Sornkamnerd Saranyoo, Okajima Maiko K, Kaneko Tatsuo
Energy and Environment Area, School of Materials Science, Graduate School of Advanced Science and Technology, Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan.
ACS Omega. 2017 Aug 31;2(8):5304-5314. doi: 10.1021/acsomega.7b00602.
Porous hydrogels possessing mechanical toughness were prepared from sacran, a supergiant liquid crystalline (LC) polysaccharide produced from . First, layered hydrogels were prepared by thermal cross-linking of film cast over a sacran LC solution. Then, anisotropic pores were constructed using a freeze-drying technique on the water-swollen layered hydrogels. Scanning electron microscopic observation revealed that pores were observable only on the side faces of sponge materials parallel to the layered structure but never on the top or bottom faces. The pore size, porosity, and swelling behavior were controlled by the thermal-cross-linking temperature. To clarify the freezing effect, a freeze-thawing method was used for comparison. The freeze-thawed hydrogels also formed layers but no pores. The mechanical properties and network structures of hydrogels were also studied, clarifying that porous hydrogels, even those with a high quantity of pores, were tough owing to the pores orienting along the layer direction like tunnels.
具有机械韧性的多孔水凝胶由聚谷氨酸制备而成，聚谷氨酸是一种由[具体来源]产生的超巨型液晶（LC）多糖。首先，通过热交联浇铸在聚谷氨酸LC溶液上的薄膜制备层状水凝胶。然后，在水溶胀的层状水凝胶上使用冷冻干燥技术构建各向异性孔。扫描电子显微镜观察表明，孔仅在平行于层状结构的海绵材料侧面可见，而在顶面或底面均不可见。孔径、孔隙率和溶胀行为由热交联温度控制。为了阐明冷冻效果，采用冻融法进行比较。冻融水凝胶也形成了层状结构，但没有孔。还研究了水凝胶的力学性能和网络结构，阐明了多孔水凝胶，即使是那些具有大量孔的水凝胶，由于孔沿层方向像隧道一样排列而具有韧性。
