PA6/ABS的结构与力学性能研究

采用熔融共混法制备了苯乙烯-马来酸酐共聚物(SMA)增容的聚酰胺6/丙烯腈-丁二烯-苯乙烯共聚物(PA6/ABS)共混物,用扫描电镜(SEM)对PA6/ABS共混物结构进行了表征.结果表明,随着SMA含量的增加,PA6/ABS共混体系的橡胶相粒径减小.橡胶颗粒的多分散系数保持不变,基体层厚度逐渐减小;PA6/ABS共混体系的脆韧转变温度随SMA含量的增加先减小后增加.     

温度和测试速率对PA 6/ABS共混物韧性的影响

采用熔融共混方法制备苯乙烯-马来酸酐共聚物(SMA)增容的PA 6/ABS共混物,考察温度和测试速率对PA 6/ABS共混物韧性的影响.结果表明:共混物的缺口冲击强度随着温度升高而提高,达到脆-韧转变温度后冲击强度急剧增加,超过脆-韧转变温度后,共混物的冲击强度基本不变;随着夹头移动速率的增加,PA 6/ABS共混物的裂纹引发功先减少后增加,裂纹扩展功随夹头移动速率增加而先增加后减少.     

超韧PA6/ABS合金性能和断口形貌研究

以幕乙烯-马来酸酐共聚物(SMA)为增容剂,研究了SMA含量对PA6/ABS共混物力学性能和断口形貌的影响.实验结果表明:随着SMA含量的增加,PA6/ABS共混物的拉伸强度逐渐增加,冲击强度先增加,接着保持不变,后降低;PA6/ABS共混物冲击断面可分为裂纹稳定扩展区与快速扩展区,SMA质量含量超过临界值后稳定扩展区相对面积明显减少,且使稳定扩展区相对面积明显减少的SMA临界含量随着共混物中ABS含量增加而增加.     

SMA增容PA1012/ABS共混物的研究

采用熔融共混方法制备一系列尼龙1012(PA1012)/丙烯腈-丁二烯-苯乙烯共聚物(ABS)/苯乙烯-马来酸酐共聚物(SMA)共混物,利用冲击试验仪、示差扫描量热仪(DSC)和扫描电子显微镜(SEM)等手段,探究增容剂SMA和ABS的添加量对PA1012/ABS共混物性能的影响。结果表明,当SMA含量为5%且ABS含量为50%时,PA1012/ABS/SMA共混物的缺口冲击强度最优,为669 J/m;随着SMA含量增加,结晶温度有先增大后减小趋势,并且与纯PA1012相比,PA1012/ABS/SMA共混物结晶温度升高了10℃,促进PA1012结晶;SMA加入后,ABS分散相粒子尺寸减小,PA1012和ABS间界面黏结作用增强,证实SMA对PA1012/ABS有明显增容作用。     

超韧PA6/ABS合金的制备

以苯乙烯-马来酸酐（SMA）共聚物为增容剂，考察了ABS及SMA的含量对PA6／ABS共混体系的力学性能的影响；并利用SEM研究了PA6／ABS冲击断面的相结构。研究表明：SMA是PA6／ABS共混体系的有效增容剂。随着其含量的增加，分散相ABS粒子的尺寸减小，分散更加均匀，能显著地改善PA6／ABS共混物的冲击、拉伸和弯曲性能。在该共混体系中，ABS含量的增加能够大幅度地提高PA6／ABS共混物的冲击韧性；但当ABS含量超过10％时，将使PA6／ABS共混物的拉伸和弯曲性能明显下降。SMA的添加量为0．5％，且质量比为90／10的PA6／ABS共混体系能保持较好的加工性能，制备的PA6／ABS合金具有最佳的综合力学性能和超高韧性．Izod缺口冲击强度高达1200J／m。     

高性能PA6/ABS合金的研制

分别以接枝ABS、苯乙烯-马来酸酐接枝物（SMA）和苯基马来酰亚胺共聚物为相容剂,考察了它们对PA6/ABS共混体系相容性和力学性能的影响。并研究了PA6/ABS共混体系中PA6、ABS树脂的选择对共混物冲击韧性的影响。研究表明,接枝ABS、SMA和苯基马来酰亚胺共聚物都是PA6/ABS共混体系的有效增容剂,能显著改善PA6/ABS共混物的相容性并提高共混物的机械力学性能。选用高粘度的PA6树脂有利于提高共混体系的冲击韧性,提高高胶含量ABS用量有助于获得高低温冲击性能优异的PA6/ABS合金材料。     

