端基对超支化高分子性质影响的研究

Effect of Terminal Groups on the Properties of Hyperbranched Polymers

对端羟基脂肪族超支化高分子的端基进行了乙酰化和硅烷化改性,研究了不同端基对超支化高分子的玻璃化温度,折光指数增量以及特性粘度的影响。结果表明,端基的极性减小使超支化高分子的玻璃化温度降低,不同端基的超支化高分子的折光指数增量也有很大差异,而强极性的端基使超支化高分子在溶液中易产生团聚作用。由于端基在超支化高分子中所占比重较大,端基是影响超支化高分子性质的重要因素。

The acetyl derivative and the silicane derivative of hyperbranched aliphatic polyesters with terminal hydroxy group were prepared. The effect of terminal groups on the properties was studied. From the results, it is found that the properties of the terminal groups strongly affect the properties of the hyperbranched polymers. The glass transition temperature and the refractive index increment have changed a lot after modification. More importantly, intrinsic viscosity \ of the modified hyperbranched polymer is much lower than that of the corresponding hydroxyl end group sample. This suggest that the stable associations (or clusters) in the original sample solution are formed by the hydrogen bond interaction.