核磁共振研究溶胀AB-交联聚合物中的分子运动

测定了溶胀的PPU/PSAB 交联聚合物中链段和侧基的13CT1和NOE ,用VJGM模型和三等价位跃迁内旋转、扩散内旋转以及等价、不等价两位置跃迁内旋转模型分析了其中的主链链段运动和侧基内旋转运动 ,求出了主链和侧基的运动相关时间、扩散系数和活化能等参数 .结果表明PS含量对PPU运动的影响极小 ,PS主链运动活化能与PPU含量存在线性关系 .丙烯酸与苯乙烯共聚对PPU的运动几乎无影响

Study of the molecular motion in swollen AB-crosslinked polymer by NMR

The 13 C T 1 and NOE ofmain chain and side group of swollen PPU/PS AB\|crosslinked polymer(i.e.ABCP) are measured. The segmental motion of main chain and internal rotation of side group of the ABCP are analyzed by means of VJGM model and three\|site jump internal rotation, diffusion internal rotation, equal and unequal two\|site jump internal rotation model. The motion parameters such as correlation times, diffusion coefficients and active energy of the main chain and side group are calculated. The results show that the effect of content of PS on the motion of PPU is insignificant, but PPU has restrictive effect on the motion of PS. There is a linear relationship between the activation energy of the main chain of PS and the content of PPU. The copolymerization of acrylic acid with styrene has little effect on the motion of PPU.