共混方式对ABS／PA6／SMA共混体系形态和力学性能的影响

以苯乙烯-马来酸酐共聚物（SMA）为反应增容剂，研究不同共混工艺和ABS／PA6配比对三共混体系聚集态结构和力学性能的影响。结果表明：SMA对共混体系增容效果显著，并明显改善了ABS／PA6共混体系的力学性能。其中当PA6用量为30份和40份时，SMA先与ABS共混再与PA6共混的方式所生成共混物的性能优于SMA先与PA6共混再与ABS共混的方式。PA6用量为30份时性能最好，共混物的分散相尺寸达到最小值0．31μm，分散相颗粒PA6周长面积比为最大值0．46，拉伸强度和冲击强度也分别为最大值63．2MPa和8．29kJ／m^2。当PA6用量达到45份时，共混方式对共混物的力学性能影响不大。研究表明，当ABS为连续相时，共混方式可以强烈地影响ABS／PA6共混物体系的聚集态结构和力学性能，而PA6和ABS向共连续相发展时，共混方式对ABS／PA6聚集态结构和力学性能则影响不大。     

PA6/ABS共混物性能研究

将聚酰胺6（PA6）与市售的丙烯腈-丁二烯-苯乙烯（ABS）树脂共混,制备PA6/ABS共混物。研究了ABS树脂的用量对PA6/ABS共混物力学性能的影响;采用苯乙烯及丙烯腈共聚物（SAN）和ABS粉料熔融共混制得不同胶含量的ABS/SAN共混物。研究了不同胶含量的ABS/SAN共混物对PA6/ABS共混物力学性能的影响。在PA6/ABS/SAN共混物中引入苯乙烯-丙烯腈-马来酸酐共聚（SAM）树脂取代部分SAN树脂,研究了SAM树脂的加入及引入顺序的不同对共混物性能的影响。结果表明, ABS树脂的用量在50%～60%左右时共混物性能最佳。随ABS/SAN共混物胶含量提高,共混物的拉伸强度、弹性模量、弯曲强度和弯曲模量逐渐降低。随SAM树脂替代SAN量增加,共混物的拉伸和弯曲性能先降低后增加。但共混物熔体流动速率降低明显,而SAM树脂的引入顺序对共混物的力学性能影响不大。     

PA6/ABS/SMA/OMMT共混物的结构与性能研究

研究了有机蒙脱土(OMMT)对尼龙6(PA6)/丙烯腈-丁二烯-苯乙烯(ABS)/苯乙烯-马来酸酐共聚物(SMA)合金体系聚集态结构及性能的影响。实验表明:OMMT的加入提高了PA6/ABS合金体系的强度及模量,但加入OMMT后共混物的韧性有所下降。TEM的分析结果表明:对PA6/ABS/SMA/OMMT共混物,OMMT用量小于2份时,PA6/ABS/SMA/OMMT共混物中OMMT基本以剥离形态分布。     

SAN—g—GMA的制备及其在PA6／ABS中的应用

采用固相接枝制备苯乙烯/丙烯腈共聚物接枝甲基丙烯酸缩水甘油酯(SAN-g-GMA),研究了过氧化苯甲酰(BPO)和GMA用量对接枝吸光比的影响,以自制的SAN-g-GMA增容尼龙6/丙烯腈-丁二烯-苯乙烯(PA6/ABS)共混物,探讨了SAN-g-GMA对共混物结构与性能的影响.结果表明:SAN-g-GMA能够增容PA6/ABS共混物,改善共混物的力学性能;Molau实验发现,SAN-g-GMA能够促进PA6/ABS两相界面结合,起到相容作用;共混物的SEM照片表明,SAN-g-GMA使ABS在PA6中分散均匀,粒子尺寸减小.     

