Mechanical and thermal properties of perfluoroalkyl ethyl methacrylate-methyl methacrylate statistical copolymers synthesized in supercritical carbon dioxide

CENGİZ U., Gengec N., Kaya N. U., Erbil H. Y., Sarac A. S.

JOURNAL OF FLUORINE CHEMISTRY, vol.132, no.5, pp.348-355, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 132 Issue: 5
  • Publication Date: 2011
  • Doi Number: 10.1016/j.jfluchem.2011.03.010
  • Journal Name: JOURNAL OF FLUORINE CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.348-355
  • Keywords: Supercritical carbondioxide, Mechanical properties, Fluomethacrylate copolymers, Free volume, Young's modulus, Glass transition, GLASS-TRANSITION TEMPERATURE, FREE-VOLUME, VINYLIDENE FLUORIDE, SURFACE-PROPERTIES, OPTICAL-PROPERTIES, YOUNGS MODULUS, POLYMERIZATION, BEHAVIOR, ANNIHILATION, DEPENDENCE
  • Kocaeli University Affiliated: No

Abstract

Poly( methyl methacrylate-ran-perfluoroalkyl ethyl methacrylate) copolymers having varying perfluoralkyl ethyl methacrylate ester (Zonyl-TM) contents were synthesized in supercritical CO2. Complete amorphous structures of the copolymers were verified by XRD. Young's modulus (Y-mod) of the copolymers was decreased linearly from 1.57 to 1.08 GPa and T-g values from 102 to 77 C with the increase of Zonyl-TM content. A linear relationship between the Y-mod and the T, values of the copolymer was also found. The increase of the large branched pendant groups resulted in the increase of the free volume and a corresponding decrease in Ymod and T-g of the copolymers. A good fit was found when the Schneider equation was used. Negative deviation from the Gordon-Taylor equation was observed when Zonyl-TM content was lower than 14% due to rapid increase in free volume and then a positive deviation was found due to the dipole-dipole interactions between the methyl ester and fluoroalkyl ester groups. (C) 2011 Elsevier B.V. All rights reserved.