PA6/PP/SEBS-g-MAH共混物的相容性研究

采用马来酸酐接枝(氢化苯乙烯/丁二烯/苯乙烯)共聚物(SEBS-g-MAH)作为增容剂,研究了增容剂用量对尼龙6/聚丙烯(PA6/PP)共混体系相态结构、力学性能的影响,以及在相同增容剂用量下不同PA6、PP配比对体系相形态的影响。结果表明,SEBS-g-MAH中的酸酐基团能与PA6末端的氨基发生化学反应,在PA6和PP的内表面形成PA6-SEBS接枝共聚物,明显改善了两相的界面相容性,并使共混物的力学性能得到显著提高。共混物冲击断面形貌的分析表明,共混物发生了明显的脆韧转变。     

ABS树脂的无卤膨胀阻燃研究

以聚酰胺6(PA6)为协效成炭剂,将膨胀型阻燃剂聚磷酸铵(APP)应用于ABS树脂,通过氧指数(OI)测定及UL94测定,探讨了PA6、APP含量对阻燃体系阻燃性能的影响;同时,对复合体系进行了热失重分析,并采用扫描电镜(SEM)观察了复合物燃烧后炭层结构。结果表明:PA6的加入明显提升了体系成炭率,降低了最大热失重速率,ABS/PA6/APP体系燃烧表面形成了膨胀、均匀、致密的炭层结构。当PA6/ABS=20/80时,阻燃性能最佳,当APP含量为25%时,OI可以达到30%,UL94测定达V—1级;当APP含量为35%时,UL94测定达V—0级。     

PA66/SEBS复合材料的制备与性能研究

以聚酰胺66(PA66)和苯乙烯-乙烯-丁二烯-苯乙烯嵌段共聚物(SEBS)为原料,3份马来酸酐接枝苯乙烯-乙烯-丁二烯-苯乙烯共聚物(SEBS-g-MAH)为增容剂,通过熔融共混法制备了PA66/SEBS复合材料,研究了SEBS添加量对复合材料结晶性能、热性能、界面相容性、力学性能等的影响。结果表明:SEBS的加入没有改变PA66的特有晶型,仅仅改变了不同晶型的相对含量;随着SEBS用量的增加,PA66/SEBS复合材料的熔融温度、界面相容性下降,拉伸强度也呈逐渐降低的趋势;随着SEBS用量的增加,未加增容剂的复合材料的断裂伸长率呈逐渐减小的趋势,而加入增容剂的复合材料的断裂伸长率则呈先增后减的趋势;另外,加入了增容剂的复合材料的力学性能明显优于未加增容剂的复合材料。     

PPS/SEBS-g-MAH/PA46合金的制备及性能研究

通过合金化增韧改性PPS。在聚苯硫醚(PPS)中加入聚酰胺(PA46)和增容剂苯乙烯-乙烯-丁二烯-苯乙烯接枝马来酸酐(SEBS-g-MAH),通过熔融共混制备了PPS/SEBS-g-MAH/PA46合金;进一步使用二苯基甲烷二异氰酸酯(MDI)对PPS树脂进行活化处理,之后同样制备了活化PPS/SEBS-g-MAH/PA46合金。测试了合金的力学性能和热性能,并用扫描电镜观察了合金的微观结构形态。结果表明,加入增容剂后,合金的冲击强度有所提高;PPS树脂经过MDI活化后,合金的性能显著提高;当活化PPS/PA46质量比为70/30、SEBS-g-MAH质量分数为9%时,能制备出综合性能优良的合金材料,其冲击强度为8.4 kJ/m2,拉伸强度为61.2 MPa,弯曲强度为81.5 MPa,热变形温度为117℃。     

无机填料对PA6/MCA阻燃复合材料性能的影响

研究了不同种类的无机填料(硅灰石、碳酸钙)对尼龙6(PA6)/三聚氰胺氰尿酸盐(MCA)阻燃复合材料性能的影响。阻燃性能测试结果表明,PA6/MCA/硅灰石阻燃复合材料为UL94 V–0级,比PA6/MCA阻燃复合材料(V–2级)有显著提高;然而PA6/MCA/碳酸钙阻燃复合材料的极限氧指数却有所下降。扫描电子显微镜测试分析表明,PA6/MCA/硅灰石阻燃复合材料燃烧后的表面炭层呈连续、致密状;PA6/MCA/碳酸钙阻燃复合材料的表面炭层有很多孔洞,且孔洞直径大。傅立叶变换红外光谱测试结果表明,PA6/MCA/硅灰石阻燃复合材料的表面炭层与Si O2能很好地结合,形成致密的保护层,致使其阻燃性能显著提高。另外,力学性能测试结果表明,硅灰石能够提高PA6/MCA阻燃复合材料的拉伸强度,但降低了缺口冲击强度,而碳酸钙的加入却使得PA6/MCA阻燃复合材料的综合力学性能有所下降。     

