用户名: 密码: 验证码:
Tuning the Tensile Strength of Cellulose through Vapor-Phase Metalation
详细信息    查看全文
文摘
The infiltration of transition metals into biopolymers by means of vapor-phase processes has been shown to unusually change the bulk mechanical properties of those materials. Here, for the first time, a novel, single precursor infiltration process was applied to cellulose. The mechanical properties, as measured through uniaxial tensile testing, showed improvement as a function of the total number of infiltration cycles as well as the precursor used. For cellulose infiltrated with diethyl zinc with only four infiltration cycles, the ultimate tensile strength was seen to nearly double from 鈭?60 to 鈭?60 MPa. A significant increase was also seen in the elastic modulus, with values increasing 鈭?.5脳, from 鈭?.8 to 鈭?.5 GPa. In contrast, cellulose infiltrated with trimethyl aluminum showed very little improvement in mechanical properties. By choosing the appropriate precursor and/or number of cycles, the mechanical properties become tunable. The chemical changes in the cellulose structure were measured with Raman spectroscopy and a novel semi in situ X-ray photoelectron spectroscopy experiment. The results of both spectroscopic techniques were used to propose a reaction scheme.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700