SiO_(2)气凝胶纳米颗粒浸渍改性对竹材性能的影响  

Effect of SiO_(2) aerogel nanoparticles impregnation on properties of bamboo

作　　者：邹艳萍 王献轲 张雨湉 费本华 陈红 ZOU Yanping;WANG Xianke;ZHANG Yutian;FEI Benhua;CHEN Hong(College of Furnishings and Industrial Design,Nanjing Forestry University,Nanjing 210037,China;International Center for Bamboo and Rattan,Beijing 100102,China)

机构地区：[1]南京林业大学家居与工业设计学院,南京210037 [2]国际竹藤中心,北京100102

出　　处：《林业工程学报》2022年第4期46-51,共6页Journal of Forestry Engineering

基　　金：国家自然科学基金(31500474)。

摘　　要：竹材作为我国第二大森林资源,在许多领域可以替代木材使用,但竹材的亲水性会带来尺寸稳定性差、易霉变等问题,极大地限制了其大规模的推广与应用。利用二氧化硅(SiO_(2))气凝胶纳米材料真空浸渍处理竹材,并在浸渍液中添加分散剂聚乙烯醇(PVA),浸渍时间分别为3和9 h,以及3 h循环浸渍3次。采用冷场发射扫描电子显微镜(SEM)、接触角测试仪和万能力学试验机对不同工艺参数处理竹材的浸渍效果、疏水性和抗弯性能进行表征,并对竹材的尺寸稳定性及防霉效果进行测试。从竹材表面的SEM和能谱图中可以看出,随着浸渍次数和浸渍时间的增加,SiO_(2)气凝胶纳米颗粒的附着量逐渐增多,且在浸渍超过3 h时有大块堆积现象,说明PVA在一定程度上提高了SiO_(2)气凝胶纳米材料在竹材上的附着力;从竹材内部横截面的SEM和能谱图中可以看出,随着浸渍次数和浸渍时间的增加,竹材内部横截面的SiO_(2)气凝胶附着量及Si元素也随之增加,说明SiO_(2)气凝胶纳米颗粒成功进入了竹材的内部,且附着量随着浸渍时间的延长而增加。浸渍9 h时表面水接触角最大,可达147°;添加PVA浸渍3次循环时端面水接触角最大,可达133°,与未处理竹材相比疏水性显著提高。浸渍处理后竹材抗弯强度和弹性模量均有所下降;抗弯强度在浸渍3次循环时下降幅度最大,下降了26.9%;弹性模量在添加PVA浸渍3次循环时下降幅度最大,下降了22.1%。气干湿胀率在浸渍9 h时最低,为1.8%;饱水湿涨率在浸渍3次循环时最低,为5.41%。竹材的防霉效果也有一定的提升,在添加PVA浸渍3次循环时效果最好。经过SiO_(2)气凝胶浸渍后的竹材疏水性明显提升,简单便捷的SiO_(2)气凝胶浸渍改性制备疏水竹材有望扩展竹材的应用领域。As the second largest forest resource in China, bamboo can be used as a substitute for wood in many fields. However, the hydrophilic nature of bamboo brings about problems such as poor dimensional stability and easy to mold, which greatly limit its large-scale production and application. In this study, vacuum impregnation of silica(SiO_(2)) aerogels nanomaterials was used to impregnate bamboo samples, and polyvinyl alcohol(PVA) was added into the impregnation solution as a dispersant. The impregnation time was 3 or 9 h, in which, 3 h repeated three times. The cold field emission scanning electron microscope(SEM), contact angle tester and mechanical testing machine were used to evaluate the impregnation effect, hydrophobicity and bending strength of the bamboo treated with different process parameters, respectively. The dimensional stability and anti-mold effect of the bamboo were also examined. From the SEM and energy spectra of the surface of treated bamboo, it can be seen that, with the increase of impregnation time and cycles, the amount of silica aerogel nanoparticles increased gradually, and the bulk accumulation occurred when impregnation was over 3 h. The adhesion of silica aerogel powder was improved by the addition of PVA. From the SEM and energy spectra of the internal cross-section of treated bamboo samples, it can be seen that with the increase of impregnation time and cycle, the amount of silica aerogel nanoparticles and Si element in the internal cross-section of bamboo also increased. It was indicated that the silica aerogel nanoparticles successfully entered the core of the bamboo sample and increased with the increase of the impregnation time. The surface water contact angle reached 147° after 9 h of impregnation and reached 133° after three cycles of impregnation with PVA, which was significantly higher than that of the untreated bamboo. After the impregnation treatment, the bending strength and modulus of elasticity of the bamboo material decreased. The bending strength decreased by 26.9% aft

关 键 词：竹材 二氧化硅气凝胶 疏水性 尺寸稳定性 防霉性能 力学性能 

分 类 号：S781.9[农业科学—木材科学与技术]