Department of Chemical Engineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
Sci Rep. 2022 Aug 30;12(1):14724. doi: 10.1038/s41598-022-17437-z.
This present study demonstrated the preparation of a highly crystalline anatase (ana) form of titanium oxide (TiO) doped silk nanocrystal (SNC) nanohybrid (ana-TCS) of diameter (7.5 ± 1.4 nm) by the sol-gel method using titanium (IV) butoxide as the hydrolysis material. This prepared nanohybrid with surface hydroxyl groups acted as a co-initiator for the synthesis of poly(L-lactic acid) (PLLA)-g-ana-TSC nanocomposite with grafted PLLA chains via the in situ polymerization technique, using tin-octoate as a catalyst. The fabricated nanocomposite had a high number average molecular weight of 83 kDa with good processibility. This prepared nanocomposite was hydrophobic in nature, with a contact angle of 105°, which was further enhanced to 122 ± 1° when processed via electrospinning technique into a non-woven fabric. The prepared nanocomposite could degrade up to 43% methylene blue dye in 15 days. This nanocomposite showed no significant molecular weight reduction after 1 h of aqeous treatment, which could be attributed to its hydrophobic nature, inhibiting its degradation. However, 50% degradation was observed for the nanocomoposite whereas, PLLA demonstrated 25% degradation in 15 days, after its end-of-life. Thus, this study revealed that the in situ synthesized PLA-ana-TCS nanocomposite could be targeted for use as a hydrophobic, self-cleaning, dye-degradable fabric.
本研究通过溶胶-凝胶法，以钛（IV）丁氧基为水解材料，制备了一种具有高度结晶性锐钛矿（ana）形态的二氧化钛（TiO）掺杂丝纳米晶（SNC）纳米杂化物（ana-TCS），其直径为（7.5±1.4）nm。这种具有表面羟基的纳米杂化物作为共引发剂，通过原位聚合技术，使用辛酸亚锡作为催化剂，合成了接枝有聚（L-乳酸）（PLLA）链的 PLLA-ana-TSC 纳米复合材料。所制备的纳米复合材料具有高数均分子量 83 kDa，具有良好的加工性能。该纳米复合材料为疏水性，接触角为 105°，通过静电纺丝技术加工成非织造布后进一步提高至 122±1°。该纳米复合材料在 15 天内可降解高达 43%的亚甲基蓝染料。该纳米复合材料在 1 小时的水性处理后没有明显的分子量降低，这可能归因于其疏水性，抑制了其降解。然而，在 15 天内，纳米复合材料的降解率为 50%，而 PLLA 的降解率为 25%，在其使用寿命结束后。因此，本研究表明，原位合成的 PLA-ana-TCS 纳米复合材料可作为一种疏水性、自清洁、可降解染料的织物。
