原位增容PA6/POE共混物流变行为的研究

使用毛细管流变仪研究了PA6/(乙烯/辛烯)共聚物(POE)共混物的流变行为,并对其lgω-lgτ、lgηa-lgγω、lgηa-1/T曲线进行了分析.研究表明,PA6/POE共混物为假塑性流体,其表观粘度随着剪切应力的增加而降低;加入马来酸酐和引发剂使得PA6/POE共混物的表观粘度增大;PA6/POE共混物的粘流活化能随着剪切应力的增大而降低,说明PA6/POE共混物在高剪切应力下可在较宽的温度范围内加工、成型.     

原位增容法制备PA6/EPDM/MMT复合材料流变性能的研究

通过原位增容法制备了PA6/EPDM/MMT三元纳米复合材料,采用熔体质量流动速率试验机和毛细管流变仪研究了PA6及三元纳米复合材料流变行为,并对其lgγω-lgτω、lgηa-lgγω、lgηa-1/T曲线进行了分析。结果表明,在230～245℃及剪切应力为24.5～73.5MPa时,PA6及其三元纳米复合材料均为假塑性流体;EPDM、MMT的加入明显地降低了纯PA6的非牛顿指数n,并且使PA6的黏流活化能ΔE较大幅度的升高,但EPDM/MAH/DCP混合物用量的增加对ΔE的影响不明显。随着EPDM/MAH/DCP用量的增加,复合材料的黏度先增加后减小,EPDM/MAH/DCP用量达到20%时达到最大值。     

PA6/POE/OMMT纳米复合材料的流变行为

使用毛细管流变仪研究了尼龙6/乙烯-辛烯共聚物/有机改性蒙脱土(PA6/POE/OMMT)纳米复合材料的流变行为,并对lgΥω-lgγω、lgηα-lgγω、lgηα-1/T曲线进行了分析.研究结果表明,PA6/POE/OMMT纳米复合材料为假塑性流体,其表观粘度随着剪切应力的增加而降低;OMMT使得PA6/POE纳米...     

相容剂对HDPE/PA6共混体系加工性能和阻隔性能的影响

以高密度聚乙烯接枝马来酸酐(HDPE-g-MAH)为相容剂,制备了高密度聚乙烯/聚酰胺6(HDPE/PA6)共混复合材料,考察了相容剂用量对共混材料加工性能及阻隔性能的影响。结果表明:HDPE-g-MAH作为反应型相容剂,与PA6反应后的生成物提高了PA6与HDPE基体的相容性和分散均匀性,降低了共混物的最大扭矩,促进了HDPE塑化,改善了加工性能;随着相容剂用量的增加,共混物最大扭矩和平衡扭矩均有所提高,说明相容剂用量的增加增强了HDPE与PA6间的相互作用,提高了共混物的黏度,而相间黏结性能的改善,使PA6能以片层结构分散于HDPE树脂中,提高了材料的阻隔性能。共混物对二甲苯的吸收有一饱和值,其阻隔性能具有很好的稳定性。     

HDPE/HDPE-g-MAH/PA11共混物流变行为的研究

以马来酸酐接枝高密度聚乙烯(HDPE-g-MAH)为增容剂,通过熔融共混法制备了HDPE/HDPE-g-MAH/聚酰胺11(PA11)共混物,讨论了增容剂HDPE-g-MAH对共混物流变行为的影响。结果表明:HDPE-g-MAH的加入使共混物熔体对剪切速率的敏感性增强,同时使共混物黏度对温度变化的敏感程度减弱;随着HDPE-g-MAH含量的增加,共混物表观黏度先增加后减小,其含量为2%时共混物黏度最大。     

超支化聚合物对PA6及其纤维性能的影响

将聚己内酰胺(PA6)与超支化聚合物(HBP)共混造粒、纺丝,研究了PA6/HBP共混物的流变性能及共混纤维的力学性能。结果表明:PA6/HBP共混物为非牛顿性假塑性流体,其表观黏度随着剪切速率的增大而减小;随着HBP含量增大,共混物非牛顿流动指数降低,剪切速率上升,加工温度降低;共混物黏流活化能随着HBP含量的增大而增大;PA6/HBP共混物较PA6结晶度提高,球晶明显细化;当w(HBP)为1.0%时,PA6/HBP共混纤维的断裂强度较纯PA6纤维略有降低,随着HBP含量的增加,共混纤维的力学性能明显降低。     

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.     

