【作者】 夏英；

【导师】 蹇锡高；

【作者基本信息】 大连理工大学 ， 材料学， 2008， 博士

【摘要】 本论文工作系辽宁省自然科技基金项目(项目编号20052159)及大连市青年科技基金项目(项目编号2002214)的部分研究内容。针对目前含卤阻燃ABS材料因燃烧释放有毒、腐蚀性气体而受到生态环境制约的现状,本文选用无卤、低毒的膨胀型阻燃剂(IFR)作为ABS树脂的无卤阻燃剂,系统研究了IFR对ABS的阻燃作用及阻燃机理,分析探讨了IFR分别与硼酸锌(ZB)、分子筛(Zeolites)、蒙脱土复配阻燃ABS时的协同作用及影响因素,并对比分析了不同接枝增韧方法对阻燃ABS复合材料结构与性能的影响。主要研究工作如下:系统研究了由聚磷酸铵(APP)兼作酸源和气源,季戊四醇(PER)、聚酰胺6(PA-6)、聚碳酸酯(PC)分别为炭源所构成的三种IFR在不同配比及用量时对ABS复合材料阻燃性能、力学性能、加工性能及其炭化行为和微观结构的影响。结果表明,由APP、PER构成的IFR阻燃剂对ABS复合材料具有良好的膨胀阻燃效果,当两者配比为3∶1、加入量为30%时,ABS/APP/PER复合材料的阻燃性能、冲击与拉伸性能以及加工性能均高于ABS/APP/PA-6和ABS/APP/PC两种复合材料。但三种IFR对ABS复合材料的力学、加工性能均产生了不利影响,其中,尤以冲击强度的下降为重。探讨了硼酸锌(ZB)及4A、13X两种分子筛对ABS/APP/PER无卤阻燃复合材料的阻燃增效机理。结果表明,在ABS/APP/PER无卤阻燃材料中加入2%的ZB虽然能够进一步提高复合材料的阻燃性能,改善复合材料的弯曲强度、弯曲模量和加工性能,但对复合材料的冲击、拉伸性能产生了不利影响。与ZB、13X型分子筛相比,硅铝比较低、表面极性较强的4A分子筛具有最佳的阻燃增效作用,当加入1%的4A分子筛时,ABS/APP/PER无卤阻燃材料的阻燃性能、力学性能以及加工性能得到了全面提高和改善。选择十六烷基三甲基溴化铵(C16)、十八烷基三甲基氯化铵(C18)及双十八烷基氯化铵(2C18)三种插层剂对蒙脱土进行了有机化改性,研究了插层剂种类及用量对有机蒙脱土(OMMT)插层效果的影响。并以丙烯酰胺(AM)为单体,利用溶液接枝法制备了载体功能化的蒙脱土母料(FMMT)。分别采用一步法和功能母料法制备了ABS/OMMT/IFR和ABS/FMMT/IFR无卤阻燃复合材料,考察了两种蒙脱土与IFR的协同作用。结果表明,IFR与OMMT、FMMT均存在较好的阻燃协同作用,且以FMMT与IFR间的协同作用更为突出。在IFR添加量为20phr时,母料法ABS/FMMT/IFR(96/4/20)复合材料的阻燃、力学性能优于一步法ABS/OMMT/IFR无卤阻燃复合材料。与商品化的含卤阻燃ABS(PA-766、PA-769)相比,ABS/FMMT/IFR(96/4/20)复合材料的拉伸性能、弯曲性能及加工性能优于PA-766、PA-769,冲击性能与PA-766、PA-769相当。为了进一步提高无卤阻燃ABS复合材料的冲击韧性,以丙烯酸(AA)为单体,采用熔融接枝制备了ABS-g-AA增容剂。分别以直接添加增容法和原位反应增容法制备了添加增容的无卤阻燃ABS复合材料(T-ABS)和原位增容的无卤阻燃复合材料(Y-ABS)。分析比较了添加和原位反应两种增韧方法对ABS/OMMT/IFR复合材料结构与性能的影响。结果表明:采用添加法增韧ABS/OMMT/IFR复合材料时,ABS-g-AA增容剂对ABS/OMMT/IFR复合材料虽具有增韧作用,但亦引起了复合材料阻燃性能和加工性能的下降,且随其用量的增加,复合材料的阻燃性能和加工性能不断下降。与添加法增韧不同,原位生成的增容剂在赋予Y-ABS复合材料更为优良的力学性能的同时,可使复合材料保持原有的阻燃性能和加工性能,且成本较低,加工工序简单,从而使Y-ABS无卤阻燃复合材料的综合性能好于T-ABS无卤阻燃复合材料和商品化的PA-766、PA-769含卤阻燃ABS。更多还原

