Synthesis And Solution Characterization Of Modified Polyacrylamide

Acrylamide copolymers modified with acrylic acid(AA), methyl-acryloxyethyl-trimethyl ammonium chloride(DMC), 2-hydroxyethyl acrylate(HEA) or N,N'-methylene bisacrylamide (MBAA) were prepared by aqueous solution polymerization in this paper. The copolymer structures were determined by FT-IR spectroscopy. The heat properties of copolymers were determined by TG analysis. The composition of co-monomers in copolymers have been measured by element analysis. The effects of monomer.feed ratio on the intrinsic viscosities([?]) and Huggins constant(k_H) which were determined using an Ubbelohde viscometer, with the method of dilute extensional method, have been investigated in 1.0 mol·L^-1 NaCl solution. The results indicated that increasing the feed ratio of AA and DMC reduced the intrinsic viscosities of the copolymers, whereas increasing the feed ratio of HEA and MBAA raised the intrinsic viscosities of the copolymers.The effects of copolymer concentration and NaC1 concentration in aqueous solution, temperature and shear rate on the apparent viscosity of copolymers aqueous solution were also investigated. As a result, under the same copolymerization parameters, when the feed ratio of HEA is 6mo1%, the apparent viscosity is 2400mPa.S, about twice than that-of the copolymer without HEA, and the heat resistance of the copolymer was increased by 50%. When the feed ratio of MBAA is 0.6wt%, the apparent viscosity, is 3200mPa.S, about three times than that of the copolymer without MBAA, the heat resistance of the copolymer was increased by 50% as well.Acrylamide copolymers modified with a few amount of octadecyl acrylate(OA)(0.5～1.5mol%) have been prepared in N, N-Dimethyl formamide(DMF) at 70^C using benzoyl peroxide as initiator. The copolymer structure was determined by FT-IR spectroscopy; The copolymer composition was determined by Elemental analysis. The heat resistance property of copolymers was determined by TG analysis. The effects of temperature and NaC1 consentration on apparent viscosity of copolymers aqueous solution have been investigated. The apparent viscosity increases obviously with the increase of NaC1 consentration, meaning the good salt resistance of the copolymer. For PAM/OA(1.0) polymer, when SDS(sodium dodecyl sulfate) content is 0.5wt%, there is a evident cooperative phenomenon between SDS and polymer, and the apparent viscosity of PAM/OA(1.0) of 3wt% aqueous solution increased by 20 times up to 6000mPa.S at 30℃.