PA6／HDPE／EVA三元共混改性的研究

研究了PA6/HDPE、PA6/HDPE/EVA共混物的密度、热性能和力学性能。PA6/HDPE/EVA三元共混物的力学性能比PA6/HDPE二元共混物有明显提高。对于拉伸强度,EVA的最佳含量在2～4份。冲击强度随EVA含量的增加而提高,EVA的含量小于5份时,对共混物的硬度几乎没有影响。     

原位增容PA6/POE/EVOH共混物的流变性能研究

采用熔融共混法制备了聚酰胺6/乙烯-1-辛烯共聚物/乙烯-乙烯醇共聚物(PA6/POE/EVOH)共混物,利用毛细管流变仪对共混物的流变行为进行了研究。结果表明:PA6/POE/EVOH共混物为假塑性流体,呈现出切力变稀的现象;EVOH的加入增大了PA6/POE/EVOH共混物的表观黏度和黏流活化能,说明共混物对温度的依赖性较强。     

PP-g-MAH增容PP/玻纤增强PA6共混体系流变性能研究

采用毛细管流变仪,以聚丙烯接枝马来酸酐(PP-g-MAH)为增容剂,研究了PP-g-MAH对PP/玻纤增强聚酰胺6(PA6)共混体系流变性能的影响。结果表明:PP/玻纤增强PA6共混体系为典型的切力变型流体,共混体系的表观黏度均随着剪切速率的增大而降低;随增容剂用量的增加,共混体系的表观黏度提高,非牛顿指数n先增大后减小,黏流活化能ΔEη和结构黏度指数Δη先减小后增大;增容剂用量为5%时,共混体系的非牛顿指数出现极大值,黏流活化能和结构黏度指数出现极小值。     

工艺条件对HDPE／PA—6共混体系形态结构影响的研究

通过测试ＨＤＰＥ、ＰＡ－６的流变性能和对共混物进行显微镜法（ＰＣＭ）分析,研究了加工温度和剪切速率等工艺条件对ＨＤＰＥ／ＰＡ－６共混形态结构的影响。结果表明：改变加工温度可以调节ＨＤＰＥ／ＰＡ－６共混组成粘度比。ＰＡ－６和ＨＤＰＥ的粘讧比较大时,ＰＡ－６相呈层状分布结构,剪切作用有利于共混体系两相的分散,剪切速率过低易使ＰＡ－６相区尺寸大,分散不均匀。较高的剪切速率使ＰＡ－６相尺寸减小,分散更均匀     

Rheological and Mechanical Properties of LDPE/HDPE Blends

Melt rheology and mechanical properties of binary blend of low-density polyethylene (LDPE) and high-density polyethylene (HDPE) have been investigated. Four different wt fractions of blends containing LDPE/HDPE (20/80, 40/60, 60/40, and 80/20) were prepared. Cole-Cole plots [storage melt viscosity (η′) vs. loss melt viscosity (η″)] and relation between storage melt viscosity (η′) with frequency (ω) and blend composition were constructed. Miscibility of blends was established from rheological data. Impact strength of the blends increased with increasing LDPE concentration, whereas tensile strength shows the opposite trends. Percentages of the crystallinity of the blends were calculated by both the differential scanning calorimetry and wide-angle X-ray scattering methods, which show that the percentage of crystallinity decreased with increasing LDPE concentration, but the rate of crystallization of HDPE phase was unaffected.     

