- 期刊
不同原料及製作條件酚醛樹脂發泡體之性質
Properties of Phenol-formaldehyde Resin Foams Prepared by Different Raw Materials and Manufacturing Conditions
摘要
本研究將柳杉（Cryptomeria japonica）木粉及木質素以酚為溶劑進行液化處理，利用化石酚（Petrochemical phenol; P）、酚液化木材（Liquefied wood; LW）、酚液化木質素（Liquefied lignin; LL）分別與福馬林反應製備PF、LW-PF及LL-PF酚醛樹脂（Phenol-formaldehyde Resins; PF）。DSC分析顯示三種PF樹脂在熱掃描過程有相似之熱硬化行為，然其中以PF樹脂有較大的架橋反應放熱峰高度及面積。進一步以上述三種樹脂為基質，並添加異丙醚為發泡劑，Tween 80為界面活性劑，HCl為硬化劑（4%、6%、8%、10%），於不同溫度（30℃、60℃、80℃）使發泡成型製作發泡體。結果顯示提高硬化劑添加量或反應環境溫度有助樹脂之發泡作用，所形成泡孔屬於密閉型孔壁。發泡體之壓縮強度主要受發泡體之密度所影響。不同樹脂比較，在相同製作條件下，PF樹脂有較佳之發泡效果及發泡體強度，LW-PF樹脂次之，LL-PF樹脂則較低。TGA分析顯示PF樹脂發泡體有較佳之熱抵抗性，加熱成型發泡體之熱抵抗性優於常溫發泡者。
並列摘要
In this study, wood powders of Cryptomeria japonica and lignin were liquefied with phenol as a solvent. Phenol (P), liquefied wood (LW), and liquefied lignin (LL) were reacted with formalin, respectively, in order to prepare phenol-formaldehyde resins (PF). The DSC analysis shows that all PF resins had a similarity of thermo-setting behavior during heat scanning process. However, the PF resin had the exothermic peak with a larger height and area than others. Furthermore, the foams were prepared by using PF resins as base materials and diisopropyl ether as foaming agent, Tween 80, and HCl (4%, 6%, 8%, 10%) as surfactant and hardener, respectively, and prepared under different temperatures (30oC, 60oC and 80oC). The results show that the foaming reaction advanced by increasing the dosages of catalyst and the foaming temperature. All foams belonged to closed-cell foams. The compressive strength of foams mainly depended on the density of foams. Comparisons among different resins under the same manufacturing conditions show that foams made with PF resin had better foaming effect and higher strength, followed by LW-PF, and LL-PF. The TGA analysis showed that the foams made from PF resin had better thermal resistance than others. Foams made under heating condition had better thermal resistance than that made at room temperature.