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。     

组分对PA6/PP/滑石粉三元复合材料的影响

通过双螺杆挤出制备了尼龙6(PA6)/聚丙烯(PP)/滑石粉三元复合材料,考察不同PA6、PP及滑石粉和增容剂种类及含量对PA6/PP/滑石粉三元复合材料力学性能的影响。结果表明,中黏度(2.4~2.7 Pa·s)PA6、聚乙烯(PE)含量达到7%~9%的嵌段共聚PP及粒径为2~5μm的滑石粉制备的PA/PP/滑石粉三元复合材料具有优异的力学性能;随着PA6含量增加,PA6/PP/滑石粉三元复合材料的拉伸、弯曲强度增加,吸水率上升,PP含量增加,PA6/PP/滑石粉三元复合材料吸水率下降,拉伸强度和弯曲强度也下降;滑石粉的粒径越大,PA6/PP/滑石粉三元复合材料的刚性越好,冲击强度越差,滑石粉的粒径越小,则容易团聚,三元复合材料形成应力集中点;增容剂马来酸酐接枝乙烯-醋酸乙烯酯共聚物(EVAC-g-MAH)和马来酸酐接枝三元乙丙橡胶(EPDM-g-MAH)复配对PA6/PP/滑石粉三元复合材料增容效果优于马来酸酐接枝聚丙烯(PP-g-MAH)或EPDM-g-MAH;当EVAC-gMAH和EPDM-g-MAH添加量各为5%,PA6/PP/滑石粉质量比为50/20/20时,制备出的PA6/PP/滑石粉三元复合材料具有较佳的力学性能,并有优异的加工性能,其缺口冲击强度可达6.6 k J/m^2。     

无卤阻燃PPE/PA66合金的制备及性能

以多聚芳基磷酸酯和硼酸锌作为阻燃剂制备无卤阻燃聚苯醚(PPE)/尼龙66 (PA66)合金材料。分别讨论了PPE/PA66配比、阻燃剂多聚芳基磷酸酯用量及增容剂马来酸酐接枝聚苯醚(PPE-g-MAH)和增韧剂马来酸酐接枝苯乙烯–乙烯/丁烯–苯乙烯嵌段共聚物(SEBS-g-MAH)用量对PPE/PA66合金体系力学、耐热性能和阻燃性能的影响,并通过扫描电子显微镜观察了增容剂对合金表面形貌的影响。结果表明,PPE/PA66最佳配比为1/1 (质量比),阻燃剂的加入会影响合金材料的力学性能和耐热性,添加多聚芳基磷酸酯和硼酸锌的最优质量分数分别为15%和2%;PPE-g-MAH的加入有效改善了PPE与PA66之间的相容性,但添加量不宜过大,以质量分数6%为宜;SEBS-g-MAH可以有效改善合金的韧性,但会降低合金的阻燃性能,以质量分数5%为宜;最终制备的阻燃PPE/PA66合金材料的阻燃性能可达到V–0级(1.6mm),热变形温度达95.2℃,拉伸强度为61.9MPa,缺口冲击强度为108.4J/m。     

PA6/SEBS-g-MAH/OMMT/GMA共混物的制备和性能研究

以马来酸酐(MAH)接枝苯乙烯-(乙烯-丁烯)-苯乙烯共聚物SEBS(SEBS-g-MAH)为增韧剂,有机蒙脱土(OMMT)为增强填料,甲基丙烯酸缩水甘油酯(GMA)为相容剂,采用熔融挤出方法制备了PA6/SEBS-gMAH/OMMT复合材料.通过力学、毛细管流变性能测试,考察了SEBS-g-MAH、OMMT和GMA对共混物的力学性能及流变性能的影响.结果表明,共混材料能在保持基本强度及模量稳定的情况下提高冲击强度,获得良好的综合力学性能.PA6及其共混物均为假塑性流体,在230～260℃共混材料的非牛顿指数为0.603～0.931,表观黏度随着剪切应力的增加而降低;加入SEBS-g-MAH、OMMT和/或GMA使得PA6的表观黏度增大,黏流活化能降低;在恒定剪切应力下PA6共混物可在较宽的温度范围内成型加工.     

