不同纤维原料对羧乙基微纤化纤维素膜性能的影响

Effect of Different Fiber Raw Materials on the Properties of Carboxyethyl Microfibrillarized Cellulose Films

关键词:  羧基含量  研磨程度  原料种类  羧乙基微纤化纤维素膜  抗张强度

Key Words:carboxyl content  grinding degree  type of raw materials  carboxyethyl microfibrillarized cellulose films  physical properties

摘要:采用6种不同的纤维原料（漂白硫酸盐阔叶木浆、漂白硫酸盐竹浆、漂白硫酸盐针叶木浆、棉短绒浆、漂白针叶木化学机械浆和玉米芯纤维素）经羧乙基化预处理和机械研磨制备了微纤化纤维素（Microfibrillarized cellulose，MFC），并通过涂布法制备了MFC膜。探讨了原料羧基含量、研磨程度和原料种类对MFC及其膜性能的影响。结果表明，随着预处理后漂白硫酸盐阔叶木浆羧基含量的增加，MFC的保水值由98%增加到538%，MFC膜的孔隙率由37%下降至19%。当羧基含量为0.8 mmol/g时，MFC膜的抗张强度最高，达53 MPa。另外，随着研磨程度（次数）的增加，所得MFC纤丝化程度提高，MFC膜的强度先升高后降低，最高值为75 MPa。在最优的羧乙基化预处理条件和研磨程度下，由6种不同纤维原料制备的MFC膜中，漂白硫酸盐竹浆所得MFC膜的强度最高，为84 MPa，其孔隙率为25%。

Abstract:Microfibrillarized cellulose (MFC) was prepared from six different fiber raw materials (including hardwood bleached kraft pulp, bamboo bleached kraft pulp, softwood bleached kraft pulp, cotton linter pulp, softwood bleached chemimechanical pulp, and corncob cellulose) by carboxyethylation pretreatment combined with mechanical grinding, and then MFC films were formed by rod coating method. The effects of carboxyl content, grinding times and type of raw materials on the properties of MFC and its films were discussed. The results showed that the water retention value of MFC increased from 98% to 538% and the porosity of MFC film decreased from 37% to 19% with the increase of carboxyl content in the pretreated hardwood bleached kraft pulp. When the carboxyl content was 0.8 mmol/g, the tensile strength of MFC film was the highest, reaching 53 MPa. In addition, with the increase of grinding times, the degree of fibrillation of MFC increased, and the strength of MFC film increased first and seached a maximum value of 75 MPa then decreased. Under the optimum conditions of carboxyethylation pretreatment and grinding times, among the MFC membranes prepared from six different raw materials, the strength of MFC membranes obtained from bleached bamboo kraft pulp was the highest, up to 84 MPa, with a porosity of 25%.