雙酚A型／含液化木材型環氧樹脂製備摻合樹脂之硬化特性及其成型物之性質

Curing Behavior of Blended Resins Prepared with Bisphenol A Type and Liquefi ed Wood Type Epoxy Resin and the Properties of Their Moldings

本研究將柳杉木材以重量比7/3之酚／雙酚A混合液進行液化處理，將液化柳杉（liquefied Cryptomeria japonica; LW）及雙酚A分別與環氧氯丙烷反應製備液化柳杉型（LW-ER）及雙酚A型（ER）環氧樹脂。隨後將ER樹脂及LW-ER樹脂以重量比100/0、75/25、50/50、25/75、0/100混合製備摻合環氧樹脂，並分析摻合樹脂之硬化特性，及硬化摻合樹脂之物理、機械性質、黏彈性及熱抵抗性。由試驗結果得知，ER樹脂為分子量小於1000 g/mol，LW-ER樹脂之重量平均分子量8332 g/mol，最大可達100000 g/mol以上。熱示差掃描卡量（Differential scanning calorimetry; DSC）分析結果顯示，隨ER/LW-ER重量比降低（LW-ER樹脂含量增加），摻合樹脂硬化反應之放熱峰向高溫側偏移，放熱峰高度及反應熱減少。添加LW-ER樹脂可提高硬化摻合樹脂之撓性，但抗彎強度及丙酮溶出之重量保留率則降低。動態熱機械分析（Dynamic mechanical analysis; DMA）結果顯示，ER與LW-ER間具有良好之相容性，添加LW-ER樹脂主要影響硬化樹脂分子鏈之熱活動性。熱重分析（Thermogravimetric analysis; TGA）結果顯示，添加LW-ER樹脂則可提高ER樹脂之熱抵抗性。 In this study, wood of Cryptomeria japonica was liquefied in the mixture of phenol and bisphenol A that had the weight ratio of 7/3. The liquefi ed C. japonica and bisphenol A were reacted with epichlorohydrin to synthesize the liquefi ed C. japonica type (LW-ER) and bisphenol A type (ER) epoxy resin, respectively. The blended epoxy resins were prepared by mixing ER resin and LW-ER resin with the weight ratio of 100/0, 75/25, 50/50, 25/75, and 0/100. The curing behavior of blended resins and the physical, mechanical, viscoelasticity, and heat resistance of cured resins were investigated. The results show that ER resin had the molecular weight lower than 1000 g/mol. Whereas, LW-ER resin had the weight average molecular weight of 8332 g/mol and had the maximum molecular weight larger than 100000 g/ mol. Differential scanning calorimetry analysis showed that decreased the ER/LW-ER weight ratio, i.e. a more LW-ER contented, the exothermic peak caused by curing reaction shifted to higher temperature with a lower peak height and less reaction heat. Adding LW-ER resin could increase the fl exibility of cured resin. However, the bending strength and weight retention after acetone immersed decreased. Dynamic mechanical analysis showed that ER and LW-ER had good compatibility. The mainly infl uence of adding LW-ER resin was on the thermal activity of molecular chain of cured resins. Thermogravimetric analysis showed that the heat resistance of ER resin could be improved by adding LW-ER resin.