论文部分内容阅读
利用Flory的构象统计理论和改进的大侧基 旋转异构态模型方法,推导了对称双取代基链均方回转半径特征比〈S2〉/2xl2和温度系数d(ln〈S2〉)/dT公式,可以研究聚硅氧烷链的柔性及温度特性.根据聚二甲基硅氧烷链(PDMS)特征比与链长x关系和均方回转半径与温度T关系的公式,计算得到PDMS长链特征比和温度系数分别为1.086和0.76×10-3deg-1,与实验值分别为1.07和0.51×10-3～0.78×10-3deg-1范围符合.结构式为 [Si(C2H5)2O]x 和 [Si(C2H7)2O]x 的聚硅氧烷链具有比PDMS更大的特征比,因此它们的柔顺性相对变弱.
Based on Flory’s conformational statistics theory and the improved large-base rotational isomerism model, we derive the mean square radius of gyration radius of the symmetrical double-substituent chain as / 2xl2 and temperature coefficient d (ln ) / dT , We can study the flexibility and temperature characteristics of the polysiloxane chains.According to the relationship between the PDMS characteristic ratio and the chain length x and the relationship between the mean square radius of gyration and the temperature T, The specific ratios and temperature coefficients were 1.086 and 0.76 × 10-3deg-1, respectively, which were in agreement with the experimental values of 1.07 and 0.51 × 10-3-0.78 × 10-3deg-1 respectively. The structural formula was [Si (C2H5) 2O] x And [Si (C2H7) 2O] x have a greater characteristic ratio than PDMS, so their pliability is relatively weaker.