核壳型碳微球和碳纳米管的制备及其阻燃性能

为改善碳微球(CMSs)/碳纳米管(MWNTs)与聚对苯二甲酸乙二醇酯(PET)基体相容性,采用原位聚合法对CMSs和MWNTs分别进行表面修饰,制成核壳型结构的PET@CMSs(PCMSs)和PET@MWNTs(PMWNTs),并通过熔融共混法制备了PCMSs/PMWNTs/PET复合材料,对其阻燃性能进行探讨。使用TEM、SEM、FTIR、TGA、CONE等测试手段,表征了PCMSs与PMWNTs的结构及与PET基体的相容性,并测试了PCMSs/PMWNTs/PET的力学性能、阻燃性能、热稳定性和燃烧行为等。结果表明,与修饰前的CMSs/MWNTs相比,PCMSs/PMWNTs与PET基体具有更好的分散相容性,在PCMSs\PMWNTs添加的质量分数为1%,PCMSs与PMWNTs的质量比为1∶2时,PCMSs/PMWNTs/PET比CMSs/MWNTs/PET的抗拉强度提高的最大,可达26.1%;与纯PET、CMSs/MWNTs/PET相比,PCMSs/PMWNTs作为阻燃材料添加到PET中,具有较好的热稳定性、且有效延长了PET的点燃时间、增大FPI指数,从而降低火灾危险性,阻燃效果较好,其LOI值为28.1%,熔滴数为3 d/min,UL-94阻燃级别可达到V-0级。

Preparation of Core-shell Structural Carbon Microspheres and Carbon Nanotubes and Their Flame Retardant Properties

To improve the compatibility between carbon microspheres (CMSs)/multi-walled carbon nanotubes (MWNTs) and polyethylene terephthalate (PET), core-shell structural PET@CMSs (PCMSs) and PET@MWNTs (PMWNTs)) were prepared by situ polymerization. The PCMSs/PMWNTs/PET composite materials were produced through the method of melt blending, and the flame retardant properties of PET composites were discussed. The structures of PCMSs and PMWNTs and the compatibilities of PCMSs/PMWNTs in PET matrix were measured by transmission electron microscopy (TEM), scanning electron microscope (SEM) and fourier transform infrared spectroscopy (FTIR). The mechanical properties, flame retardancy and thermal stability of PET composite materials were characterized by the universal electronic testing machine, limiting oxygen index (LOI), vertical burning method (UL-94), thermogravimetric (TG) and cone calorimeter (CONE). The results show that compared with CMSs/MWNTs, the modified PCMSs/PMWNTs has better compatibility. When the mass fraction of nanomaterial is 1%, and the mass ratio between PCMSs and PMWNTs is 1 to 2, PCMSs/PMWNTs/PET achieves the highest tensile strength, with a significant increase of 26.1% of the tensile strength of CMSs/MWNTs/PET. Moreover, PCMSs/PMWNTs/PET effectively prolongs the ignition time of PET and increases the FPI values to reduce the risk of fire. The flame retardancy of PCMSs/PMWNTs/PET is higher than that of CMSs/MWNTs/PET, with the LOI being 28.1%, the droplet 3 d/min and the UL-94 ratingV-0.