Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/3371
標題: Study on Nylon 6 Synthesis via Anionic Polymerization Using Azetidine-2,4-diones as the Activators
以Azetidine-2,4-diones為活化物經由陰離子開環聚合反應合成耐綸6之研究
作者: 魏欣怡
Hsin-Yi, Wei
關鍵字: Anionic polymerization;azetidine-2;4-diones;ring open;Nylon 6
出版社: 化學工程學系
摘要: 
此論文主要利用本實驗室發展之多種具備Azetidine-2,4-dione官能基之單體為活化物,在無溶劑的環境下,與己內醯胺進行陰離子開環聚合反應,一步合成製備耐綸6,並進行一系列關於聚合溫度、活化物濃度、官能基數、活化物結構對陰離子開環聚合速率的影響之比較,了解陰離子開環聚合反應進行時活化物之構造與聚合速率及結晶速率的關係,使之可以直接應用於反應射出成型的加工上。
在芳香族Azetidine-2,4-diones為活化物的系統中,發現在3,3’-位置的取代基種類對轉化率及結晶時間有顯著的影響,其中由MDI所合成3,3’-位置具有雙乙基或乙基-丁基取代基的的芳香族Bis-Azetidine-2,4-dione為最佳的活化物選擇,其聚合速率約是一般文獻及市場最常使用之N,N’-Isophthaloyl-bis-ε-caprolactam的2倍,是至今所嘗試的所有化合物中最能活化陰離子聚合耐綸6的化合物。和預期不同的是,當3,3-位置取代基為立體障礙較小的甲基時,結晶速率及轉化率的表現反而較差,推測是進行陰離子開環聚合時容易產生分枝(branching)或交聯(crosslinking)的現象所導致。
此外,更進一步嘗試用雙官能基的Azetidine-2,4-diones與長鏈段的PPG-diamine製備成末端帶有Azetidine-2,4-dione Ring的高分子活化物,利用陰離子聚合法製備出三區段的團聯共聚物。在合成三區段團聯共聚物的系統中,高分子活化物的濃度愈高,即軟鏈段重量比例增加時,則會降低聚合的速率及轉化率。經由DSC、AFM及NMR分析確定利用此法可將軟鏈段改質劑經由化學鍵結方式導入硬鏈段之耐綸6主鏈中,並可觀察到規則微相分離之現象。

This research focused on the study of anionic ring-opening polymerization of caprolactum to synthesize Nylon 6 using structurally varied azetidine-2, 4-diones as the activators. The polymerizations were carried out by a one-step melt-process to find out the effects of activator's concentration, types (aromatic or aliphatic), functionalities ( n=1 and 2), substituents (on azetidine-2,4-dione ring) as well as those of reaction temperature on polymerization rates. The aim is to find the best activator and optimal condition for possible application in reaction injection polymerization of Nylon 6 (Nylon RIM).
In the aromatic series, different aliphatic substituent groups at 3,3'-prosition of azetidine-2,4-dione rings showed great effects on conversion rate and time of Nylon 6's crystallization. It was found that aromatic bisazetidine-2,4-diones based on MDI with 3,3'-diethyl- or 3-ethyl-3'-butyl-groups exhibited the best overall performances which were twice as fast than that of N,N'-isophthaloyl-bis-caprolactam in getting high molecular weight Nylon 6 (molecular wt. of ~70,000) in about 70 seconds at 140℃. Unexpectedly, substitution of less-hindered di-methyl groups at 3, 3'-positions of the ring resulted in a slower polymerization and crystallization of Nylon 6. Complications of cross-linking and branching in the polymerization seemed responsible for this abnormality.
Further study on Nylon-6 polymerizations were also conducted with bis-azetidine-2, 4-diones possessing long-chained polyether groups derived from Jeffamine D4000 Polymerization of Nylon-6 on the azetidine-2,4-dione prepolymers resulted in the formation of triblock-type systems. As might be expected in these cases, the polymerization rate of caprolactum was inversely proportional to the content of polyether groups in the prepolyemrs due to dilution. The triblock polymer prepared exhibited a well-organized phase-segregation in its morphology.
URI: http://hdl.handle.net/11455/3371
Appears in Collections:化學工程學系所

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