PA1010/TPU共混物流变性能的研究

以尼龙1010(PA1010)为基体，以聚酯型热塑性聚氨酯弹性体(TPU)为增韧剂，采用Haake PTW16／25p型双螺杆挤出机制备了PA1010／TPU共混增韧尼龙材料。测试了PA1010／TPU共混物的表观粘度、非牛顿指数等流变参数，并重点讨论了其流变性能。实验结果表明：共混物熔体的表现粘度随剪切速率的增大而降低，非牛顿指数小于1，符合假塑性流体流动规律。此外共混物的表观粘度随着组成和温度的变化呈现了一种极为特殊的变化行为。即在相同温度下，共混物的表观粘度随着TPU含量增加而增加；在相同组成下，共混物的表观粘度随着温度升高而升高。     

PP/HDPE共混体系毛细管流变性能研究

用毛细管流变仪对以马来酸酐接枝聚丙烯(PP-g-MAH)为相容剂的聚丙烯/高密度聚乙烯(PP/HDPE)共混体系的流变性能进行研究。研究发现,PP/HDPE共混体系属于假塑性流体;随着剪切速率的增加,表观黏度下降;PP-g-MAH的加入降低了共混体系的表观黏度;HDPE与PP的非牛顿指数在低剪切速率区与适宜温度下适用于幂律方程的经验公式;HDPE与PP共混后,HDPE含量越低,体系出现壁面滑移的临界剪切速率越高,可加工性能越好。     

In‐process ultrasonic measurements of orientation and disorientation relaxation of high‐density polyethylene/polyamide‐6 composites with compatibilizer

The relaxation processes of orientation and disorientation of melts of high‐density polyethylene (HDPE) and polyamide‐6 (PA6) blends compatibilized with a compatibilizer precursor (CP) of HDPE‐grafted maleic anhydride (HDPE‐g‐MAH) were investigated in a restricted channel using real‐time ultrasonic technique. The experimental results showed that the evolution of ultrasonic velocity of HDPE/PA6 blends during the orientation or disorientation processes could be described by the exponential equation from which the maximum orientation degree and relaxation time could be obtained. Subsequently, the effects of CP on the relaxation processes of orientation and disorientation were studied. In addition, the relations of the CP content and the morphology and viscosity were investigated by scanning electron microscope analysis and rheological tests. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

阻隔改性组分PA6对HDPE/PA6合金性能的影响

研究了ＨＤＰＥ／ＰＡ６合金阻隔改性组分ＰＡ６的筛选及其含量对该合金阻隔性能和力学性能的影响。结果表明，在增容剂的条件下，具有适当粘度的ＰＡ６能与ＨＤＰＥ共混制得宏观均匀的合金材料；ＰＡ６含量对共混体系的阻隔性能影响显著；当ＰＡ６占３０份以上时，ＨＤＰＥ／ＰＡ６合金阻隔非极性溶剂的性能大幅度提高，同时，ＰＡ６的加入对合金有一定的增强作用。     

Effect of core‐shell morphology evolution on the rheology,crystallization, and mechanical properties of PA6/EPDM‐g‐MA/HDPE ternary blend

In this article, polyamide 6 (PA6), maleic anhydride grafted ethylene‐propylene‐diene monomer (EPDM‐g‐MA), high‐density polyethylene (HDPE) were simultaneously added into an internal mixer to melt‐mixing for different periods. The relationship between morphology and rheological behaviors, crystallization, mechanical properties of PA6/EPDM‐g‐MA/HDPE blends were studied. The phase morphology observation revealed that PA6/EPDM‐g‐MA/HDPE (70/15/15 wt %) blend is constituted from PA6 matrix in which is dispersed core‐shell droplets of HDPE core encapsulated by EPDM‐g‐MA phase and indicated that the mixing time played a crucial role on the evolution of the core‐shell morphology. Rheological measurement manifested that the complex viscosity and storage modulus of ternary blends were notable higher than the pure polymer blends and binary blends which ascribed different phase morphology. Moreover, the maximum notched impact strength of PA6/EPDM‐g‐MA/HDPE blend was 80.7 KJ/m² and this value was 10–11 times higher than that of pure PA6. Particularly, differential scanning calorimetry results indicated that the bulk crystallization temperature of HDPE (114.6°C) was partly weakened and a new crystallization peak appeared at a lower temperature of around 102.2°C as a result of co‐crystal of HDPE and EPDM‐g‐MA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013