Chandrasekaran Saravanan, Castaing Remi, Cruz-Izquierdo Alvaro, Scott Janet L
Centre for Sustainable Chemical Technologies, Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
Department of Chemistry, School of Engineering, Presidency University, Rajanukunte, Itgalpura, Bangalore 560064, India.
Nanomaterials (Basel). 2021 Jun 4;11(6):1488. doi: 10.3390/nano11061488.
Thin films of cellulose and cellulose-CaSiO composites were prepared using 1-ethyl-3-methylimidazolium acetate (EMIMAc) as the dissolution medium and the composites were regenerated from an anti-solvent. The surface hydrophilicity of the resultant cellulose composites was lowered by coating them with three different hydrophobizing agents, specifically, trichloro(octadecyl)silane (TOS), ethyl 2-cyanoacrylate (E2CA) and octadecylphosphonic acid (ODPA), using a simple dip-coating technique. The prepared materials were subjected to flame retardancy, water barrier, thermal, mechanical and biodegradation properties analyses. The addition of CaSiO into the cellulose increased the degradation temperature and flame retardant properties of the cellulose. The water barrier property of cellulose-CaSiO composites under long term water exposure completely depends on the nature of the hydrophobic agents used for the surface modification process. All of the cellulose composites behaved mechanically as a pure elastic material with a glassy state from room temperature to 250 °C, and from 20% to 70% relative humidity (RH). The presence of the CaSiO filler had no effect on the elastic modulus, but it seemed to increase after the TOS surface treatment. Biodegradability of the cellulose was evaluated by enzyme treatments and the influence of CaSiO and hydrophobic agents was also derived.
以1-乙基-3-甲基咪唑醋酸盐（EMIMAc）作为溶解介质制备了纤维素和纤维素-CaSiO复合材料薄膜，并通过反溶剂使复合材料再生。通过使用简单的浸涂技术，用三种不同的疏水化剂，即三氯（十八烷基）硅烷（TOS）、氰基丙烯酸乙酯（E2CA）和十八烷基膦酸（ODPA）对所得纤维素复合材料进行涂层处理，降低了其表面亲水性。对制备的材料进行了阻燃性、防水性、热性能、机械性能和生物降解性能分析。向纤维素中添加CaSiO提高了纤维素的降解温度和阻燃性能。纤维素-CaSiO复合材料在长期水暴露下的防水性能完全取决于用于表面改性过程的疏水剂的性质。在室温至250℃以及20%至70%相对湿度（RH）范围内，所有纤维素复合材料在机械性能上都表现为纯弹性材料且处于玻璃态。CaSiO填料的存在对弹性模量没有影响，但在TOS表面处理后弹性模量似乎有所增加。通过酶处理评估了纤维素的生物降解性，并得出了CaSiO和疏水化剂的影响。