两类PE-HD/E-TMB共混物的脆韧转变及断面形态

用自制增韧母料(E-TMB)分别与2200J型高密度聚乙烯(PE-HD)(HE1)和2911型PE-HD(HE2)热机械共混制得HE1/E-TMB和HE2/E-TMB共混物,用力学性能测试法和扫描电子显微镜研究了两类共混物的脆韧转变和断面形态。结果表明,HE1/E-TMB共混物比HE2/E-TMB共混物在弹性体含量较低的情况下发生脆韧转变,二者的脆韧转变区分别是共混物弹性体质量分数的3%～10%和10%～14%;弹性体质量分数为8%时,HE1/E-TMB共混物的冲击断面为韧性断裂,HE2/E-TMB共混物的冲击断面为脆性断裂,二者属于不同的断裂机理。     

聚酰胺弹性体增韧聚乳酸改性研究

选用聚酰胺弹性体(聚酰胺和聚氧乙烯的共聚物,PAE)与聚乳酸(PLA)熔融共混进行增韧改性。结果表明,当PAE弹性体含量在20%～30%(质量分数,下同)之间时,共混体系发生脆韧转变,最大冲击强度达到67.6J/m,但拉伸强度和模量大幅度下降;PAE弹性体含量为5%～10%时共混体系的拉伸强度保持率最高,而且断裂伸长率提高近40倍,综合性能较好;虽然扫描电子显微镜照片显示共混体系为两相分离,但是差示扫描量热分析数据均表明,随着PAE弹性体含量的增加,共混体系的玻璃化转变温度和熔点发生相应变化,证明该共混体系为半溶混性,即两相间存在一定的相互作用;热失重分析数据显示,PAE弹性体在一定程度上提高了PLA的热降解温度。     

Reactive compatibilization of the polyamide 6/poly(phenylene oxide) blend by means of styrene–maleic anhydride copolymer

The compatibilization of the polymer blend polyamide 6/poly(phenylene oxide) (PA-6/PPO) system has been studied using the reactive random copolymer styrene–maleic anhydride (SMA) as a compatibilizer precursor. SMA is miscible with PPO when the MA content of SMA is not higher than 8 wt %. The anhydride groups of SMA react with the amino end groups of PA-6 during melt blending to form a graft copolymer at the interface with a compatibilizing effect as a result. Two different blending procedures were compared to each other and the compatibilizing effect of the added SMA was evaluated for a matrix/dispersed particle type of morphology. The effect of the different material parameters such as the functionality of SMA (wt % MA in SMA) and the molecular weight of PA-6, and blending parameters such as the extrusion time was analyzed with respect to the blend phase morphology. Finally, the amount of reacted MA groups in the blends PA-6/(PPO/SMA) was determined with FTIR after the use of an extraction method to remove the PA-6 matrix phase. The comparison between the morphological data (particle size reduction of the dispersed PPO/SMA phase) and the FTIR data (amount of reacted MA groups) of the blends considered, turned out to be very logical. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 889–898, 1999     

PP/EPDM/纳米弹性体粒子三元共混体系的脆韧转变

研究了PP／EPDM／纳米弹性体粒子(ENP)三元共混体系的脆韧转变行为。结果表明，与PP／EPDM二元共混物相比，三元共混物的脆韧转变可以在EPDM质量分数较低的情况下发生；在橡胶总质量分数相同的情况下，三元共混物有更高的冲击强度，拉伸强度有一定提高。从脆断样条的扫描电镜照片观察到，在相同EPDM质量分数下，PP／EPDM／ENP三元共混物中的EPDM粒子明显细化，分布均一，粒子间距减小，这是脆韧转变提前的原因。     

聚合物脆韧转变判据及影响因素研究进展

综述了聚合物脆韧转变的几种判据,其中着重介绍了Bucknall判据、临界基体层厚度判据、损伤竞争准数判据、分子链参数判据、临界黏结条件判据等。而且结合聚合物脆韧转变判据,分析了基体性质、分散相形态、界面黏结强度以及外界因素对聚合物脆韧性的影响,并指出了结合各因素的影响综合考虑聚合物脆韧转变判据的研究方向。     

淀粉基生物降解材料的制备及其力学性能的研究

以淀粉、PVA、水、甘油和硼砂为原料制备了淀粉基全降解材料,对其力学性能进行了研究。结果表明,以30份水做增塑剂,加入25份PVA时,材料的拉伸强度和断裂伸长率分别从纯淀粉的25.80MPa和1.11%提高到31.78MPa和6.24%,同时应力-应变曲线表明,材料从脆性断裂转变为无屈服点的韧性断裂,说明PVA增韧作用明显;硼砂可以使PVA和淀粉发生交联,制得材料的拉伸强度可达43.37MPa,但材料韧性较差;甘油的加入虽可以使材料的断裂伸长率提高,但拉伸强度明显降低;同时加入硼砂和甘油,材料的强度和韧性同时得到改善,拉伸强度和断裂伸长率分别提高到36.26MPa和11.71%。     