【Abstract】 This work was financially supported by the natural science foundation of Liaoning province (No.20052159) and the youth science and technology foundation of Dalian, China (No.2002114). At present, flame retardant acrylonitrile-butadiene-styrene (ABS) materials containing halogen are restricted in ecological environment because they produce lots of toxic gases and corrosive smokes while burning. In view of existing situation, intumescent flame retardant (IFR) with halogen-free and low toxicity was selected to be the main flame retardant for ABS. The flame retardant effect and mechanism of IFR on ABS was systematically studied. The synergistic effects between IFR and zinc borate (ZB), zeolite, montmorillonite respectively on ABS were investigated. And the influences of different toughening methods on structure and properties of flame retardant ABS composites were comparatively analysed. The main research contents are as the follows.Three kinds of IFR systems were established, of which, ammonium polyphosphate (APP) as an acid source and blowing agent, pentaerythritol (PER), polyamide-6 (PA-6), polycarbonate (PC) as a carbonization agent, respectively. The influences of ratio and amount of these IFR syetems on flame resistance, mechanical properties, processability, behavior of carbonization and microstructure of ABS composites were systematically researched. The results showed that IFR based on APP and PER had a good flame retardant effect on ABS composites. When the ratio of APP and PER was 3:1and the conten was 30%, the flame resistance, impact and tensile strength, and processability of ABS/APP/PER composites were higher than those of ABS/APP/PA-6 composites and ABS/APP/PC composites. However, three kinds of IFR brought bad effects on mechanical properties and processability, of which, the decrease of impact strength was more serious.The synergistic mechanisms of IFR with ZB, zeolite 4A and 13X were investigated. The results demonstrated that adding ZB with 2% content to ABS/APP/PER composites enhanced the flame resistance and modified the flexural strength, flexural modulus and processability. However, ZB produced bad influences on impact and tensile property. Compared with ZB and zeolite 13X, zeolite 4A with lower ratio Si/Al, stronger surface polarity had the best synergistic effect with IFR. When the content of zeolite 4A was 1 wt.%, the flame resistance, mechanical properties and processability of ABS/APP/PER composites were increased and modified on the whole. Montmorillonite was organized by three kinds of intercalating agents such as cetyhrimetheylammonium bromide (C16), octadecyltrimethyl ammonium chloride (C18) and bi-octadecyldimethyl ammonium chloride (2C18), and the effect of amount of different intercalating agents on intercalation of organic montmorillonite (OMMT) was studied. Selecting acrylamide (AM) as a monomer, the functionalized masterbatch of montmorillonite (FMMT) was prepared by grafting in solution. ABS/OMMT/IFR and ABS/FMMT/IFR composites were prepared by adopting one-step method and functionalized masterbatch method, respectively. The synergistic effects of two kinds of montmorillonite with IFR were investigated. The results showed that IFR had a synergistic effect with OMMT and FMMT, of which, synergistic effect between IFR and FMMT was more protruding. When the amount of IFR was 20phr, the flame resistance, mechanical properties of ABS/FMMT/IFR (96/4/20) composites were better than those of ABS/OMMT/IFR composites. Compared with commercial flame retardant ABS containing halogen (PA-766 and PA-769), the tensile and flexural properties of ABS/FMMT/IFR (96/4/20) composites were superior to that of PA-766 and PA-769, and its impact property was equivalent to that of PA-766 and PA-769.In order to make further increase in the toughness of non-halogen flame retardant ABS composites, ABS-g-AA graft was synthesized by melt grafting when acrylic acid (AA) as a monomer. Taking ABS-g-AA graft as a compatibilizer, non-halogen flame retardant ABS composites (T-ABS) toughened by the method of direct adding and non-halogen flame retardant ABS composites (Y-ABS) toughened by the method of in-situ reaction were prepared. The influences of two toughening methods of direct adding and in-situ reaction on structure and properties of ABS/OMMT/IFR composites were analysed comparatively. The results showed that adopting the method of direct adding, althougth ABS-g-AA had a toughening effect on ABS/OMMT/IFR composites, resulted in decreasing in flame resistance and processability of ABS/OMMT/IFR composites. And with the increasing of ABS-g-AA amount, flame resistance and processability of ABS/OMMT/IFR composites continually decreased. Unlike the method of direct adding, compatibilizer synthesized by the method of in-situ reaction could impart excellent mechanical properties to Y-ABS composites, meanwhile it made ABS/OMMT/IFR composites maintain its flame resistance and processability, and made Y-ABS composites have lower production cost and simple machining process. As a result, the comphrehensive properties of non-halogen flame retardant Y-ABS composites were better than those of T-ABS composites, PA-766 and PA-769.更多还原