PEG400复配ε-己内酯在樟子松饱水木材脱水定型中的应用研究

摘要

The 50% PEG400 aqueous and a hybrid solution of PEG 400 ( 50%) and ε-caprolactone (ε-CL ) ( 50%) were separately used to investigate the dehydration and reinforcement of waterlogged scotch pine wood simulating the archaeological waterlogged wood.The dehydration process included catalyst pre-treatment, impregnation under room temperature and 50 ℃hot dry aggregate .And the weight and dimensional changes of the different stages were analyzed , which was applied to evaluated the effects of process on the dimensional stability , weight gain percentage and reversibility of wood .And then the treated wood was characterized by FT-IR, TGA-DTA and SEM.The results showed that the PEG400 and the hybrid solution of PEG400 andε-CL both had good dehydration and reinforcement effect on waterlogged scotch pine wood with good reversibility .The weight gain percentage of the wood samples treated by the hybrid solution of PEG 400 and ε-CL increased obviously and the value of was 124.1%.After the dehydration and reinforcement , the shrinkages of tangential direction , radial direction and volume were 0.01%、0 and 0.01%,respectively, indicating of the dimensional stability .The ring opening polymerization (ROP) of CL was carried out inside the wood structures to form polycaprolactone ( PCL).The wood cell walls were coated and filled by PCL and PEG400, resulting in the increased thickness of the cell wall .However, the thermostability of wood filled with PLC and PEG 400 was turned to decrease .PLC would firstly degrade at 150 ℃to protect the cell wall of wood .%以人工速生材樟子松为原料,通过热水蒸煮法模拟饱水木材试件,选择50%PEG400水溶液和50%PEG400/50%ε-己内酯(ε-CL)复配溶液用于樟子松饱水木材试件的脱水定型研究.通过催化剂预浸渍、常温置换脱水和50℃热干燥聚合工艺,对比研究了PEG400和PEG400复配ε-CL对樟子松饱水试件的脱水定型效果,分析了各个阶段的质量和尺寸变化,探讨了脱水定型工艺对木材的尺寸稳定性、质量增加率、可逆性的影响;并对脱水定型后的木材试件进行红外光谱(FT-IR)、热重-差热联用(TGA-DTA)、扫描电子显微镜(SEM)分析表征.结果表明:PEG400及PEG400复配ε-CL溶液对樟子松饱水木材试件脱水定型效果良好,均表现出良好的可逆性,PEG400复配ε-CL脱水定型处理的木材试件质量增加明显,脱水定型试件干质量增加率为124.1%,干燥定型过程弦向、径向和体积收缩率分别为0.01%、0和0.01%,表现出良好的尺寸稳定性;FT-IR、TGA-DTA和SEM分析表明,ε-CL单体在木材内部发生开环聚合反应形成聚己内酯(PCL),PCL与PEG400包覆木材细胞壁,填充于木材内部结构中,加固木材细胞壁结构;PCL与PEG400的填充作用导致木材热稳定性降低,PCL于150℃最先发生降解,保护木材细胞壁成分.