不同末端基聚胺基甲酸酯樹脂之性質

The Properties of Polyurethane Resins with Different Terminated Groups

楊彝綱(Yi-Gang Yang) ； 陳奕君(Yi-Chun Chen) ； 李文昭(Wen-Jau Lee)

《林產工業》 35卷3期 (2016/09) Pp. 153-162

https://doi.org/10.6561/FPI.2016.35(3).4

摘要

本研究將柳杉（Cryptomeria japonica Don；Japanese cedar）木粉以聚乙二醇（Polyethylene glycol；PEG）/丙三醇混合液為溶劑進行液化處理。進一步以PEG及PEG/液化木材（Liquefied wood；LW）（65/35；wt/wt）為多元醇原料，異氟爾酮二異氰酸酯（Isophorone diisocyanate）為異氰酸酯原料，乙二胺（Ethylenediamine；EDA）及1,4-丁二醇（1,4-Butanediol；1,4-BD）為鏈延長劑合成末端為NCO基、NH基及OH基之聚胺基甲酸酯樹脂（Polyurethane resins；PU），並探討不同種類多元醇及不同末端基結構對PU樹脂之分子量、分子結構、物理機械性質及熱性質之影響。由結果得知，在異氰酸酯與PEG多元醇之NCO/OH莫耳比1.6/1條件下反應所得PU樹脂含NCO末端基（代號NCO-PU），經添加EDA及1,4-BD進行鏈延長反應所得末端為胺基及羥基之NH-PU及OH-PU之NCO基消失，分子量則大幅增加。DSC分析結果顯示NCO-PU在熱掃描過程出現架橋反應之放熱峰，OH-PU及NH-PU則出現吸熱現象，其中NH-PU分子鏈之熱活動性大於OH-PU。DMA分析結果顯示NH-PU及OH-PU在加熱過程均出現相轉移現象，其阻尼值曲線出現單一波峰，而含LW之NH-LWPU及OH-LWPU則出現兩個阻尼值波峰，顯示此樹脂內部存在不均質之分子結構。TGA分析結果顯示不同製備條件PU樹脂有相似之熱裂解行為，其熱裂解主要發生在250~350°C。添加LW可提高PU樹脂之熱抵抗性。

關鍵字

鏈延長劑 ； 柳杉 ； 液化木材 ； 聚胺基甲酸酯樹脂 ； 末端基

並列摘要

In this study, wood powders of Cryptomeria japonica Don (Japanese cedar) were liquefied with the mixture of polyethylene glycol (PEG) and glycerol as the solvent. Polyurethane resins (PU) with NCO-, NH-, and OH-terminated were prepared by using PEG and PEG/liquefied wood (LW), isophorone diisocyanate, ethylenediamine (EDA) and 1,4-butanediol (1,4-BD) as raw materials of polyols, isocyanate and chain extenders, respectively. The effects of the kind of polyols and the difference of terminated groups on the molecular weight, molecular structure, physicomechanical properties and thermal properties of PU resins were investigated. The experimental results showed that PU resin obtained by reacting isocyanate with polyol with the NCO/OH molar ratio of 1.6/1 had the NCO-terminated group (NCO-PU). The NCO groups disappeared and the molecular weight substantially increased for NH-PU and OH-PU that underwent the chain extension reaction by adding EDA and 1,4-BD, respectively. The experimental results of DSC analysis showed that an exothermic peak due to the crosslinking reaction appeared for NCO-PU during the heat scanning. Nevertheless, an endothermic phenomenon appeared for OH-PU and NH-PU. Among them, the thermal activity of molecular chain for NH-PU was higher than that for OH-PU. DMA results showed that a phase transition phenomenon occurred for both NH-PU and OH-PU in the heating process and a single peak appeared in the damping value curve. However, two damping value peaks were found for LW-containing NH-LWPU and OH-LWPU, indicating a nonuniform molecular structure existed within these PU resins. TGA results showed that PU resins prepared under different conditions had similar thermal degradation behavior, and the main thermal degradation occurred at the temperature between 250°C and 350°C. The heat-resistance of PU resins could be increased by adding LW.

並列關鍵字

Chain extender ； Cryptomeria japonica ； Liquefied wood ； Polyurethane resins ； Terminated groups