Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.
Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; Centre for Sustainable Chemical Technologies, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.
Carbohydr Polym. 2020 Apr 1;233:115816. doi: 10.1016/j.carbpol.2019.115816. Epub 2019 Dec 31.
Rheological properties of hydrogels composed of TEMPO-oxidised cellulose nanofibrils (OCNF)-starch in the presence of cationic surfactants were investigated. The cationic surfactants dodecyltrimethylammonium bromide (DTAB) and cetyltrimethylammonium bromide (CTAB) were used to trigger gelation of OCNF at around 5 mM surfactant. As OCNF and DTAB/CTAB are oppositely charged, an electrostatic attraction is suggested to explain the gelation mechanism. OCNF (1 wt%) and soluble starch (0.5 and 1 wt%) were blended to prepare hydrogels, where the addition of starch to the OCNF resulted in a higher storage modulus. Starch polymers were suggested to form networks with cellulose nanofibrils. The stiffness and viscosity of OCNF-Starch hydrogels were enhanced further by the addition of cationic surfactants (5 mM of DTAB/CTAB). ζ -potential and amylose-iodine complex analyses were also conducted to confirm surface charge and interaction of OCNF-starch-surfactant in order to provide an in-depth understanding of the surfactant-induced gel networks.
研究了在阳离子表面活性剂存在下，由 TEMPO 氧化的纤维素纳米纤维（OCNF）-淀粉组成的水凝胶的流变性。使用阳离子表面活性剂十二烷基三甲基溴化铵（DTAB）和十六烷基三甲基溴化铵（CTAB）来触发 OCNF 在约 5mM 表面活性剂下的胶凝。由于 OCNF 和 DTAB/CTAB 带相反电荷，因此建议静电吸引来解释胶凝机制。将 OCNF（1wt%）和可溶性淀粉（0.5 和 1wt%）混合制备水凝胶，其中向 OCNF 中添加淀粉会导致储能模量增加。淀粉聚合物与纤维素纳米纤维形成网络。通过添加阳离子表面活性剂（5mM 的 DTAB/CTAB）进一步增强了 OCNF-淀粉水凝胶的刚性和粘度。还进行了 ζ-电位和直链淀粉-碘络合物分析，以确认 OCNF-淀粉-表面活性剂的表面电荷和相互作用，以便更深入地了解表面活性剂诱导的凝胶网络。