Properties of blends of starch and synthetic polymers containing anhydride groups. II. Effect of amylopectin to amylose ratio in starch

Corn starch with different amylopectin to amylose ratios was blended with styrene maleic anhydride copolymer (SMA) and ethylene–propylene-g-maleic anhydride copolymer (EPMA). The starch had an amylose content of approximately 0, 50, and 70%. The concentration of starch in the blend was kept constant at 60% by weight. The samples were melt blended in a corotating twin screw extruder. Scanning electron micrographs showed that the amount of starch granules remaining in the samples varied with the torque. Optical micrograph showed that starch/EPMA blends formed a cocontinuous phase in all blends irrespective of starch variety. For starch/SMA blends, the starch granules remained dispersed in the SMA phase. The torque during blending, tensile strength, water absorption, storage and loss modulus, and data on biodegradability of the blends are presented. Tensile strength and water absorption correlated well with the torque generated during blending: the higher the torque, the lower the tensile strength and the higher the water absorption. The tensile strength of blends containing SMA decreased when the humidity increased. Fractured surfaces of starch/SMA blends exhibited brittle failure; for the ductile starch/EPMA blends, shear tearing appeared to be the major failure mechanism. For blends containing EPMA, the percentage elongation increased with increased humidity. Dynamic mechanical analysis of the blends showed two sharp peaks for tan δ vs. temperature plot for starch/EPMA plots, but showed a single peak for starch/SMA blends. Starch/EPMA blends had a higher percentage of water aborption that became constant after 20 days. Using the ASTM test method D5902, the starch content in the samples was found to degrade. © 1995 John Wiley & Sons, Inc.     

纳米莫来石填充PP/EPDM共混物的脆韧转变

制备了含纳米莫来石的三元乙丙橡胶(EPDM)和马来酸酐接枝三元乙丙橡胶(EPDM-g-MAH)母料,研究了纳米莫来石对聚丙烯(PP)/EPDM和PP/EPDM-g-MAH共混物脆韧转变的影响。结果表明:纳米莫来石的加入使PP/EPDM和PP/EPDM-g-MAH共混物的脆韧转变提前,尤其在纳米莫来石用KH-550改性后,PP/EPDM共混物发生脆韧转变时EPDM的含量由15%降至10%;在橡胶相含量相同时,加入纳米莫来石后共混物的弹性模量和拉伸强度略有下降,而断裂伸长率显著下降。     

Mechanical properties and morphology of LCP/ABS blends compatibilized with a styrene–maleic anhydride copolymer

A co‐polyester liquid crystalline polymer (LCP) was melt blended with an acrylonitrile–butadiene–styrene copolymer (ABS). LCP fibrils are formed and a distinct skin/core morphology is observed in the injection moulded samples. At higher LCP concentration (50 wt%), phase inversion occurs, where the dispersed LCP phase becomes a co‐continuous phase. While the tensile strength and Young's modulus remain unchanged with increasing LCP content up to 30 wt% LCP, a significant enhancement of the modulus at 50 wt% LCP is observed due to the formation of co‐continuous morphology. The blend modulus is lower than the values predicted by the rule of mixtures, suggesting a poor interface between the LCP droplets and ABS matrix. A copolymer of styrene and maleic anhydride (SMA) was added in the LCP/ABS blends during melt blending. It is observed that SMA has a compatibilizing effect on the blend system and an optimum SMA content exists for mechanical properties enhancement. SMA improves the interfacial adhesion, whereas excess of SMA reduces the LCP fibrillation. Copyright © 2003 Society of Chemical Industry     

柞蚕丝丝素/壳聚糖共混体系的静电纺丝研究

利用六氟异丙醇和三氟乙酸为溶剂,通过静电纺丝制备了不同共混比的柞蚕丝丝素(TSF)/壳聚糖(CS)纳米纤维。研究了TSF/CS共混比对纺丝液黏度、电导率和纤维形貌的影响。结果表明,TSF/CS共混液的电导率随CS含量的增加而增加;随着CS含量的增加(≤15%),共混液的黏度增加缓慢,纤维由转曲的扁平带状逐渐变为圆柱形且直径逐渐降低;当CS含量超过15%时,共混液的黏度随CS含量的增加而显著增大,纤维出现粗细两极分化现象。