe effect of the size of the pendent group on the degree of chain ex¬tension is evident in the following order of decreasing chain extension:nPLMA > PHMA> POMA > PBMA > PEMA > PMMA.nHuggins constant k' was calculated for poly-(n-lauryl methacrylate) in the ideal and nonideal solvent.nThe molecular expansion factor a and the Flory universal constant were calculated for poly-(n-lauryl methacrylate).