| 摘要註: |
本研究以溶膠-凝膠法(sol-gel process)製備環氧樹脂/二氧化矽奈米複合材料,經偶合劑(3-Isocyanatopropyltriethoxysilane,IPTES)改質環氧樹脂(Diglycidyl ether of bisphenol A,DGEBA),使有機/無機材料間具共價鍵而不易產生相分離;利用微差掃瞄熱分析儀(DSC)分析材料的熱性質,並透過自催化反應動力學模式 (Autocatalytic kinetic mechanism)推導對固化反應之動力探討;針對(1)固化溫度系統、(2)改質系統、(3)固含量(TEOS)系統、(4) PH值系統,製備出ET5-PH 2.5、MT5-PH2.5、MT10-PH2.5及MT10-PH9.5四組環氧樹脂/二氧化矽奈米複合材料。本研究發現:(1)固化溫度的提昇對轉化率與反應速率有正向作用、(2)改質環氧樹脂在PH2.5環境下,有助於反應速率提升並對轉化率有2.4~4.2%提升效應、(3)固含量增加(5%~10%)可增進固化反應效率,但達一定濃度時,粒子會產生團聚現象,成品開始變半透明狀、(4)在PH2.5下,反應速率、轉化率與動力常數值皆有良好表現;四組系統中,MT5-PH2.5整體反應性最好且呈現透明狀、(5)由反應動力反應動力常數推導對實驗常數比較,需考慮到反應前期化學控制與後期物理控制。 In this study, epoxy resin/silicon dioxide nanocomposite is prepared by sol-gel process, diglycidyl ether of bisphenol A (DGEBA) is modified by coupling agent 3-Isocyanatopropyltriethoxysilane (IPTES) to form covalent bond between organic and inorganic materials so that phase separation cannot take place easily; this paper analyzes thermal property of material by differential scanning calorimeter (DSC), and discusses cure reaction kinetics through autocatalytic kinetic mechanism; four groups of epoxy resin/silicon dioxide nanocomposite (ET5-PH2.5, MT5-PH2.5, MT10-PH2.5 and MT10-PH9.5) are prepared based on (1) curing temperature system, (2) modification system, (3) solid content (TEOS) system, (4) PH value system. In this study, it is observed that: (1) the rise of curing temperature has positive effect on conversion rate and reaction speed; (2) under PH2.5, modified epoxy resin helps to accelerate reaction and increase conversion rate by 2.4~4.2%; (3) the increase of solid content (5%{212261}10%) may improve curing reaction efficiency, but when it reaches certain concentration, particles will agglomerate, and the reacted products start to be semitransparent; (4) under PH2.5, reaction speed, conversion rate and kinetic constant all are satisfactory; among these four groups, MT5-PH2.5 shows best overall reactivity and transparency; (5) the comparison between reaction kinetic constant reflected by reaction kinetics and experiment constant should consider chemical control at the beginning of reaction and physical control at the end. |