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首页> 外文期刊>Journal of Applied Polymer Science >The Rheological and Structural Behavior of Silylcellulosics Derivatives
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The Rheological and Structural Behavior of Silylcellulosics Derivatives

机译：硅纤维素衍生物的流变和结构行为

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The trimethylsilylcellulose (TMSC) samples were characterized in solution by osmometry, viscometry, and gel permeation chromatography. The Mark-Houwink- Sakurada (M-H-S) equation coefficients were determined in chloroform, 1,1,1-trichlo- roethane, and o-xylene, in all cases the exporient "a" being higher than unit, this indicating a great stiffness of the macromolecules in solution. Also, the temperature dependence of the limiting viscosity number and M-H-S coefficients respectively for TMSC in o-xylene were studied. The exponent from M-H-S equation is also higher than unit, and increases linearly with the temperature. The GPC studies indicates a relative high polydispersity of the studied samples; the polydispersity index being situated between 2 and 3. The change of the crystalline structure as the result of silylation reaction was evidenced, the crystallinity of silyl derivatives depending on the substi- tution degree (DS), and the molecular weight. The viscous flow parameters for dilute solutions of trimethylsilylcellulose in o-xylene were determined in the temperature range 30-70degC. The temperature dependence of the dynamic viscosity of the solutions obeys an Arrhenius-type equation in which the apparent activation energy is linearly dependent on both the solution's concentration and molecular weight. For preexponen- tial factor no significant dependence on concentration and molecular weight was found. This behavior was attributed to the very great stiffness of the macromolecular chains.
机译：通过渗透压测定，粘度测定和凝胶渗透色谱法在溶液中表征三甲基硅烷基纤维素（TMSC）样品。 Mark-Houwink-Sakurada（MHS）方程系数是在氯仿，1,1,1-三氟乙烷和邻二甲苯中测定的，在所有情况下，“ a”值均高于单位，这表明其较高的刚度溶液中的大分子。此外，还研究了在邻二甲苯中TMSC的极限粘度数和M-H-S系数的温度依赖性。 M-H-S方程的指数也高于单位，并且随温度线性增加。 GPC研究表明，所研究样品具有较高的多分散性。多分散指数在2和3之间。甲硅烷基化反应的结果表明晶体结构发生了变化，甲硅烷基衍生物的结晶度取决于取代度（DS）和分子量。在30-70℃的温度范围内测定三甲基甲硅烷基纤维素在邻二甲苯中的稀溶液的粘性流动参数。溶液动态粘度的温度依赖性遵循Arrhenius型方程，其中表观活化能与溶液的浓度和分子量均线性相关。对于指数前因子，没有发现对浓度和分子量的显着依赖性。该行为归因于大分子链的非常高的刚度。

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