共单体固相接枝PP对PA6/PP合金增容作用的研究

研究了马来酸酐、苯乙烯共单体固相接枝聚丙烯[PP-g-(MAH-co-St)]增容尼龙6(PA6)/PP合金的两相形态结构、力学性能及结晶性能.结果表明,PP-g-(MAH-co-St)是PA6/PP合金的有效增容剂,少量的PP-g-(MAH-co-St)即可达到良好的增容效果,能够显著提高合金的力学性能.加入增容剂后,PP在基体PA6中的分散更均匀,颗粒尺寸更细小.增容剂使PA6/PP合金的结晶性能发生改变,PP结晶度增加,PA6结晶度下降.     

氧化锌催化膨胀型阻燃剂对PP阻燃及力学性能的影响

研究了氧化锌催化膨胀型阻燃剂(APP/PER)对PP阻燃和力学性能的影响。研究表明,当APP/PER质量比为20/10,ZnO的质量分数为1．3%时,阻燃PP的LOI值达到最大；同时阻燃PP的拉伸强度和冲击强度比不含ZnO的PP有所提高。TG结果表明,ZnO的加入使阻燃PP燃烧时降解过程加快并生成更多的剩炭,形成稳定的保护层,从而提高了PP的阻燃效果。SEN的形貌观察表明,加入ZnO的试样燃烧炭膜孔径较小、孔膜较厚。     

Functionalized elastomeric compatibilizer in PA 6/PP blends and binary interactions between compatibilizer and polymer

Superior impact properties were obtained when maleic anhydride grafted styrene ethylene/butylene styrene block copolymer (SEBS-g-MAH) was used as a compatibilizer in blends of polyamide 6 (PA 6) and isotactic polypropylene (PP), where polyamide was the majority phase and polypropylene the minority phase. The optimum impact properties were achieved when the weight relation PA:PP was 80:20 and 10 wt% SEBS-g-MAH was added. The blend morphology was systematically investigated. Transmission electron microscopy (TEM) indicated that the compatibilizer forms a cellular structure in the PA phase in addition to acting as an interfacial agent between the two polymer phases. In this cellular-like morphology the compatibilizer appears to form the continuous phase, while polyamide and polypropylene form separate dispersions. In microscopy, PA appeared as a fine dispersion and PP as a coarse dispersion. The mechanical properties indicated that in fact PA, too, is continuous, and the blend can be interpreted as possessing a modified semi-interpenetrating network (IPN) structure with separate secondary dispersion of PP. The coarser PP dispersion plays an essential role in impact modification. Binary blends of the compatibilizer and one blend component were also investigated separately. The same cellular structure was observed in the binary PA/SEBS-g-MAH blends, and SEBS-g-MAH again appeared to form the continuous phase when the elastomer concentration was at least 10 to 20 wt%. By contrast, in PP/SEBS-g-MAH only conventional dispersion of elastomeric SEBS-g-MAH was observed up to 40 wt% elastomer. Impact strength was improved and the elastic modulus was lowered in both PA/SEBS-g-MAH and PP/SEBS-g-MAH blends when the elastomer content was increased. The changes in modulus indicate that the semi-IPN-like structure is formed in the binary PA/SEBS-g-MAH blends as well as in the ternary structure.     

Effect of Phosphorus-Based Flame Retardants and PA6 on the Flame Retardancy and Thermal Degradation of Polypropylene

The investigation mainly focuses on the effect of polyamide 6 (PA6) and phosphorus based flame retardants (FRs) on improving the flame retardancy of polypropylene (PP). The flame retardant properties have been studied by limiting oxygen index, vertical burning test tests and cone calorimeter testing. The results demonstrate that PA6 and FRs can greatly improve the flame-retardant and thermal properties of PP. It’s found that the addition of PA6/APP/FRs can promote the formation of stable intumescent char layers. Those indicate that the flame retardancy of PA6/APP/FRs/PP composites is improved by the condensed-phase action of PA6/APP/FRs.     

改性聚磷酸铵对三嗪类膨胀阻燃聚丙烯性能的影响

由改性聚磷酸铵(APP)、自制的三嗪类成炭发泡剂(CFA)等复配制成膨胀型阻燃剂(IFR),以二氧化硅、二氧化钛等为协效剂阻燃聚丙烯(PP)。研究了不同组分的IFR及协效剂对阻燃PP复合材料阻燃性能、力学性能和耐水性能的影响。结果表明:改性APP的亲水性下降;由改性APP/CFA(4/1)、二氧化硅协效剂复配的PP复合材料阻燃性能、力学性能优良,助剂在PP基体中分散性好,热水浸泡后氧指数为32.5%,仍能达到UL94V—1级,失重率为2.92%。     

