Series Of Relative Molecular Mass Pdmdaac Aqueous Solution The Nature Of A Preliminary Study

The aqueous solution properties of poly-dimethyldiallylammonium chloride (PDMDAAC) with different molecular weight(intrinsic viscosity) and narrow distribution were studied in this paper.Using Ubbelohde viscometer at(30.0±0.1)℃,the relationship between the reduced viscosity of PDMDAAC with intrinsic viscosity of 0.95,2.01 and 4.00dL·g^-1 and the concentration of inorganic salts in the solution of PDMDAAC,and the relationship between the reduced viscosity and the mass concentration of PDMDAAC were researched, respectively.Using GPC-MALLS at 25℃,the molecular weight distribution,root mean squared radius of gyration and unperturbed dimension of narrow distributed PDMDAAC with the intrinsic viscosity of 0.95,2.01 and 4.00dL·g^-1 in 0.50mol-L^-1 NaCl were obtained, respectively.The value of K,a of Mark-Houwink of PDMDAAC with the intrinsic viscosity ranging from 0.29dL·g^-1 to 3.74dL·g^-1 was investigated.The results showed that PDMDAAC demonstrated a tipycal polyelectrolyte effect with the mass concentration of PDMDAAC decreasing,the reduced viscosity increased in pure water.With the concentration of inorganic salts increasing,the reduced viscosity decreased and finally achieved to a constant value,the concentration of inorganic salt required when the reduced viscosity achieved to a constant value related to the intrinsic viscosity and the sort of inorganic salts.The structural morphology of PDMDAAC with 0.95 and 2.01dL·g^-1 in 0.50 mol·L^-1 NaCl solution was spherical shape,and for 4.00 dL·g^-1 is random coil.The value of K, a of Mark-Houwink of PDMDAAC with the intrinsic viscosity in the range of 0.29-3.74 dL·g^-1 was 7.37×10^-2 and 0.60,respectively.The viscosity behavior of PDMDAAC in aqueous solution was determined by the intrinsic viscosity of PDMDAAC,the concentration and anionic valence of inorganic salts. NaCl solution of 0.50 mol·L^-1 was a good solvent for PDMDAAC with 0.95 and 2.01dL·g^-1, and is a poor solvent for PDMDAAC of 4.00dL·g^-1.NaCl solution of 0.50mol·L^-1 could not satisfy the determination of high intrinsic viscosity product.