摘要
将具有仿生矿化功能的壳聚糖与SiO 2层层自组装,对尾巨桉木材实现仿生物矿化协同改性。在桉木木材细胞壁接枝壳聚糖,与多羟基SiO 2交替接枝实现桉木木材性能改良。对改性的桉木进行顺纹抗压强度、冲击韧性、耐磨性、硬度等力学性能检测和热重分析,并用SEM、FTIR和XRD表征其微观形貌和结构。结果表明:改性桉木的顺纹抗压强度、冲击韧性、耐磨性、端面硬度分别为85.91 MPa、82.5 kJ/m^2、18.30 mg/100r、6450 N,较空白组桉木分别提升54.8%、94.1%、24.8%、110%;热稳定性残炭量达到48.21%,相对桉木提高173%。壳聚糖与SiO 2协同改性桉木,形成了有机-无机杂化结构,增强了木材性能。SEM显示木材内部形成了三维网络有机-无机杂化结构并覆盖纹孔及导管,部分SiO 2粒子呈球状颗粒分布于木材导管壁、木纤维细胞壁之间;XRD测试表明SiO 2粒子以非晶态进入木材,与空白组桉木相比,改性材的衍射峰强度和结晶度都略微减小;经分析壳聚糖与木材形成稳定的-CONH化合键后静电吸附SiO 2粒子,并与之形成Si-O-C键。
The biomimetic mineralization of Eucalyptus urophylla wood was modified by self-assembly of chitosan and SiO2. Chitosan was grafted onto the cell wall of Eucalyptus wood,and polyhydroxyl SiO2 was grafted alternately to improve the wood properties of Eucalyptus. The mechanical properties such as compression strength parallel to grain,impact toughness,abrasion resistance,hardness and thermal stability of modified Eucalyptus were tested. SEM,FTIR and XRD were used to study the microstructure and structure of materials. The results showed that compression strength parallel to grain,impact toughness,wear resistance and end face hardness properties were 85. 91 MPa,82. 5 k J/m2,18. 30 mg/100 r,6 450 N,and increased by 54. 8%,94. 1%,24. 8% and 110% respectively. Thermal stability carbon residue reached 48. 21%,which increased 173% compared with blank Eucalyptus. Chitosan and SiO2 co-modified Eucalyptus can form organic-inorganic hybrid structure to enhance the properties of wood. SEM showed that there was a three-dimensional network of organic and inorganic hybrid structures covering the pores and ducts inside the wood,and some SiO2 particles were distributed between the wood fiber cell walls in the wood duct wall as spherical particles.XRD showed that SiO2 particles enter into wood in amorphous state,compared with blank Eucalyptus,the diffraction peak strength and crystallinity of the modified material decreased slightly. After the formation of stable-CONH bond between chitosan and wood,Si-O-C bond was formed by electrostatic adsorption of SiO2 particles.
作者
陈世尧
袁光明
杨涛
夏名出
牟明明
CHEN Shiyao;YUAN Guangming;YANG Tao;XIA Mingchu;MU Mingming(College of Material Science and Engineering,Central South University of Forestry&Technology,Changsha 410004,China;Collaborative Innovation Center for Effective Utilizing of Wood&Bamboo Resource,Changsha 410004,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2020年第10期10182-10186,共5页
Materials Reports
基金
国家自然科学基金(31770606)
湖南省科技重大专项(2017NK1010)。
关键词
仿生物矿化
壳聚糖
SIO2
杂化结构
桉木改性
biomimetic mineralization
chitosan
SiO2
hybrid structure
Eucalyptus wood modification
