end capping

It is economical as well as effective method to take chemical end-capping modification of PPC and melt blending modify it with the help of biodegradable materials.

因此，对PPC进行化学封端改性，并借助其他可生物降解材料对其进行熔融复合改性，是一种既经济又有效的重要方法。

At the end capping stage, the reaction temperature is 120 ℃ at first and then 150 ℃, and the reaction time is 5 h. Under the optimum reaction conditions the yield of the product can be up to 86.7%.

在封端反应阶段，反应初期的适宜温度为120℃、后期以150℃为佳，适宜的反应时间为5h，在该条件下收率为86.7%。

Use of end capping agent to increase the yield of thermostable acetal copolymer

利用封端剂提高共聚甲醛的热碱稳定产物收率的研究

By using capping method, the side reactions can be eliminated and the polybutadiene with carbonate or ester end-group can be obtained.

氯代甲酸乙酯与聚丁二烯基锂发生偶联反应，采用戴帽方法，可消除偶联反应，合成出端碳酸酯基和端酯基遥爪聚丁二烯。

The reaction temperature is 150 ℃ and the reaction time was 5h in the end capping reaction.

封端反应中，反应温度150℃，反应时间5h；