聚氨酯类化合物包覆聚磷酸铵及其在TPU中的应用

Polyurethane Compound Coated Ammonium Phosphate and Its Application in TPU

为得到兼具良好阻燃性能和力学性能的阻燃热塑性聚氨酯(PUR)弹性体复合材料,采用原位包覆的方式制备了三种不同的PUR类化合物包覆的聚磷酸铵(APP),并将其分别添加到热塑性聚氨酯弹性体(TPU)中。研究了不同的PUR类化合物包覆后APP的亲疏水性以及对TPU/APP复合材料阻燃性能和力学性能的影响。研究结果表明,经过二苯基甲烷二异氰酸酯(MDI),PUR以及含硅PUR(SiPU)包覆后,获得的三种MDIAPP,PUAPP和SiPUAPP都从亲水性变为了疏水性,水接触角分别为128°,134°和138°,这有利于APP的储存和运输。TPU/APP复合材料的阻燃性能和力学性能测试结果表明,仅有PUAPP可以使TPU的阻燃性能和力学性能同时提高。TPU/5PUAPP的拉伸强度为27.2 MPa,较TPU/5APP提高了6.7%,而断裂伸长率为672.0%,较TPU/5APP提高了4.8%。TPU/5PUAPP的极限氧指数值从TPU/5APP的26.5%提高到了27.1%,并能通过UL 94垂直燃烧测试V-0级,没有滴落;此外,热释放速率峰值、总热释放量以及总生烟量分别较TPU/5APP降低了43.2%,22.8%和41.1%。

In order to prepare thermoplastic polyurethane(PU)elastomer composites with good flame retardancy and mechanical properties at the same time,three kinds of polyurethane coated ammonium phosphate were prepared by in-situ coating on the surface of ammonium phosphate(APP).Then,three kinds of ammonium phosphate with different shell structures were added to thermoplastic polyurethane elastomer(TPU),respectively.The hydrophilicity of APP coated with different polyurethane compounds was studied and the effect on flame retardancy and mechanical properties of TPU/APP composites was also studied.The research results indicated that the obtained three kinds of MDIAPP,PUAPP and SiPUAPP all change from hydrophilicity to hydrophobicity after coating with diphenylmethane diisocyanate(MDI),PUR and silicon-containing PUR(SiPU),and the water contact angles are 128°,134°and 138°,respectively,which is beneficial to the storage and transportation of APP.The test results of flame retardancy and mechanical properties indicate that only PUAPP can improve the flame retardancy and mechanical properties of TPU simultaneously.The tensile strength of TPU/5PUAPP is 27.2 MPa,which is 6.7%higher than TPU/5APP,while the elongation at break is 672.0%,which is 4.8%higher than TPU/5APP.The limit oxygen index value of TPU/5PUAPP has increased from 26.5%(TPU/5APP)to 27.1%,and it can pass UL 94 V-0 level without dripping.In addition,the peak heat release rate,total heat release,and total smoke production are reduced by 43.2%,22.8%,and 41.1%,compared to TPU/5APP.