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以高熔体强度聚丙烯(PP)和乙烯–辛烯共聚物(POE)为主要原料,利用化学发泡法制备了PP/POE微发泡材料。研究了POE用量对PP/POE微发泡材料发泡性能、力学性能的影响;通过研究PP/POE微发泡材料的动态力学性能、结晶行为、泡孔结构,确定了POE的最佳用量。添加POE能改善微发泡材料的动态力学性能,同时将PP的结晶峰温度提升117.01℃,加快了PP的结晶过程,为PP发泡提供合适的内部条件,有效地减少了发泡时过发泡、并泡现象的产生。当POE质量分数为10%时,PP/POE微发泡材料的综合性能达到最优,其缺口冲击强度达到13.2kJ/m2,相比未添加POE的微发泡材料提升了约158.8%,泡孔平均直径减小到60μm左右,泡孔密度达到最大值,为1.19×106个/cm3。 相似文献
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采用高级流变扩展系统(ARES)研究了聚丙烯(PP)/乙烯-辛烯共聚物共混体系的流变性能,探讨了乙烯-辛烯共聚物含量和 PP 种类对共混体系储能模量、剪切黏度和零切黏度的影响。实验结果显示,PP 结构和 POE 含量对 PP/POE 共混体系的剪切流变性能有显著影响,随着 POE 含量的增加,PP1/POE 共混体系的储能模量和剪切黏度增加的幅度明显小于 PP2/POE 共混体系,PP1/POE 共混体系和 PP2/POE 共混体系的储能模量和剪切黏度增加幅度较大分别发生在 POE 含量为20%~30%和10%~20%,即共混体系发生"脆—韧"转变阶段。PP/POE 共混体系中存在界面滑移现象,且 PP 和 POE 的界面相容性对界面滑移现象影响较大,其中 PP1/POE 的界面滑移比PP2/POE 的界面滑移更加明显。 相似文献
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《塑料工业》2016,(4)
利用多巴胺在固体表面氧化自聚合的特性,通过一种简便易行的方式制备了聚多巴胺表面修饰的纳米二氧化硅改性粒子PD-SiO_2。红外光谱测试表明,聚多巴胺在没有破坏纳米二氧化硅结构的前提下成功黏附其表面。将改性粒子PD-SiO_2与聚丙烯/乙烯-辛烯共聚物(PP/POE)通过熔融共混的方式制备了具有亲水效果的高性能聚丙烯复合材料,并利用红外光谱分析、力学性能、接触角、DSC和扫描电镜(SEM)测试分别研究了复合材料的结构、力学性能、表界面性能、结晶性能和断面形貌。结果表面,PD-SiO_2的加入起到了明显的刚性粒子增强效果,提高了材料的刚性和韧性,提高了PP/POE复合材料的亲水性,降低了PP/POE复合材料的结晶温度,提高了结晶度。 相似文献
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进行了碳酸钙对聚丙烯(PP)的填充改性研究,结果表明:随1%(质量分数)钛酸酯偶联剂表面处理的碳酸钙用量增加,PP/碳酸钙复合材料的拉伸强度、弯曲强度、弯曲模量等逐渐增加,碳酸钙质量分数为20%时,得到了综合性能较好的PP/碳酸钙复合材料;随聚烯烃弹性体(POE)用量增加,PP/碳酸钙/POE复合材料的冲击强度逐渐增加,而拉伸强度、弯曲模量均逐渐降低,5份POE使复合材料达到较好的刚性和韧性的平衡;1份表面光亮剂能使PP/碳酸钙复合材料达到较好的表面光亮度. 相似文献
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《工程塑料应用》2020,(3)
以无规共聚聚丙烯(PP–R)为基料,采用纳米凹凸棒石(APT)和聚烯烃弹性体(POE)协同改性,通过熔融共混法制备出PP–R/POE/APT三元复合材料,研究了APT和POE对PP–R材料的协同改性效果。升温淋洗分级检测结果表明,单纯添加弹性体POE对PP–R进行改性,增加了室温下可溶物的含量,让PP–R复合材料中的分子链分布更加均匀,进而能够增强PP–R材料在室温下的抗冲击性能。结晶性能测试结果表明,APT与弹性体POE协同改性效果比单纯添加弹性体POE的效果明显;添加了2% APT纳米粒子和20% POE弹性体组合后,提高了材料的熔融温度与结晶温度,同时细化了PP–R中的α晶型,有利于提高材料的韧性。 相似文献
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用熔融共混法制备了高密度聚乙烯/聚丙烯(HDPE/PP)和乙烯-辛烯弹性体/高密度聚乙烯/聚丙烯(POE/HDPE/PP)复合材料。通过冲击、弯曲和拉伸测试研究了复合材料的力学性能,采用扫描电镜(SEM)观察了材料的形貌。结果表明,由于HDPE和PP的相容性有限,限制了HDPE对PP综合力学性能的提高;通过添加POE,能改善HDPE/PP共混物的相容性,使HDPE/PP复合材料在保持较高弯曲和拉伸性能的前提下,抗冲击性能获得明显提高。当HDPE/PP的含量比为12/88和POE含量为8wt%时,POE/HDPE/PP三元复合材料的综合力学性能较好。 相似文献
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应用双螺杆挤出机制备了聚丙烯(PP)/聚烯烃弹性体(POE)共混体系和PP/POE/纳米碳酸钙(nano-CaCO3)复合体系,研究了POE用量及nano-CaCO3对PP冲击性能、拉伸性能及弯曲性能的影响。结果表明,随着POE用量的增加,PP/POE共混体系及PP/POE/nano-CaCO3复合体系的冲击强度明显增加;拉伸强度及拉伸模量、弯曲强度及弯曲模量均减小;断裂伸长率及断裂强度亦减小。此外,与PP/POE共混体系相比,PP/POE/nano-CaCO3复合体系的冲击强度、拉伸强度及拉伸模量、弯曲强度及弯曲模量均优于PP/POE共混体系。 相似文献
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以聚丙烯(PP)为基体,植物纤维苎麻(RF)为填料,利用熔融共混法制备了PP/苎麻纤维(PP/RF)复合材料。考察了RF的表面修饰对复合材料性能的影响。通过力学性能测试、微观形貌观察、维卡软化温度检测、线膨胀系数测定以及差示扫描量热仪测试(DSC)等对其性能进行了评估。结果表明,RF的表面修饰可以提高PP/RF复合材料的冲击强度和维卡软化点,并降低线膨胀系数和结晶度,使用碱处理的RF增强复合材料的线膨胀系数最小,马来酸酐接枝乙烯辛烯共聚物(POE g MAH)修饰后的复合材料结晶度最低。 相似文献
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This work was focused on the impact fracture behavior of polypropylene/ethylene-octene copolymer (PP/POE) blends with and
without nucleating agent (NA). The crystallization morphologies of injection-molded-bar were analyzed by polarization optical
microscope and the impact-fractured surface morphologies were characterized carefully through scanning electronic microscope.
