胶合板表面层层自组装聚磷酸铵-壳聚糖/氮化硼及其阻燃性能

以杨木胶合板为研究对象，以聚磷酸铵-壳聚糖/氮化硼(APP-CS/BN)为阻燃涂层，通过层层自组装的方法将涂层整理到杨木胶合板上，以赋予胶合板一定的阻燃性能。FTIR和SEM结果显示，APP-CS/BN涂层在胶合板表面组装形成膜结构，组装膜均匀分布在材料表面。锥型量热仪(CONE)燃烧测试表明，与未经处理的胶合板相比，APP-CS/BN自组装涂层能有效延长胶合板点燃时间(TTI)，降低胶合板的热释放速率(HRR)和总热释放量(THR)，同时增加材料燃烧后成炭量。随着自组装涂层层数的增加，15层处理材、20层处理材、25层处理材的点燃时间较未处理材分别提升了100%、105%和125%；热释放速率峰值(Pk-HRR)较未处理材分别降低10.15%、22.34%和31.82%；阻燃处理杨木胶合板的THR，较未处理材分别降低2.89%、13.68%和15.32%；未处理材、15层处理材、20层处理材、25层处理材燃烧后成炭率依次为18.55%、24.07%、26.04%和27.65%。随着自组装层数的增加，杨木胶合板的阻燃性能随之增加，但当自组装层数由20层至25层时，胶合板阻燃能力提升的幅度变缓慢。本研究中，阻燃胶合板适宜自组装涂层数为20-25层。 

Flame retardancy of ammonium polyphosphate-chitosan/boron nitride on plywood surface via layer-by-layer self-assembly method

In order to endow poplar plywood with certain flame retardant properties, ammonium polyphosphate-chitosan/boron nitride (APP-CS/BN) were choosed as the flame retardant coatings, and were deposited on the plywood through layer by layer self-assembly method. The results of FTIR and SEM show that APP-CS/BN coatings are assembled on the surface of plywood to form a membrane structure, and the assembled membranes are evenly distributed on the surface of the material. Cone calorimeter (CONE) combustion tests show that APP-CS/BN self-assembled coatings effectively prolong the ignition time (TTI), reduce the heat release rate (HRR) and total heat release (THR) of the plywood, while increase the char residue which formed after combustion of the material. Compared to untreated plywoods, the ignition time of self-assembled plywoods with 15, 20, 25 APP-CS/BN layers increase by 100%, 105% and 125%, respectively; Pk-HRR is decreased by 10.15%, 22.34% and 31.82%; THR is decreased by 2.89%, 13.68% and 15.32%. The char formation rates of untreated plywood, self-assembled plywoods with 15, 20, 25 APP-CS/BN layers are 18.55%, 24.07%, 26.04% and 27.65%, respectively. In summary, the poplar plywood exhibits good flame retardant properties via layer-by-layer self-assembly flame retardant treatment. However, when the number of self-assembly layers is from 20 to 25, the increment amplitude of flame retardancy of plywood becomes slower. In this study, the suitable self-assembly coatings are 20-25 layers.