結合活性自由基聚合和開環聚合以合成嵌段共聚物

The hybridization of controlled radical polymerization and ring opening polymerization

呂逸民(Liu, Yi Ming)

指導教授 ： 彭之皓

國立清華大學/理學院/化學系/碩士(2015年)

https://doi.org/10.6843/NTHU.2015.00093

摘要

論文是以苯甲醛 / 二氯二茂鈦 / 奈米鋅 的系統催化苯乙烯 (Styrene，St) 的自由基聚合反應，得到符合活性特徵的聚苯乙烯 (Polystyrene，PSt)。
在苯甲醛 / 二氯二茂鈦 / 奈米鋅 / 苯乙烯的自由基聚合系統，改變苯甲醛、二氯二茂鈦、以及奈米鋅當量數去探討每個變因對於苯乙烯自由基聚合反應之影響。0.5 / 4 / 8 / 100的條件下，聚苯乙烯高分子分子量與單體轉化率呈線性成長，可得較小的 PDI 值 (1.38)，且分子量與理論值相近。
以苯乙烯為大分子起始劑進行己內酯的開環聚合反應，成功合成出 polystyrene-b-polycaprolactone (PSt-b-PCL) 嵌端共聚物。接著嘗試利用一鍋煮來更有效率製造出 PSt-b-PCL，經過諸多比例的測試，0.5 / 4 / 4 / 300 / 60 為較佳條件。為了得到更小 PDI值 的 PSt-b-PCL，期望利用變溫實驗合成更小 PDI 值的嵌端共聚物。在 90 °C下的苯乙烯自由基聚合是較佳的變溫實驗。

關鍵字

活性自由基聚合 ； 開環聚合 ； 嵌段共聚物

並列摘要

Benzaldehyde / Cp2TiCl2 / nano-zinc system could catalyze radical polymerization of styrene. The polystyrene with a contolled/living character was obtained.
In benzaldehyde / Cp2TiCl2 / nano-zinc system, in order to dicuss how every factor would affect the radical polymerization of styrene, the equivalent of Cp2TiCl2, nano-zinc, and benzaldehyde was changed. The condition of 0.5 / 4 / 8 / 100 revealed a living radical polymerization, the polystyrene polymer chain was growth with conversion linearly and agree to the theoretical molecular weight, the polystyrene had low polydispersities index (PDI).
The polystyrene-b-polycaprolactone was synthesized by ring opening polymerization of ε-caprolacotone from polystyrene. Because benzaldeyde could inititate radical polymerization and ring opening polymerization, the idea was futher utilized in the synthesis of PSt-b-PCL in one-pot reaction. In one-pot reaction, 0.5 / 4 / 4 / 300 / 60 was better condition compared with other ratios. In order to get polystyrene-b-polycaprolactone which had narrow dispersities, utilizing strategy of chain extension of polystyrene at different temperature from polycaprolactone. Chain extension of polystyrene at 90° C from polycaprolactone was better results compared with 75° C and 110° C.

並列關鍵字

controlled radical polymerization ； ring opening polymerization ； block copolymer

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