氮化硼改性聚氨酯和聚丙烯酸系水基阻燃电缆涂层材料的性能研究

Properties of Polyurethane and Polyacrylic Water-based FlameRetardant Cable Coating Modified by Boron Nitride

以硼酸和三聚氰胺为主要原料,分别用不同方法制备了片状、纤维状和无规颗粒状的六方氮化硼(BN)。以片状BN为改性剂,氢氧化铝和三聚氰胺磷酸盐为阻燃剂,季戊四醇为成炭剂,加入其他分散剂和增黏剂分别制备了聚氨酯和丙烯酸系聚合物水基阻燃电缆涂料,对比研究了片状氮化硼对阻燃涂料改性前后的阻燃性能和力学性能的影响。研究结果表明,氮化硼改性能提高涂层的阻燃性能,改性后能降低涂层的热释放速率、总生烟量、质量热损失速率。氮化硼改性涂料与未改性前相比难以点燃,改性后的水性聚氨酯阻燃涂料和丙烯酸系聚合物的引燃时间分别达到65 s和78 s,比未添加氮化硼改性剂时分别提高25%和13%。添加氮化硼改性剂还能够提高涂料的力学性能,在阻燃剂添加量为30%、氮化硼改性剂的添加量为15%时,丙烯酸系聚合物涂料的拉伸强度可以达到9.72 MPa,而氮化硼改性后的聚氨酯涂料的拉伸强度则达到11.77 MPa。

Taking boric acid and melamine as main raw materials,hexagonal boron nitride(BN)with flake,fibrous and random particles were prepared by different methods.Flaky BN was more suitable for the modification of water-based flame retardant coatings.Polyurethane and acrylic polymer water-based flame retardant cable coatings were prepared by using aluminum hydroxide and melamine phosphate as flame retardants,pentaerythritol as carbon forming agents,and other components as dispersants and viscosifiers.The effect of synthesized flaky BN on the flame retardant and mechanical properties of flame retardant coatings before and after modification was studied comparatively.The results show that boron nitride could improve the flame retardant performance of the coatings,and reduce the heat release rate,the total amount of smoke and weight loss rate of them.The coating modified by BN is more difficult to ignite than that without modification.The ignition time of modified waterborne polyurethane flame retardant coatings and acrylic polymers could reach 65 and 78 s,respectively,which are 25%and 13%higher than those without boron nitride modifier.The addition of boron nitride modifier could also improve the mechanical properties of the coating.The tensile strength of acrylic polymer coating is 9.72 MPa,while that of polyurethane coating modified by boron nitride is 11.77 MPa,when adding 30%flame retardant and 15%boron nitride modifier.