不同酚原料製備水溶性酚醛樹脂之硬化性及膠合性能

Curing Behavior and Bonding Performance of Water-soluble Phenol-formaldehyde Resins Prepared from Various Phenolic Raw Materials

本研究以石化酚（Petrochemical phenol; P）、液化木質素（Liquefied lignin; LL）及木材快速熱解油（Wood fast pyrolysis oil; PO）為原料合成水溶性高溫硬化型酚醛樹脂（Phenol-formaldehyde resins, PF），探討不同酚原料在合成過程之粘度變化及合成樹脂之性質，進一步探討經135℃、150℃及165℃加熱後之硬化樹脂及所製作合板之性能。由試驗結果得知，石化酚為原料之PF樹脂在合成過程粘度無明顯變化，重量平均分子量1526，DSC分析出現單一之明顯放熱峰，以LL及PO為酚原料者在反應過程粘度明顯上升，所得樹脂之分子量較大，其中LL-PF之DSC分析出現兩個放熱峰； TGA顯示採用較高熱硬化溫度者有較佳之熱抵抗性，不同酚原料比較，PF及LL-PF之熱抵抗性優於 PO-PF，且PO-PF之熱裂解反應較複雜，且熱抵抗性較低；以PF所製作合板之常態及耐水膠合強度可符合CNS 1349號標準之要求，以PO-PF為膠合劑並以150℃熱壓溫度者可具備合格之耐水膠合強度；PF及PO-PF為膠合劑之合板甲醛釋出量符合F1等級合板之要求，LL-PF則符合F2等級之要求。 Petrochemical phenol (P), liquefied lignin (LL) and wood fast pyrolysis oil (PO) were used as raw materials to prepare water-soluble high temperature setting phenol-formaldehyde resins (PF). The viscosity variation during synthesis and the properties of prepared resins were investigated. Moreover, the performances of set resins and plywoods those heated with 135, 150, and 165℃ were also investigated. The results show that it had no significant viscosity changing during synthesis for PF resin prepared with petrochemical phenol as raw material. It had the weight average molecular weight of 1526 and an obvious exothermic peak during DSC analysis. On the other hand, resins prepared with LL and PO as raw materials had an obvious increasing in viscosity during synthesis and had the molecular weight larger than that with petrochemical phenol. It appeared two exothermic peaks for LL-PF during DSC analysis. TGA shows that the higher temperature for thermal setting the better thermal resistance for set resins had. Comparing among various phenolic raw materials, resins of PF and LL-PF had better thermal resistance. PO-PF had lower thermal resistance accompanied with a more complex thermal degradation. Plywood made with PF had the dry and wet bonding strength that can fit the standard of CNS1349. When using PO-PF, plywood that hotpressed at 150℃ had the wet bonding strength fit the request too. The values of formaldehyde emission of plywood that made with PF and PO-PF can fit the request of F1 plywood, and that with LL-PF can fit the request of F2 plywood