阻燃隔热海鞘纤维素纳米晶体基气凝胶的制备及性能研究

Preparation and Properties of Flame Retardant and Thermal Insulation Tunicate Cellulose Nanocrystal-based Aerogel

关键词:  海鞘纤维素纳米晶体  氧化石墨烯  海泡石  阻燃  隔热  气凝胶

Key Words:tunicate cellulose nanocrystals  graphene oxide  sepiolite  flame retardant  thermal insulation  aerogel

摘要:以海鞘纤维素纳米晶体（TCNC）、氧化石墨烯（GO）和海泡石（SEP）为原料，戊二醛为交联剂，水为溶剂，通过冷冻干燥技术制备阻燃隔热气凝胶TCNC/SEP/GO。结果表明，气凝胶TCNC/SEP/GO的最佳制备工艺条件为GO含量10%，-196 ℃下定向冷冻成形。随着冷冻成形温度的降低，在压缩应变为0.5时，与纯TCNC气凝胶相比，制备的气凝胶TCNC/SEP/GO（GO含量10%）压缩应力增加约50%，导热系数降低23%。在燃烧测试中，纯TCNC气凝胶在9 s内出现自熄现象，而气凝胶TCNC/SEP/GO（GO含量10%）在0.42 s内出现自熄现象。此外，将后者浸泡在乙醇中，在12 s时出现自熄现象，且熄灭后仍保持原有形态，未发生坍塌。

Abstract:Tunicate cellulose nanocrystals （TCNC）， graphene oxide （GO） and sepiolite （SEP） were used as raw materials， the glutaraldehyde was used as adhesion agent with water as solvent to prepare the flame retardant and thermal insulation aerogel TCNC/SEP/GO by direct freeze-drying technique. The results showed that the optimum conditions for the preparation of aerogel TCNC/SEP/GO were GO content of 10% via directed freeze-forming at -196 ℃. At a compressive strain of 0.5， compared to pure TCNC aerogel， the prepared aerogel TCNC/SEP/GO （GO content of 10%） had about 50% increase in compressive stress and 23% decrease in the thermal conductivity with the freeze-forming temperature decreased. In the vertical combustion test， the pure TCNC aerogel extinguished in 9 s， while the aerogel TCNC/SEP/GO （GO content of 10%） extinguished in 0.42 s. In addition， when the latter was immersed in ethanol， it appeared to be extinguished at 12 s， with original form after extinguishing.