PVAL/纳米纤维素复合膜的制备及丝光处理对其性能的影响  

Preparation of Composite Film of PVAL/CNF and Effect of Mercerization on Its Properties

作　　者：王海莹[1] 李大纲[1] 

机构地区：[1]南京林业大学材料科学与工程学院,南京210037

出　　处：《工程塑料应用》2014年第3期13-16,共4页Engineering Plastics Application

基　　金：国家自然科学基金项目(31170514;31370557);博士生导师基金(2011320411011);江苏省高校优势学科项目(PAPD)

摘　　要：利用超细研磨机仅一次性研磨的方法制得直径均匀分布在15 nm,长度达几微米的高长径比的纳米纤维素(CNF),经过滤得CNF膜(CNF–I膜),经碱液丝光处理制得CNF–II膜。用浸渍法与聚乙烯醇(PVAL)溶液复合,制得PVAL/CNF–I和PVAL/CNF–II复合膜。对CNF–I和CNF–II膜与PVAL/CNF复合膜的形貌特征、力学性能及热膨胀性进行了表征,研究丝光处理对CNF膜与PVAL/CNF复合膜性能的影响。场发射扫描电镜照片表明,CNF具有独特的互穿三维网状结构,且分布非常均匀;与PVAL复合后,两者界面相容性好,结合致密。拉伸试验分析说明PVAL/CNF–I复合膜的拉伸强度和拉伸弹性模量均大大提高,是纯PVAL膜的2倍左右;经丝光处理后,PVAL/CNF–II复合膜的断裂伸长率提高了一倍,表明其韧性比PVAL/CNF–I复合膜大大提高。静态热机械分析表明:PVAL/CNF–I复合膜的热膨胀系数(CTE)降低到20.5×10-6 K-1,与铝合金的CTE相近,尺寸稳定性大大提高,拓宽了其加工和应用领域。Cellulose nanofiber （CNF） having a uniform width of 15 nm and a length of several micrometers corresponding to a high aspect ratio was successfully obtained by using only one pass through the grinder treatment. CNF film （CNF-I film） was prepared by filtration, and CNF-II film was prepared by further mercerization. After making PVAL / CNF-I and PVAL / CNF-II composite film by impregnation with PVAL solution, the morphology feature, mechanical performance and thermal expansion property of CNF-I, CNF-II film and PVAL / CNF composite film were characterized. The impact of mercerization on properties of CNF film and PVAL / CNF composite film was studied. Field emission scanning electron microscopy observations show that obtained CNF has unique web-like entangled structure with a uniform distribution and is densely combined with PVAL, showing good interfacial bonding between CNF and PVAL. The tensile test explain that the tensile strength and Young＇ s modulus of PVAL / CNF-I composite film is greatly improved, which is about twice as high as pure PVAL film. After mercerization, the elongation at break of PVAL / CNF-II composite film is twice as high as that of PVAL / CNF-I composite film, showing higher toughness. Thermomechanical analysis reveal that the coefficient of thermal expansions （CTE） of PVAL / CNF-I composite film is decreased to 20.5×10-6K-1, which is similar to the CTE of aluminum, corresponding to better dimensional stability, which could broaden its processing and applications field.

关 键 词：丝光处理 超细研磨 纳米纤维素 聚乙烯醇 韧性 静态热机械分析 

分 类 号：TQ325.9[化学工程—合成树脂塑料工业]