Formation of Junction Zones in Thermoreversible Gelation Process of Ethylene-Propylene Random Copolymer/Toluene Systems.

DOI Web Site Web Site 20 References
  • Okada Motoyuki
    Department of Fine Materials Engineering, Faculty of Textile Science and Technology
  • Tsuchiya Yuko
    Department of Fine Materials Engineering, Faculty of Textile Science and Technology
  • Okabe Masaru
    Department of Chemical Technology, Faculty of Engineering, Kanagawa Institute of Technology
  • Takahashi Masato
    Department of Fine Materials Engineering, Faculty of Textile Science and Technology
  • Matsuda Hideomi
    Department of Fine Materials Engineering, Faculty of Textile Science and Technology

Search this article

Abstract

Melting behaviour of ethylene-propylene random copolymer (EP random copolymer)/toluene thermoreversible gels was measured by the falling ball method (FBM) and differential scanning calorimetry (DSC). By applying the theory proposed by Takahashi, Nakamura and Kagawa (Takahashi theory) to the gel melting temperature Tgm measured by FBM, values of number of monomers ξ per chain in a junction point were evaluated. Further, values of ζ and s were evaluated by the Tanaka theory. ζ in Tanaka theory has the same physical meaning as ξ in Takahashi theory and s means the number of polymer chains contained in a junction point. The obtained values of ζ have the same order of magnitude but smaller than ξ. In DSC measurements, the enthalpy of melting (ΔHm) of junction points was measured. ΔHm increases with the increase of gelation time, and then approaches a constant value. The gelation time th, which is necessary to reach the equilibrium value of ΔHm, is extremely longer than the gelation time tm, which is necessary to obtain a constant value of Tgm.

Journal

  • Sen'i Gakkaishi

    Sen'i Gakkaishi 56 (2), 104-108, 2000

    The Society of Fiber Science and Technology, Japan

References(20)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top