载药聚丙烯酸/聚乙二醇半互穿聚合物网络在木材中的原位构建及其性能

摘要

【目的】在木材中原位构建载药半互穿聚合物网络体系，以提高木材耐腐性，改善木材的尺寸稳定性。【方法】以丙烯酸为单体，过硫酸铵为引发剂，N，N'－亚甲基双丙烯酰胺为交联剂，在聚乙二醇存在下原位反应，一步法合成聚丙烯酸/聚乙二醇半互穿聚合物网络( PAA/PEG SIPN)。研究交联剂含量对聚合物性能的影响，并采用傅里叶变换红外光谱( FTIR)、扫描电镜( SEM)、透射电镜( TEM)对其结构和形貌进行表征。采用真空浸渍法将质量百分比为0.5%的丙环唑纳米制剂和反应物注入木材中，使其在木材内部进行原位反应并交联，测试处理后木材的尺寸稳定性和室内耐腐性。【结果】FTIR分析表明，PAA 和 PEG 除形成氢键外，还能通过交联剂形成相对牢固的化学结合。SEM 和 TEM 结果发现，聚乙二醇较均匀地分散在聚丙烯酸中，形成相互贯穿的网络结构。在一定范围内，随着交联剂含量的增加，聚合物的溶胀性能减弱，强度增大。相对于未处理材，处理材的干缩湿胀性得到明显改善。室内耐腐性试验表明，处理材的药剂抗流失性和耐腐性得到明显提高。【结论】本文所及处理方法能够在一定程度上提高木材的尺寸稳定性和防腐性能，虽然对尺寸稳定性的作用尚未达到理想状态，但可为木材的改性处理提供一种新思路。%Objective]Decay and cracks are the main factors which shorten the service life of oudoor wood. In this study,drug-loaded semi-interpenetrating network and in situ constructed in wood were investigated,in order to improve the decay resistance as well as the dimensional stability.[Method]Polyacrylate/polyethylene glycol( PAA/PEG) polymer alloy with semi-interpenetrating network ( SIPN ) structure was prepared by one-step polymerization. The relationship between the amount of crosslinker and polymer performance was then studied. The prepared SIPN polymer alloy was characterized by infrared spectroscopy ( IR ) ,scanning electron microscope ( SEM ) and transmission electron microscope ( TEM) . Populus tomentosa wood was impregnated with 0. 5% propiconazole nanoemulsion,acrylic acid,PEG,initiator and crosslinker under vacuum,then in situ polymerized. The dimensional stability and decay resistance properties of wood were also measured. [Result]FTIR results showed that PAA and PEG formed strong H-bond,and the crosslinker might chemically connected them. SEM and TEM indicated that PEG was uniformly dispersed in PAA to form a phase-separate structure. An interpenetrated interface could be observed. Additionally,the dimensional stability tests of wood via three wet-dry cycles showed that the treated wood exhibited minor shrinkage and swelling. The decay resistances of drug-loaded SIPN were greatly improved. [Conclusion]Though the dimensional stability did not meet the expected results,this paper provided a new way to simultaneously improve the dimensional stability and fungi resistances.