新型磷-氮系复配阻燃剂在聚丙烯中的应用

采用一种新型磷-氮系阻燃剂与聚磷酸铵(APP)复配成膨胀型阻燃剂,对聚丙烯(PP)进行阻燃改性。研究了阻燃PP的阻燃性能、热分解过程及力学性能。结果表明:当复配阻燃剂添加量为30%时,阻燃改性PP的氧指数和垂直燃烧等级分别达到32.3%和UL94 V-0级,拉伸强度为37.4 MPa,缺口冲击强度为39.5 kJ/m2,并且具有很好的热稳定性。     

Effect of novel copolyamide charring agents on flame‐retarded polypropylene

In this article, two novel copolyamide charring agents, ES‐6 and M‐170, were served as charring agents or synergist with ammonium polyphosphate (APP) and dipentaerythritol (DPER) for the flame‐retarded polypropylene (PP). The flame‐retardant system was characterized by limiting oxygen index (LOI), tensile strength, Izod impact strength, thermogravimetric analyses, differential scanning calorimeter (DSC), and scanning electron microscope (SEM). Compared with polyamide 6 (PA6), ES‐6 and M‐170 had better dispersion and compatibility in the PP matrix and enhanced mechanical properties. Meanwhile, as low melting point polyamides, ES‐6 and M‐170 could decrease processing temperature and effectively inhibit side reaction, especially the degradation of APP. In addition, the synergistic effect between ES‐6 and DPER was also investigated. The results showed that the synergistic system containing ES‐6 had better flame retardancy and mechanical performance in comparison with the system only using DPER or the system containing PA6. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers     

Using PA6 as a charring agent in intumescent polypropylene formulations based on carboxylated polypropylene compatibilizer and nano‐montmorillonite synergistic agent

The intumescent fire retardant polypropylene (IFP/PP) filled with ammonium polyphosphate (APP), melamine (M), and PA6 (charring agent) is discussed. Intumescing degree (ID) and the char yield were determined. Only when the three main components of IFR coexist at appropriate proportions, it has optimal ID and higher char yield. The appropriate proportion is PA6 : APP : M = 10 : 10 : 5. A new compatibilizer, carboxylated polypropylene (EPP), was added to PP/PA‐6 blend. Flow tests indicated that the apparent viscosity increased with the addition of EPP, thermal characterization suggested that EPP has reacted with PA6, PA6‐g‐EPP cocrystallized with PA6, and EPP‐g‐PA6 cocrystallized with PP; SEM micrographs illustrated that the presence of EPP improved the compatibility of PP and PA6. All the investigations showed that EPP was an excellent compatibilizer, and it was a true coupling agent for PP/PA6 blends. Using PA6 as a charring agent resulted in the IFR/PP dripping, which deteriorated the flammability properties. The addition of nano‐montmorillonite (nano‐MMT) as a synergistic agent of IFR enabled to overcome the shortcoming. The tensile test testified that the addition of nano‐MMT enhanced the mechanical strength by 44.3%. SEM showed that nano‐MMT improved the compatibility of the composites. It was concluded that the intumescent system with nano‐MMT was an effective flame retardant in improving combustion properties of polypropylene. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 739–746, 2006     

无卤膨胀阻燃PP/PA6合金性能研究

研究了以聚磷酸铵（APP）、三聚氰胺（MA）和层状复合金属氢氧化物（LDH）复配得到的膨胀阻燃剂（IFR）对聚丙烯／尼龙6（PP／PA6）合金性能的影响，分析了不同阻燃体系对PP／PA6合金的阻燃性能、力学性能、热性能和微观形态的影响。结果表明，当APP／MA／LDH为21．0／7．5／1．5（质量比）时，PP／PA6合金具有较好的阻燃性能并能保持较高的力学性能。LDH可以提高阻燃材料的热稳定性和残炭量，而且SEM照片显示炭层微观形态为“面包”状的膨松状。     

水滑石对PBS/Sb2O3阻燃PA6/GF性能的影响

研究了聚溴化苯乙烯(PBS)对玻纤增强尼龙6(PA6/GF)阻燃和力学性能的影响,并采用锥形量热仪研究了改性水滑石(HT)对PBS/Sb2O3阻燃PA6/GF抑烟作用和燃烧时热释放速率的影响。结果表明,随PBS用量增加,PA6/GF的氧指数增加,阻燃性提高,当PBS质量分数为20%时,PA6/GF的垂直燃烧达到FV-0级;HT燃烧后形成多孔、大比表面积的镁铝复合氧化物,能够有效吸附材料燃烧过程中产生的炭微粒,对PBS/Sb2O3阻燃PA6/GF具有显著的抑烟作用。当HT质量分数为5%时,烟释放速率降低27.6%,且对阻燃PA6/GF的力学性能影响不大。另外,HT使PA6/GF的氧指数和相比漏电起痕指数(CTI)提高。