1.1.4　Linear Polymers

A linear polymer（线型聚合物）consists of a long chain of skeletal atoms which are attached to the substituent groups.Polystyrene（聚苯乙烯，PS）or polyethylene is one of the simplest examples.Linear polymers are usually soluble in some solvent，and in the solid state at normal temperatures，they exist as elastomers（弹性体），flexible materials（韧性材料），or glasslike thermoplastics（热塑性树脂）.In addition to polyethylene，typical linear-type polymers include poly（vinyl chloride）（聚氯乙烯，PVC），poly（methyl methacrylate）（聚甲基丙烯酸甲酯，PMMA），polyacrylonitrile（聚丙烯腈，PAN）and Nylon-66（尼龙-66）.

Chain structure of a linear polymer：