Conformational analysis of poly(2-hydroxyethyl methacrylate)

Abstract

The poly(2-hydroxyethyl methacrylate) (PHEMA) is a disubstituted vinyl chain in which the disubstitutents $CO_2CH_2CH_2OH$ and $CH_3$ differ in size and shape. In order to clarify the character of various interactions in the PHEMA chain, we carry out the conformational energy calculations for the stereoregular isotactic and syndiotactic oligomers of the PHEMA by the conventional empirical method. From the calculations, we obtain the energy contour map, various conformational minima states and statistical weights may be estimated. From the conformational energies and statistical weights, the characteristic ratio, $C_{\infty} = (<r^2>0/nl^2)_{\infty}$ for the isotactic and syndiotactic chains have been calculated. The calculated $C_{\infty}$ for the isotactic chain and syndiotactic chain are 12.4 and 7.8, respectively. The calculated valves have been compared with the experimental values obtained under ethanol solvent. The $C^{\infty}$ for the isotactic chain reproduce approximately the experimental values.