The 13C-NMR characterization of polystyrene which is soluble in 2-butanone shows that some syndiotactic polystyrene segment exists in the product.

• 由13C-NMR表征结果表明：在以ETCA为活性剂的催化体系催化苯乙烯聚合，得到聚合产物的丁酮可溶部分中含有间规立构聚苯乙烯链段。