BN@APP/水性聚氨酯复合材料的制备及其阻燃性能

采用聚磷酸铵(APP)对氮化硼进行表面改性,并进一步制备出聚磷酸铵改性氮化硼(BN@APP)/水性聚氨酯(WPU)复合材料.结果 表明,当BN@APP的添加量为0.75％时,BN@APP/WPU复合材料的拉伸强度是未改性WPU拉伸强度的2.2倍,这是因为BN@APP具有较大的比表面积以及与基体产生较强的相互作用.随着B...

Preparation and Flame Retardancy of Ammonium Polyphosphate Modified Boron Nitride/Waterborne Polyurethane Composites

Ammonium polyphosphate(APP)was used to modify the surface of boron nitride,and ammonium polyphosphate modified boron nitride(BN@APP)was further used to prepare BN@APP/waterborne polyurethane(WPU)composites.When the addition amount of BN@APP is 0.75%,the tensile strength of BN@APP/WPU composite is 2.2 times than that of unmodified WPU,owing to a large specific surface area of BN@APP and its strong interaction with the matrix.With the increase of addition amount of BN@APP,the peak heat release rate and the fire growth index of BN@APP/WPU composites gradually decrease,indicating the enhanced fire safety performance of WPU composites.Specifically,the peak heat release rate and total heat release of WPU composite containing 1%BN@APP are decreased by 24.5%and 6.9%,respectively,comparing with the unmodified WPU,implying the high flame retardant efficiency of BN@APP.The improved flame retardancy of WPU composites is attributed to their higher charring performance promoted by BN@APP.The increasing char yield could form an effective barrier layer on the surface of polyurethane during combustion,inhibit the thermal degradation of materials and the escape of combustible pyrolysis products,so as to improve the flame retardant performance.