Synthesis, solution properties and chain flexibility of poly(2,6-dimethylphenyl methacrylate)

The dilute solution properties of poly(2,6-dimethylphenyl methacrylate) (PDMP) in various solvents were studied by viscosity, size exclusion chromatography (s.e.c.) and osmotic pressure measurements. The Kuhn-Mark-Houwink-Sakurada (KMHS) relationships were established. The unperturbed dimensions <r²> ^{1 2}₀, the rigidity factor σ, the characteristic ratio C_∞, and the thermodynamic parameters were determined by using the Stockmayer-Fixman equation, from viscometric data in good and theta conditions in pure and mixed solvents. The results show that preferential adsorption of water in the mixture THF/water, should not play an important role in the determination of the conformational parameters in this system. In addition, the measured rigidity of PDMP can be explained assuming that this polymer behaves as a kinked-chain molecule. The conformational behaviour of this polymer is analysed in terms of the effect of the side chain structure in relation to poly(phenyl methacrylate) (PPh).