Intramolecular and Intermolecular Interactions of Polymers with Heteroatoms

（1）聚硫醚的分子内相互作用通过NMR实验、从头计算和RIS分析，研究了聚硫乙烯和聚硫丙烯在θ态的构象特征，并与相应的聚醚进行了比较。从构型熵和分子间相互作用的角度对多硫化物的高熔点进行了解释。（2）聚乙烯亚胺（PEI）的构象分析通过分子轨道计算和核磁共振实验，计算了PEI的构象能。PEI的链尺寸被计算为氢键能的函数。分子间氢键形成的双链螺旋的焓也估计从MO计算。（3）聚硅烷的构象分析采用转动异构态方法和分子动力学模拟方法研究了聚二正丁基硅烷、聚二正己基硅烷和聚甲基正丙基硅烷的构象特征。由此计算的特征比与光散射法测定的特征比相当一致。的聚硅烷的相变，溶解性，和紫外吸收成功地与构象特征。（4）高分子液晶模型化合物的构象分析通过热分析、X-射线衍射、氘核磁共振等方法研究了低聚物模型化合物与高分子液晶的结构-性能关系。和水，但也在一个无水液晶已研究了氘NMR。

(1)Intramolecular Interactions of PolysulfidesConformational characteristics of poly(ethylene sulfide) and poly(propylene sulfide) in the theta state have been investigated by NMR experiments and ab initio molecular orbital (MO) calculations for the monomeric model compounds and RIS analysis of configuration-dependent properties of the polymers, and compared with those off the corresponding polyethers. The high melting points of the polysulfides have been elucidated in terms of configuration entropy and intermolecular interactions.(2)Conformational Analysis of Poly(ethylene imine) (PEI)Conformational energies of PEI have been evaluated from MO calculations and NMR experiments for its monomeric model compound, N,N'-dimethylethylenediamine. The chain dimension of PEI was calculated as a function of the hydrogen-bond energy. The enthalpy of the intermolecular hydrogen bond formed in the double-stranded helix was also estimated from MO calculations.(3)Conformational Analysis of PolysilanesConformational characteristics of poly(di-n-butylsilane), poly(di-n-hexylsilane), and poly(methyl-n-propylsilane) have been investigated by a rotational isomeric state scheme with molecular dynamics simulations. Characteristic ratios thus calculated were in fairly good agreement with those determined by light scattering. The phase transition, solubility, and UV absorption of the polysilanes were successfully correlated with the conformational characteristics.(4)Conformational Analysis of Model Compounds of Polymer Liquid CrystalsStructure-property correlations of model compounds of oligomer to polymer liquid crystals have been investigated by thermal analysis, X-ray diffraction, deuterium NMR, etc. Conformational characteristics of 1-butanol incorporated, not only in a lyotropic liquid crystal of sodium octanoate, 1-butanol, and water but also in a nematic liquid crystal have been investigated by deuterium NMR.