液晶型環氧樹脂硬化反應動力學與性質研究

Study Curing Kinetic and Properties of Liquid Crystalline Epoxy Resins

黃建睿(Jien-Ruei Huang)

指導教授 ： 林唯芳

國立臺灣大學/工學院/高分子科學與工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.10310

摘要

本文的研究著重於環氧樹脂與交聯劑的反應動力學與各項性質的探討，其中環氧樹脂採用的是自行合成的液晶型環氧樹(BP, AM)脂與市售的非液晶型環氧樹脂(TMBP, DGEBA)，交聯劑選用的是分子結構較剛硬的DDS，與分子結構較柔軟的DDE。
經由動力學的研究，我們可發現DDE的活化能較低，反應速率較快，但產品的機械性質較差，然而DDS活化能雖高，但由於DDS的分子結構較剛硬，因此其機械性質較佳，適合用於航空材料。
我們利用自催化模型來描述Epoxy/amine的反應過程，利用DSC得到此模型的四個反應參數，利用這些參數我們便可調控我們的交聯溫度與時間，在此研究中發現隨著溫度不斷的提升，理論模型所預測的結果會與實驗的結果越來越符合。
利用反應動力學所得的結果來設計硬化過程所需的溫度與時間，可大大縮短黃宏文在2001年時所設計的交聯時間。
根據實驗所得的結果我們發現Epoxy/DDS的機械性質比Epoxy/DDE的機械性質要強很多，而液晶型環氧樹脂的機械性質也比非液晶型環氧樹脂強，因此我們可將液晶的排列視為一種自增強(self-reinforced)效應，此效應帶來的好處就是不需額外添加纖維就可達到相當高的機械強度。

關鍵字

液晶 ； 環氧樹脂 ； 動態反應動力學 ； 恆溫反應動力學 ； 自催化模型

並列摘要

The goal of this research focuses on the kinetic and material properties of the epoxy resin systems and the curing agents selected. The epoxy resins studied in the research is self-synthesized liquid crystalline epoxy resins (BP, AM) and commercial non-liquid crystalline epoxy resins (TMBP, DGEBA). One of the curing agents, DDS, has a more rigid molecular structure. The other curing agents, DDE, has softer molecular structure.
From the kinetic study, we can find that Epoxy/DDE has lower activation energy and react faster than Epoxy/DDS. But Epoxy/DDE systems possess poorer mechanical properties when made into bulk materials. The curing agent, DDS, possess a more rigid molecular structure. Hence, Epoxy/DDS results in better mechanical properties and is suitable to be used in aerospace applications.
We apply autocatalytic model to described the reaction of epoxy/amine systems. The parameters of the model can be obtained through DSC measurement and be used to adjust the curing time and temperature for the reaction. We have found the prediction of model is better fitting experimental results as the reaction temperature increases.
Modifying the curing process according to the result of the kinetic study, we are able to reduce the curing time designed by Huang in 2001.
According to the experimental results, we found that the mechanical properties of Epoxy/DDS are better than that of Epoxy/DDE and the mechanical properties of liquid crystalline epoxy resin are better than that of non-liquid crystalline epoxy resin. As a result, we can view the alignment of the liquid crystal as a self-reinforced effect which can increase the composite’s mechanical properties without adding extra fibers.

並列關鍵字

liquid crystalline ； epoxy resin ； dynamic kinetic ； isothermal kinetic ； autocatalytic model

參考文獻

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