Learning Institute, King Mongkut's University of Technology Thonburi, Bangkok, 10140, Thailand.
Cellulose and Bio-Based Nanomaterials Research Group, King Mongkut's University of Technology Thonburi, Bangkok, 10140, Thailand.
Sci Rep. 2022 May 26;12(1):8920. doi: 10.1038/s41598-022-12688-2.
Cellulose, the most abundant biopolymer on Earth, has been widely attracted owing to availability, intoxicity, and biodegradability. Environmentally friendly hydrogels were successfully prepared from water hyacinth-extracted cellulose using a dissolution approach with sodium hydroxide and urea, and sodium tetraborate decahydrate (borax) was used to generate cross-linking between hydroxyl groups of cellulose chains. The incorporation of borax could provide the superabsorbent feature into the cellulose hydrogels. The uncross-linked cellulose hydrogels had a swelling ratio of 325%, while the swelling ratio of the cross-linked hydrogels could achieve ~ 900%. With increasing borax concentrations, gel fraction of the cross-linked hydrogels increased considerably. Borax also formed char on cellulose surfaces and generated water with direct contact with flame, resulting in flame ignition and propagation delay. Moreover, the cross-linked cellulose-based hydrogels showed antibacterial activity for gram-positive bacteria (S. aureus). The superabsorbent cross-linked cellulose-based hydrogels prepared in this work could possibly be used for wound dressing, agricultural, and flame retardant coating applications.
纤维素是地球上最丰富的生物聚合物，由于其可用性、低毒性和可生物降解性而受到广泛关注。本研究采用氢氧化钠和尿素的溶解方法，从水葫芦中提取纤维素，成功制备了环境友好型水凝胶，四硼酸钠十水合物（硼砂）用于在纤维素链羟基之间产生交联。硼砂的掺入可以为纤维素水凝胶提供高吸水性。未交联的纤维素水凝胶的溶胀比为 325%，而交联水凝胶的溶胀比可达到~900%。随着硼砂浓度的增加，交联水凝胶的凝胶分数显著增加。硼砂还在纤维素表面形成炭，并与火焰直接接触产生水，导致火焰点火和传播延迟。此外，交联的基于纤维素的水凝胶对革兰氏阳性菌（金黄色葡萄球菌）表现出抗菌活性。本工作中制备的高吸水性交联纤维素基水凝胶可能可用于伤口敷料、农业和阻燃涂层应用。
