Composites Part A: Applied Science and Manufacturing ( IF 8.7 ) Pub Date : 2018-06-23 , DOI: 10.1016/j.compositesa.2018.06.028 Shu Huang , Zhan Zhao , Chuang Feng , Edwin Mayes , Jie Yang
Carboxylate modified cellulose nanofibril (CNF) was used to reinforce poly(acrylamide-co-acrylic acid) (P(AAm-co-AAc)) hydrogel via in-situ polymerization. With introduction of Fe3+-carboxylate complexation, a dual cross-linking network structure in the P(AAm-co-AAc)/CNF hydrogels was constructed, i.e. the covalently cross-linked acrylic components forming a macromolecular network, and the noncovalently COO−-Fe3+ ionic coordination bonds acting as secondary cross-linking points. The microstructure of the hydrogels was characterized by scanning electron microscopy (SEM). By incorporating 0.6 wt% CNF, the elastic modulus, tensile strength and toughness of P(AAm-co-AAc) hydrogel were improved by 240%, 104% and 51%, respectively. The addition of CNF also enhanced the energy dissipation in loading and unloading tests. P(AAm-co-AAc)/CNF nanocomposite hydrogels showed water content (70–80%) comparable with that in human cartilage (75%). The biocompatibility tests suggested that P(AAm-co-AAc)/CNF had no toxicity to cells and cells can adhere and proliferate well on the surface, making it suitable for biomedical and tissue engineering applications.
中文翻译:
纳米纤维素增强的P(AAm- co -AAc)水凝胶具有改善的机械性能和生物相容性
羧酸盐修饰的纤维素纳米原纤维(CNF)用于通过原位聚合来增强聚(丙烯酰胺-共-丙烯酸)(P(AAm-共-AAc))水凝胶。随着Fe 3+ -羧酸盐络合物的引入,在P(AAm- co -AAc)/ CNF水凝胶中构建了双交联网络结构,即形成大分子网络的共价交联丙烯酸组分和非共价COO - -Fe 3+离子的配位键作为二次交联点。通过扫描电子显微镜(SEM)表征水凝胶的微观结构。通过加入0.6 wt%的CNF,P(AAm- co)的弹性模量,拉伸强度和韧性-AAc)水凝胶分别改善了240%,104%和51%。CNF的添加还增强了装卸测试中的能量耗散。P(AAm- co -AAc)/ CNF纳米复合水凝胶的含水量(70-80%)与人软骨中的含水量(75%)相当。生物相容性测试表明,P(AAm- co -AAc)/ CNF对细胞没有毒性,并且细胞可以在表面粘附并良好增殖,因此非常适合生物医学和组织工程应用。