膨胀阻燃剂/纳米黏土复配阻燃ABS

通过熔融共混法制备了有机化纳米黏土(OMMT)与膨胀型阻燃剂(IFR)复配阻燃丙烯腈-丁二烯-苯乙烯共聚物(ABS),并以苯乙烯/乙烯-丁烯/苯乙烯共聚物接枝马来酸酐(SEBS-g-MAH)作为增容剂。采用冲击和拉伸试验方法对材料的力学性能进行表征,采用极限氧指数(LOI)、垂直燃烧(UL94)和锥形量热(Cone)试验对材料的燃烧行为进行分析。结果发现,加入增容剂SEBS-g-MAH后,膨胀型阻燃剂与ABS的相容性得到提高,力学性能得到大幅提高。例如,5%SEBS-g-MAH加入到ABS/IFR(60/40)复合材料中,冲击强度提高至9 kJ/m^2,与未添加SEBS-gMAH体系相比,冲击强度的提升幅度较大。SEBS-g-MAH对复合材料体系的传统阻燃性能的影响较小。适量纳米黏土与膨胀型阻燃剂的复配可以进一步降低ABS树脂力学性能的损失,对传统阻燃性能(LOI和UL 94垂直燃烧级别)的影响较小,在ABS/IFR/SEBS(75/25/5)复合材料体系中,加入纳米黏土后,高温下可以形成阻隔炭层,隔绝热量和氧气。因此,与纯ABS和ABS/IFR/SEBS(75/25/5)复合材料体系相比,纳米黏土能显著降低ABS树脂在锥形量热测试中的热释放速率、热释放速率的峰值和总的放热量,有利于减缓火灾蔓延的速度。

ABS Flame Retarded by Compound of Intumescent Flame Retardant and Nanoclay

Acrylonitrile-butadiene-styrene copolymer ( ABS) flame retarded by intumescent flame retardant ( IFR) and organic nanoclay ( OMMT) was prepared through melt blending, and styrene-ethylene-butylene-styrene block copolymer grafted maleic anhydride ( SEBS-g-MAH) was introduced as a compatibilizer. The mechanical properties were characterized through the impact test and tensile test. The combustion behaviors were tested through the limit oxygen index ( LOI), vertical burning (UL94 ) and cone calorimeter test. The compatibility of IFR and ABS was improved with the addition of SEBS-g-MAH. And the mechanical properties could be improved with the addition of SEBS-g-MAH in PP/IFR composite. For example, when the addition of SEBS-g-MAH was 5%,the impact strength of the ABS/IFR ( 60/40) composite was increased to 9 kJ/m^2, which was much higher than those without SEBS-g-MAH. No change of combustion behaviors was found in the composite. The mechanical properties and few effects on the traditional flame retardant performance ( LOI and UL94 vertical burning level) were increased by appropriate compound of intumescent flame retardant and nanoclay. A barrier char layer was formed by the addition of nanoclay in the ABS/IFR/SEBS( 75/25/5 ) composite in high temperature. Heat and oxygen were isolated by the char layer. Therefore, the addition of nanoclay significantly reduced the peak hear release rate, heat release rate and total heat release in Cone tests, compared with pure ABS and ABS/IFR/SEBS ( 75/25/5 ) composite, which was helpful to slow the spread of fire.