Department of Forest Products Technology, School of Chemical Technology, Aalto University, P.O. Box 16300, FI-0076 Aalto, Finland.
Process Chemistry Centre, c/o Laboratory of Wood and Paper Chemistry, Åbo Akademi University, Porthansgatan 3, FI-20500 Åbo/Turku, Finland.
Carbohydr Polym. 2014 Sep 22;110:163-72. doi: 10.1016/j.carbpol.2014.03.087. Epub 2014 Apr 4.
Nanofibrillated cellulose (NFC) and hemicelluloses have shown to be highly promising renewable components both as barrier materials and in novel biocomposites. However, the hydrophilic nature of these materials restricts their use in some applications. In this work, the usability of modified O-acetyl galactoglucomannan (GGM) for modification of NFC surface properties was studied. Four GGM-block-structured, amphiphilic derivatives were synthesized using either fatty acids or polydimethylsiloxane as hydrophobic tails. The adsorption of these GGM derivatives was consecutively examined in aqueous solution using a quartz crystal microbalance with dissipation monitoring (QCM-D). It was found that the hydrophobic tails did not hinder adsorption of the GGM derivatives to cellulose, which was concluded to be due to the presence of the native GGM-block with high affinity to cellulose. The layer properties of the adsorbed block-co-polymers were discussed and evaluated. Self-standing NFC films were further prepared and coated with the GGM derivatives and the effect of the surface modification on wetting properties and oxygen permeability (OP) of the modified films was assessed.
纳米原纤化纤维素 (NFC) 和半纤维素已被证明是极具前景的可再生成分，可作为阻隔材料和新型生物复合材料使用。然而，这些材料的亲水性限制了它们在某些应用中的使用。在这项工作中，研究了改性 O-乙酰基半乳甘露聚糖 (GGM) 对 NFC 表面性能改性的适用性。使用脂肪酸或聚二甲基硅氧烷作为疏水尾，合成了四种具有 GGM 嵌段结构的两亲性衍生物。使用石英晶体微天平（QCM-D）连续监测在水溶液中这些 GGM 衍生物的吸附情况。结果发现，疏水尾并没有阻碍 GGM 衍生物吸附到纤维素上，这是由于存在与纤维素具有高亲和力的天然 GGM 嵌段。讨论并评估了吸附的嵌段共聚物的层性质。进一步制备了自支撑 NFC 薄膜，并将 GGM 衍生物涂覆在薄膜上，评估了表面改性对改性薄膜润湿性和氧气透过率 (OP) 的影响。
