發泡劑及介面活性劑對液化木材所製造PU發泡體性質之影響

Effects of Blowing Agent and Surfactant on the Properties of PU Foams Made from Liquefied Wood

李文昭(Wen-Jau Lee) ； 張嘉方(Chia-Fang Chang)

《林產工業》 26卷4期 (2007/12) Pp. 287-295

https://doi.org/10.6561/FPI.2007.26(4).5

摘要

本研究利用聚乙二醇／丙三醇混合液為溶劑對杉木及相思樹木材進行液化處理，並將液化木材與異氰酸酯PMDI混合製造PU發泡體，探討發泡劑及界面活性劑添加量對所得PU發泡體性質之影響。由其結果得知在未添加發泡劑條件下，液化木材與PMDI仍有發泡反應發生，然其發泡體為一硬質結構；添加3%水為發泡劑者有助於其發泡成型，但水添加過量時其發泡體之壓縮應力偏低。未添加界面活性劑時液化木材與異氰酸酯間之相容性較差，發泡程度較低，所製造PU發泡體比重較大，泡孔體積不均勻；而添加2%界面活性劑可提高其發泡程度，所得PU發泡體之比重較低，且較為柔軟；提高界面活性劑添加量至10%可使其PU發泡體中氣泡較小，且分布較均勻，並可提高其壓縮應力。

關鍵字

液化木材 ； 異氰酸酯 ； PU發泡體 ； 發泡劑 ； 界面活性劑

並列摘要

In this study, woods of China fir (Cunninghamia lanceolata) and Taiwan acacia (Acacia confusa) were liquefied with the mixture of polyethylene glycol/glycerol as a solvent. The liquefied woods were blended with the isocyanate of PMDI to prepare the polyurethane foams (PU foams). The effects of blowing agent and surfactant on the properties of PU foams were investigated. The results showed that the foaming reaction would take place as the liquefied woods blended with PMDI even without the addition of blowing agent. But the resultant PU foams had a hard structure. Adding 3% of water as the blowing agent could promote the foaming reaction. However, as too much water was added, the compression stress of the PU foams would be decreased. The liquefied wood and isocyanate had poor compatibility as no surfactant existed. The PU foams made without surfactant had a lower degree of foaming and had a higher specific gravity. In addition, those pores appeared in the structure of PU foams had an uneven volume. When 2% of surfactant was added, the foaming reaction could be improved. The PU foams made would have a lower specific gravity and a more soft structure. By increasing the amount of surfactant to 10%, the air bubble in the PU foams became smaller and more uniform, and the compression stress would be increased.

並列關鍵字

Liquefied wood ； Isocyanate ； PU foam ； Blowing agent ； Surfactant