P9 Ultrasonic degradation of methyl cellulose in aqueous solution(Poster Session)

DOI
  • Taguchi Kimihiko
    Department of Engineering, Graduate School of Engineering, Nagoya University
  • Matsuoka Tatsuro
    Department of Engineering, Graduate School of Engineering, Nagoya University
  • Koda Shinobu
    Department of Engineering, Graduate School of Engineering, Nagoya University

Bibliographic Information

Other Title
  • P9 水溶液中におけるメチルセルロースの超音波切断に関する研究(ポスターセッション)

Abstract

The mechanism of ultrasonic degradation is still obscure, but it is well accepted that cavitation bubbles are mainly responsible for the degradation. The intense shear field generated by the collapse of the cavitation bubbles induces chain scission. Most of investigations on ultrasonic degradation have been carried out at low ultrasonic frequency around 20kHz. In this work, the ultrasonic degradation of methyl cellulose in aqueous solution was studied at two frequencies (20kHz and 500kHz) at the constant calorimetric power (20W) and temperature (25℃). The time variation of the average molecular weights and the molecular distribution were determined by Gel Permeation Chromatography (GPC). The mass average molecular weights (M_w) decreases with sonication time. The large lowering of M_w was observed at the frequency 500kHz. The degradation rate was suppressed by the addition of t-BuOH which act as a radical scavenger. The ultrasonic degradation rate coefficient k_d was estimated and compared with the results of other water-soluble polymers. The order of k_d value were PEO > Dextran 〓 Pullulan > MC. We will discuss on the frequency effects on the ultrasonic degradation.

Journal

Keywords

Details 詳細情報について

  • CRID
    1390282681029709056
  • NII Article ID
    110009710368
  • DOI
    10.20577/pamjss.15.0_63
  • ISSN
    24241512
  • Text Lang
    ja
  • Data Source
    • JaLC
    • CiNii Articles
  • Abstract License Flag
    Disallowed

Report a problem

Back to top