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)

DOI

書誌事項

タイトル別名
  • P9 Ultrasonic degradation of methyl cellulose in aqueous solution(Poster Session)

抄録

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.

収録刊行物

詳細情報 詳細情報について

  • CRID
    1390282681029709056
  • NII論文ID
    110009710368
  • DOI
    10.20577/pamjss.15.0_63
  • ISSN
    24241512
  • 本文言語コード
    ja
  • データソース種別
    • JaLC
    • CiNii Articles
  • 抄録ライセンスフラグ
    使用不可

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