氮化硼对水性膨胀型防火涂料性能的影响

Influence of Boron Nitride on Performances of Waterborne Intumescent Fire Retardant Coatings

对六方氮化硼和立方氮化硼分别进行了剥离和羟基化改性,并采用X射线衍射、红外光谱分析、BET比表面积分析和热重分析对其结构进行了表征。将剥离前后的六方氮化硼,以及羟基化改性前后的立方氮化硼作为功能性填料应用于水性膨胀型防火涂中,研究了这4种氮化硼对水性膨胀型防火涂料性能的影响。结果表明,它们均能明显提高膨胀型防火涂料的阻燃性能,其中剥离后的六方氮化硼的阻燃效果最好。羟基化改性以及剥离均可提高氮化硼阻燃性能。剥离不仅可以提高六方氮化硼的阻燃性,还可以提高其涂料的耐水性,可能是因为剥离后的六方氮化硼纳米尺寸更小,更趋近于片状(层数减少),利于在涂料以及碳层中的均匀分散,但羟基化改性由于提高了立方氮化硼的表面亲水性,因而降低了其涂料的耐水性。

The hexagonal boron nitride(HBN)and cubic boron nitride(CBN)were stripped and hydroxylated respectively,and characterized by X-ray diffraction,Fourier transform infrared spectroscopy,Brunauer-Emmett-Teller specific surface area analysis and thermogravimetric analysis.The HBN before and after stripping(stripped hexagonal boron nitride,SHBN)and CBN before and after hydroxylation(hydroxylated cubic boron nitride,HCBN)were used as functional fillers in waterborne intumescent fire retardant coatings.The effects of these boron nitride on the properties of waterborne intumescent fire retardant coatings were studied.The results show that all of them can obviously improve the flame retardancy of intumescent fire retardant coatings,and the SHBN has the best flame retardancy.Hydroxylation and stripping can improve the flame retardancy of CBN and HBN respectively.Stripping can not only improve the flame retardancy of HBN,but also improve the water resistance of the coating.The nano size of the SHBN is smaller and tends to be lamella(the number of layers is reduced),which induces its uniform dispersion in the coating and carbon layer.Hydroxylation improves the surface hydrophilicity of CBN,while reduces the water resistance of coatings.