Study on Relaxation of Entanglement Network Structure with Use of Differential Dynamic Modulus as a Probe

以微分动模量为探针的纠缠网络结构弛豫研究

• 批准号: 04805090
• 负责人: ISONO Yoshinobu
• 金额: $ 1.15万
• 依托单位: NAGAOKA UNIVERSITY OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04805090/
• 关键词: Dynamic modulus; Entanglement; Viscoelastic Properties; Nonlinear; Relaxation modulus; Polybutadiene; Cross-link; Hydrosilation; 絡み合い; 大変形; ずり変形; アニオン重合

We have prepared four monodisperse polybutadienes (Mw = 1.4x10^5-7.2x10^5d) by anionic polymerization technique. Vinyl contents of the samples were all 70%. Quantitative interomolecular cross-link can be introduced to the samples by hydrosilation with p-bis(dimethylsilyl)-benzene. In this study, lightly cross-link (Mc/Me-7) was introduced. Under large shearing deformations, anisotropic conformation of the chain occurs in both uncroo-linked and cross-linked samples, but there is no change in entanglement density in the latter sample.We have observed the change in entanglement network structure in both samples under large shearing defotrmations with the use of differential dymnamic modulus as a probe. Differential dynamic modulus can be measured by superposed small oscillatory deformation on a large shearing deformation at a frequency falls down in the middle of the rubbery plateau. Deformations were given in a single-step and double-step fashions. The results were discussed with Doi-Edwards Tube Model and BKZ Model. It can be concluded that there is clear correspondence between nonlinear viscoelastic properties of polymer dense systems and change in entanglement network structure, and change in entanglement network structure under large deformations are due to two factors of chain anisotropy and decrease in entanglement density.

我们用阴离子聚合技术制备了四种单分散聚丁二烯(MW=1.4×10~(-5)~7.2×10~(-5)d)。样品的乙烯基含量均为70%。通过对二甲基硅基苯的硅氢化反应，可以在样品中引入定量的分子间交联剂。在本研究中，引入了轻度交联剂(Mc/Me-7)。在大剪切变形下，未交联样品和交联样品都出现了链的各向异性构象，但后一种样品的纠缠密度没有变化。我们以差动动模为探针，观察了两种样品在大剪切变形下的纠缠网络结构的变化。将橡胶高原中部某一频率下降的小振荡变形叠加到大剪切变形上，即可测得差动模。变形采用单步和双步两种方式。用Doi-Edwards管模型和BKZ模型对计算结果进行了讨论。结果表明，聚合物稠密体系的非线性粘弹性性质与缠结网络结构的变化有明显的对应关系，大变形下缠结网络结构的变化是由于链各向异性和纠缠密度降低两个因素所致。

项目成果

ISONO,Yoshinobu: "“Differential Dynamic Modulus of Lightly Cross-linked Polymers"" to be submitted to Macromolecules.

ISONO, Yoshinobu：““轻度交联聚合物的微分动态模量””将提交给 Macromolecules。

ISONO,Yoshinobu: ""Differential Dynamic Modulus of Lightly Cross-linked Polymers"" (to be submitted to Macromolecules).

ISONO,Yoshinobu：“轻度交联聚合物的微分动态模量”（将提交给Macromolecules）。

ISONO,Yoshinobu: "“Differential Dynamic Modulus of Linear Polymers Having Sharp Molecular Weight Distributions in Large Shearing Deformations."" submitted to Macromolecules.

ISONO, Yoshinobu：““大剪切变形中具有尖锐分子量分布的线性聚合物的微分动态模量。”提交给《高分子》。

ISONO,Yoshinobu: ""Differential Dynamic Modulus of Linear Polymers Having Sharp Molecular Weight Distributions in Large Shearing Deformations."" (submitted to Macromolecules).

ISONO，Yoshinobu：“大剪切变形中具有尖锐分子量分布的线性聚合物的微分动态模量。”（提交给Macromolecules）。