Fiber and Polymer Technology, KTH Royal Institute of Technology, Teknikringen 56, SE-100 44 Stockholm, Sweden.
Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, Alessandria Site, Viale Teresa Michel 5, 15121, Alessandria, Italy.
Carbohydr Polym. 2020 Feb 15;230:115616. doi: 10.1016/j.carbpol.2019.115616. Epub 2019 Nov 14.
Wood-based cellulose fibers were used to prepare porous, low density and wet-stable fiber networks (FN). Multilayer coatings consisting of chitosan (CH), sodium hexametaphosphate (SHMP) and inorganic nanoparticles comprising of either sodium montmorillonite (MMT), sepiolite (SEP) or colloidal silica (SNP) were deposited by the layer-by-layer (LbL) technique onto FNs in an effort to impart flame-retardancy. A simulated fire scenario measured by cone calorimetry showed that five quadlayers (QL) of CH/SHMP/CH/MMT, CH/SHMP/CH/SEP and CH/SHMP/CH/SNP can produce significant reduction in peak heat release rate (pkHRR). In detail, the coating containing SEP showed the largest reduction of the pkHRR by 47% relative to the uncoated FN. MMT and SEP coated FNs were also able to self-extinguish fire and to retain their shapes after direct exposure to a methane flame. This study hence shows that the LbL assembly is a highly effective way to impart flame-retardant properties to this new type of porous FN.
木质纤维素纤维被用于制备具有多孔、低密度和湿稳定纤维网络（FN）的材料。壳聚糖（CH）、六偏磷酸钠（SHMP）和无机纳米粒子（包括钠蒙脱石（MMT）、海泡石（SEP）或胶体二氧化硅（SNP））的多层涂层通过层层（LbL）技术被沉积到 FN 上，以赋予其阻燃性。通过锥形量热法测量的模拟火灾情况表明，CH/SHMP/CH/MMT、CH/SHMP/CH/SEP 和 CH/SHMP/CH/SNP 的五层（QL）可以显著降低峰值热释放率（pkHRR）。具体而言，含有 SEP 的涂层相对于未涂层的 FN，pkHRR 降低了 47%。MMT 和 SEP 涂层的 FN 也能够自熄，并在直接暴露于甲烷火焰后保持其形状。因此，这项研究表明，LbL 组装是赋予这种新型多孔 FN 阻燃性能的一种非常有效的方法。
