Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center of Eco-material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; School of Materials Science and Engineering, Lanzhou Jiaotong University, Lanzhou 730070, PR China.
School of Materials Science and Engineering, Lanzhou Jiaotong University, Lanzhou 730070, PR China.
Int J Biol Macromol. 2020 Aug 1;156:1297-1307. doi: 10.1016/j.ijbiomac.2019.11.168. Epub 2019 Nov 21.
Biopolymers have shown great application prospects due to their advantages of being biodegradable, renewable, non-toxic, safe and inexpensive. However, the innate hydrophilicity of biopolymers means the materials prepared from them easily swell or disintegrate in aqueous media, limiting their applications. Herein, on the basis of improving the mechanical performance of a sodium alginate/poly(vinyl alcohol) (SA/PVA) film by introducing palygorskite (Pal) nanorods, the hydrophobicity of the obtained SA/PVA/Pal film was improved further by surface coating with methyltrichlorosilane (MTCS) through a vapor deposition-surface polycondensation reaction. MTCS nanofilaments, with a size of approximately 50 nm, were formed on the film surface by the silanization reaction between MTCS and hydroxyls, resulting in an improvement in surface hydrophobicity characterized by a contact angle (111.8°) higher than that of SA/PVA/Pal film (72.7°). Therefore, the obtained films maintained their original shape and strength after soaking for a long time in aqueous solutions containing acid, alkaline, and electrolyte, also in organics, while the uncoated film dissolved quickly and lost its original shape. Moreover, the surface coating also increased the film's tensile strength from 11.43 to 28.69 MPa. This demonstrates a simple, universal and effective way to improve the resistance of biopolymer-derived materials to water and various chemicals.
生物聚合物具有可生物降解、可再生、无毒、安全且廉价等优点，因此具有广阔的应用前景。然而，生物聚合物的固有亲水性意味着由它们制备的材料在水介质中容易溶胀或分解，从而限制了它们的应用。在此，通过引入凹凸棒石纳米棒（Pal）来提高海藻酸钠/聚乙烯醇（SA/PVA）膜的机械性能的基础上，通过气相沉积-表面缩聚反应，用甲基三氯硅烷（MTCS）对所得的 SA/PVA/Pal 膜进行表面涂覆，进一步提高其疏水性。MTCS 纳米纤维通过 MTCS 与羟基之间的硅烷化反应形成，尺寸约为 50nm，在膜表面形成，导致接触角（111.8°）高于 SA/PVA/Pal 膜（72.7°），表现出疏水性的提高。因此，所得的膜在长时间浸泡在含有酸、碱和电解质的水溶液以及有机溶剂中后仍保持其原始形状和强度，而未涂层的膜则迅速溶解并失去其原始形状。此外，表面涂层还将膜的拉伸强度从 11.43MPa 提高到 28.69MPa。这证明了一种简单、通用且有效的方法来提高生物聚合物衍生材料对水和各种化学物质的抵抗力。
