環氧樹脂混合不同pH值酚液化柳杉製備摻合樹脂之性質

PROPERTIES OF BLENDED RESINS PREPARED BY MIXING EPOXY RESIN WITH PHENOL-LIQUEFIED CRYPTOMERIA JAPONICA AT DIFFERENT PH VALUES

康甄玲(Chen-Ling Kang) ； 李文昭(Wen-Jau Lee)

《中華林學季刊》 50卷2期 (2017/06) Pp. 117-130

摘要

本研究利用雙酚A與環氧氯丙烷反應合成環氧樹脂。將柳杉(Cryptomeria japonica Don.；Japanese cedar)木粉以酚為溶劑，鹽酸及硫酸為催化劑進行液化處理分別得LW-C及LW-S兩種液化木材，並將其pH值調整為0.5、4.0、7.0及9.0。隨後將環氧樹脂與液化柳杉以重量比100/50混合製備摻合樹脂，並添加樹脂液重10%之三乙基四胺為硬化劑，探討液化柳杉種類及pH值對摻合樹脂硬化性、熱性質及膠合性能之影響。由結果得知，摻合樹脂硬化過程為一放熱反應，隨液化柳杉pH值提高，摻合樹脂之放熱溫度降低，膠化時間延長。DSC熱分析結果顯示，添加LW-C之摻合樹脂在硬化過程之放熱量大於添加LW-S者，其中添加LW-C者之反應熱隨pH值提高而減少，添加LW-S者則隨pH值提高而增加。硬化摻合樹脂之TGA分析結果顯示，在加熱溫度300℃前以pH值0.5者有較佳之熱抵抗性，然300℃以上則以採用較高pH值之液化柳杉者熱抵抗性較佳。添加LW-C之摻合樹脂之木材膠合強度優於添加LW-S者，且隨LW-C之pH值提高，膠合強度增加，其常態膠合強度可達CNS 11031號標準膠合強度9.6 MPa之要求以上。

關鍵字

摻合樹脂 ； 膠合強度 ； 柳杉 ； 環氧樹脂 ； 酚液化木材

並列摘要

In this study, epoxy resin was synthesized by reacting bisphenol A with epichlorohydrin. Liquefied woods, named LW-C and LW-S, were obtained by liquefying Cryptomeria japonica wood powders in phenol respectively with HCl and H_2SO_4 as catalyst. The pH values of liquefied C. japonica were adjusted to 0.5, 4.0, 7.0 and 9.0. The blended resins were prepared by mixing epoxy resin with liquefied C. japonica with the weight ratio of 100/50 and triethylenetetramine at 10% of resin weight was added as the hardener. The influence of the kind and pH value of liquefied C. japonica on the curing behavior, thermal properties and adhesion performances of blended resins were investigated. The results show that the curing process of blended resins was an exothermic reaction. Increasing the pH value of the liquefied C. japonica, decreased the exothermic temperature of blende resin and extended the gel time. DSC analysis results show that blended resins prepared by mixing with LW-C had more released heat than that with LW-S. The released heat decreased as the pH value increased for LW-C, while it increased for LW-S. TGA results show that cured blended resins that prepared with liquefied C. japonica with the pH value of 0.5 had better heat resistance at temperature lower than 300℃. However, when the temperature higher than 300℃, blended resins prepared by mixing liquefied C. japonica with higher pH values showed a better heat resistance. Blended resins mixed with LW-C had the wood bonding strength higher than that mixed with LW-S. In addition, increasing the pH value of LW-C, the bonding strength increased. They had the dry bonding strength over 9.6 MPa, which could fit the request of CNS 11031 standard.

並列關鍵字

Blended resins ； Bonding strength ； Cryptomeria japonica ； Epoxy resin ； Phenol-liquefied wood