We previously reported the quantitative main-chain scission reaction of polymers by a conjugate substitution reaction in aqueous ammonia, although the detailed behavior of the reaction was not analyzed. Herein, the degradation of a poly(conjugated ester), prepared from 1,4-butylene bis[α-(bromomethyl)acrylate] and fluorescein, with aqueous solution of various nucleophiles was investigated. Direct observation using UV‒vis spectrometry was effective for the analysis at the earliest stage of degradation, while size-exclusion chromatography was used for long-term degradation. The main-chain scissions were observed by a conjugate substitution reaction with ammonia, n-propylamine, diethylamine and α-amino acids, while similar degradation was observed with sodium acetate and water in the presence of triethylamine as a catalyst. The nucleophilicity of the nucleophiles and their affinity for the polymer affected the reaction rates in the earliest stage. On the other hand, to achieve complete chain scission, ammonia was most effective, probably because the dissolution of the degradation products led to the exposure of new polymer surfaces.

我们之前报道了通过氨水中的共轭取代反应进行聚合物的定量主链断裂反应，尽管没有分析该反应的详细行为。在此，研究了由 1,4-丁烯双[α-(溴甲基)丙烯酸酯]和荧光素制备的聚（共轭酯）在各种亲核试剂的水溶液中的降解。使用紫外-可见光谱法直接观察对于降解的最早阶段的分析是有效的，而尺寸排阻色谱法用于长期降解。通过与氨、正丙胺、二乙胺和α-氨基酸的共轭取代反应观察到主链断裂，而在三乙胺作为催化剂存在下，用乙酸钠和水观察到类似的降解。亲核试剂的亲核性及其对聚合物的亲和力影响最早阶段的反应速率。另一方面，为了实现完全断链，氨是最有效的，可能是因为降解产物的溶解导致新的聚合物表面暴露。