中文摘要：

通过一次性超细研磨方法得到纳米纤维素（CNF）,其直径分布均匀,大小为15 nm,且长径比大于10 000,呈三维网状结构,成膜后呈高强度（210 MPa）、高模量（11.8 GPa）.将上述CNF与聚乙烯醇（PVA）在一定条件下混溶后制得CNF/PVA复合材料.通过场发射扫描电镜和静态热机械分析等手段研究了复合材料的形貌特征、热膨胀性及力学性能.扫描电镜测试结果表明,CNF与PVA混溶均匀,相互缠绕在一起形成互穿三维网状结构.与纯PVA比较,CNF/PVA复合材料的热膨胀系数（45×10-6K-1）降低了30％,拉伸强度（110 MPa）提高了45％,杨氏模量（6.6 GPa）提高了50％.

英文摘要：

Cellulose nanofiber （CNF） was obtained by using only one pass through the grinder treatment, which had a uniform width of 15 nm. It also showed three-dimensional network structure and high aspect ratio （ 〉 10 000）. The dry CNF film exhibited high strength （210 MPa） and high modulus （11.8 GPa）. CNF/PVA composite were prepared by mixing CNF suspension and PVA aqueous solution. The morphology feature, thermal expansion and mechanical properties of CNF/PVA composite was characterized by feld emission scanning electron microscopy and static thermo-mechanieal analysis. SEM showed that CNF and PVA mixed very uniformly, they entangled and interpenetrated with each other and formed three-dimensional network structure. The coefficient of thermal expansions （45 x 10 -6 K ^-1 ） of CNF/PVA was decreased by 30%, the tensile strength （ll0 MPa） was increased by 45%and the Young＇s modulus （6. 6 GPa） was increased by 50%.