Abstract

To sodium alginate and acrylamide (AM) as raw material, using ammonium persulfate (APS) as initiator, N,N-methylene bisacrylamide (MBA) as crosslinking agent, SA/PAM-based fibrous aerogels are prepared by extrusion and freeze drying techniques based on dual network structure design. The results show that the best preparation process is one step molding, acrylamide 50 wt%, 1.2 mm spinneret pore size, 9 mm/min spinning rate, 3 wt% CaCl₂ coagulation bath, 5 min coagulation time. The aerogels present a microscopic multi-layered pore structure with macroporous intervening mesopores and micropores, and rendered as macroscopic fibrous. The average pore size of macropores is 2093.70 nm, the specific surface area is 230.00 m²/g, the porosity is 72.10%. The average pore size of mesopores and micropores is 40.44 nm, the specific surface area is 18 m²/g and the thermal conductivity of fiber aerogels/epoxy composites is 0.1321 w/m·k.

摘要

以过硫酸钠（APS）为引发剂，N，N-亚甲基双丙烯酰胺（MBA）为交联剂，以藻酸钠和丙烯酰胺（AM）为原料，通过挤出和冷冻干燥技术制备了基于SA / PAM的纤维状气凝胶。在双重网络结构设计上。结果表明，最佳制备工艺为一步成型，丙烯酰胺50 wt％，喷丝孔孔径1.2 mm，纺丝速度9 mm / min，CaCl ₂凝固浴3 wt％，凝固时间5 min。气凝胶呈现微观的多层孔结构，其间具有大孔的介孔和微孔，并呈现为宏观纤维状。大孔的平均孔径为2093.70 nm，比表面积为230.00 m ²/ g，孔隙率为72.10％。中孔和微孔的平均孔径为40.44 nm，比表面积为18 m ² / g，纤维气凝胶/环氧树脂复合材料的热导率为0.1321 w / m·k。