Our results show that the addition of 0.2 wt% α/or β-NA induces the great decrease of spherulites diameters companioned with
the dramatically enhancement of PP/POE blend toughness. Virgin PP shows the typical brittle-fractured characteristic during
the whole fracture process. PP/POE shows the less-ductile fracture feature with multiple-craze formation. The addition of
NA into PP/POE blend changes the fractured surface feature from predominantly multiple-craze to predominantly shear yielding
or shear yielding involving materials cavitations and second-crack re-initiation, respectively, indicating the change from
brittle-like fracture mode to ductile fracture mode. The transformation of β → α during the impact process for β-NA nucleated
samples has been observed; however, such transformation is suppressed by the presence of POE. 相似文献
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Surface‐modified MgO nanoparticle enhances the mechanical and direct‐current electrical characteristics of polypropylene/polyolefin elastomer nanodielectrics 下载免费PDF全文
Polypropylene (PP)/polyolefin elastomer (POE) blends and MgO/PP/POE nanocomposites were fabricated by melt blending. The morphology, mechanical, and electrical properties of the nanocomposites were investigated. Scanning electron microscopy showed that the surface‐modified MgO nanoparticles were well dispersed in the polymer matrix at low loadings of less than 3 phr. X‐ray diffraction demonstrated that the crystalline phases of PP in the composites were changed and that the β phase significantly increased. An examination of the electrical properties revealed that the direct‐current (dc) electric breakdown strength and space‐charge suppression effect were remarkably improved by the introduction of the surface‐modified MgO nanoparticles. In addition, obvious enhancements in the tensile modulus and strength were obtained as a result of the synergistic toughening of the POE and MgO nanoparticles. Thus, MgO/PP/POE nanocomposites with enhanced mechanical and electrical properties have great potential to be used as recyclable insulation materials for high‐voltage dc cables with large transmission capacities and high operating temperatures. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 132, 42863. 相似文献
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为提高聚丙烯(PP)材料的热性能和力学性能,选用膨胀型阻燃剂(IFR)对PP/乙烯-辛烯共聚物(POE)共混体系进行阻燃改性,应用双螺杆共混挤出的方法制备了PP/POE/IFR共混复合体系,对共混复合体系的阻燃性能、力学性能、膨胀炭层以及微观相结构进行了研究。结果表明,少量增容剂马来酸酐接枝POE(POE-g-MAH)的加入使得IFR颗粒的分散更加均匀、分散粒径减小,同时颗粒与聚合物基体间的结合更加紧密,从而对共混复合体系的力学和阻燃性能都有明显的提高,特别是提高冲击强度。当PP/POE/IFR/POE-g-MAH配比为80/17/20/3时,共混复合体系的平均热释放速率、热释放速率峰值、比消光面积平均值、总烟释放量较未添加增容剂的共混复合体系(PP/POE/IFR配比为80/20/20)分别下降了22.4%,14.9%,29.2%,21.8%,冲击强度提高了69.6%。 相似文献
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Microstructured and Electro-Assisted High-Temperature Wettability of MgO in Contact with a Silicate Slag-Based on Fayalite 总被引:1,自引:0,他引:1
Christos G. Aneziris Michael Hampel 《International Journal of Applied Ceramic Technology》2008,5(5):469-479
In this work, MgO samples have been microstructured by laser treatment and surfaces with a controlled stripe design have been manufactured. Sessile drop wetting measurements were performed in a special heating microscope by determining horizontal contact angles as well as contact angles as a function of surface inclination angles. In a further step, voltage was applied to ground MgO surfaces and the wetting behavior was registered as a function of the voltage level. Activation energy analysis was conducted for all the experiments. 相似文献
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采用双螺杆挤出机制备了均聚聚丙烯(PPH) /聚烯烃弹性体( POE) 共混物和PPH/POE/滑石粉三元共混体系。使用差示扫描量热仪和万能试验机研究了共混物和复合材料的结晶性能、力学性能和加工性能。结果表明,POE对PPH力学性能和结晶性能有明显的影响,随着POE用量的增加,PP/POE共混物的结晶度明显下降,PPH/POE 共混物的冲击强度明显提高,但拉伸强度显著降低。POE含量为20 %时,冲击强度由2.1 kJ/m2提高到39 kJ/m2,拉伸强度由30 MPa 降低到22MPa。加入滑石粉可以提高PPH/POE共混物的拉伸强度,滑石粉添加量1份时,可使共混物的拉伸强度提高到24 MPa。 相似文献