Macromolecules of polycarboxybetaine poly(4-N,N-diallyl-N-methylammonio) butanoate: Synthesis and molecular characteristics

Publication date: Available online 19 June 2017
Source:Polymer
Author(s): N.V. Tsvetkov, A.A. Lezov, P.S. Vlasov, A.S. Gubarev, A.A. Lezova, E.V. Lebedeva, G.E. Polushina, N.S. Domnina
A series of water-soluble poly(carboxybetaines) (poly(4-(diallyl(methyl)ammonio)butanoates), poly(DAMAB)) was synthesized. Detailed studies of the solution properties of these poly(carboxybetaines) were performed using viscometry, static and dynamic light scattering, velocity sedimentation and flow birefringence. Molar masses, other molecular parameters and conformational characteristics of the macromolecules were determined in water and 1 MNaCl solutions. The Mark-Kuhn-Houwink and scaling equations were obtained for poly(DAMAB). It was established that 1 M NaCl solution is a thermodynamically good solvent for poly(DAMAB). In water, the conformation of poly(DAMAB) molecules is similar to that of a polymer coil under θ-conditions. The Kuhn segment length for poly(DAMAB) molecules was A=7nm in water and in 1 MNaCl solution. Data on the thermal stability of DAMAB and its polymer were obtained. Thorough consideration of contributions of optical effects of micro- and macroform into the observed flow birefringence in copolymer solutions allowed us to estimate optical characteristics of copolymer macromolecules. Optical anisotropy of polarizability of the monomer unit of the studied poly(DAMAB) was negative. This fact indicates that the main anisotropic groups are located along the longer axis of their optical polarizabilities at high angles to the direction of the polymer chain growth.

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