精选优质文档-倾情为你奉上Unit 1 What are polymers?What are polymers? For one thing, they are complex and giant molecules and are different from low molecular weight compounds like, say, common salt.什么是高聚物？首先，他们是合成物和大分子，而且不同于低分子化合物，譬如说普通的盐。To contrast the difference, the molecular weight of common salt is only 58.5, while that of a polymer can be as high as several hundred thousand, even more than thousand thousands.与低分子化合物不同的是，普通盐的分子量仅仅是58.5，而高聚物的分子量高于105，甚至大于106。These big molecules or macr
