HOME    About this site    mypage    Japanese    library    university    Feedback

University of the Ryukyus Repository >
Faculty of Agriculture >
Bulletin >
The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus >
No.31 (1984/11) >

 
Title :CMC の非ニュートン流動と動的粘弾性(農芸化学科)
Title alternative :Non-Newtonian Flow and Dynamic Viscoelasticity of Carboxymethylcellulose Solutions (Department of Agricultural Chemistry)
Authors :田幸, 正邦
仲村, 実久
Authors alternative :Tako, Masakuni
Nakamura, Sanehisa
Issue Date :19-Nov-1984
Abstract :CMC, 分子量120,000,置換度0.80,の水溶液は1.5および2.0%濃度で塑性流動性を示し, それぞれの降伏値は6および10dyne/cm^2であった。流動指数は1.0%までは1.0,1.5および2.0%では屈折点前で1.1,後で1.6であった。ずり速度に対する屈折点の位置がキサンタンガムのそれらと一致した。動的粘弾性は2.0%で急激な増大が見られ, tanδは周波数に関係なくほぼ一定(1.8)であった。CMCのこのようなレオロジー特性は分子主鎖が部分的に会合していることによるものであることが認められた。
Non-Newtonian flow behavior and dynamic viscoelasticity of carboxymethylcellulose (CMC) solutions were measured using a rheogoniometer and their rheological properties were analyzed. Aqueous solutions of CMC at concentrations of 0.5 and 1.0% showed pseudoplastic behavior and those of 1.5 and 2.0% showed plastic behavior. The flow indices of the former were 1.0 and the latter were 1.1 before refraction point and 1.6 after it. The situation of the refraction points for shear rate were consistent with that of xanthan gum at concentration of 1.5 and 2.0%. The activation energy of flow of 1.0% CMC solution was 4.58Kcal/mole at a low temperature region and 5.95Kcal/mole at a high temperature region. Dynamic viscoelasticity of CMC solutions was remarkably high at 2.0%, and loss tangent was evaluated to be 1.8. This result indicated that intermolecular secondary bonding was formed partially. Dynamic viscoelasticity of CMC solutions increased at low temperature but decreased with increasing temperature, while loss tangent also decreased from 1.8 to 1.2 with increasing temperature from zero to 65℃. Thus, intermolecular secondary bonds seemed to be attributed to intra-and intermolecular hydrogen bonding.
Type Local :紀要論文
ISSN :0370-4246
Publisher :琉球大学農学部
URI :http://hdl.handle.net/20.500.12000/3964
Citation :琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus no.31 p.57 -66
Appears in Collections:No.31 (1984/11)

Files in This Item:

File Description SizeFormat
KJ00000162204.pdf587KbAdobe PDFView/Open