磷酸酯盐成核剂对聚丙烯性能的影响

以均聚聚丙烯(PP)为基体树脂,通过添加磷酸酯盐类成核剂TMP-1等改性方式,研究了该成核剂在不同添加量下对PP弯曲模量、拉伸屈服强度、悬臂梁缺口冲击强度以及热变形温度等性能的影响,通过差示扫描量热仪(DSC)与带可程序升降温控制热台的偏光显微镜(POM)考察了成核剂对PP结晶性能的影响。力学性能测试及偏光显微镜微观观察表明,磷酸酯盐类成核剂TMP-1可以有效提高PP的弯曲模量、拉伸屈服强度、热变形温度以及结晶速度,但是,悬臂梁缺口冲击强度则会明显下降。同时,测试数据表明,当成核剂TMP-1的添加量为0. 05%时,弯曲模量可以达到最大值(2 253. 82 MPa),与未添加成核剂的纯树脂相比,弯曲模量提高了81. 1%。     

云母与成核剂复配改性PP

采用云母和成核剂填充改性聚丙烯(PP),研究了复合材料的力学性能、结晶性能及耐热性能。结果表明:云母可有效提高PP的弯曲强度及模量、悬臂梁缺口冲击强度和耐热性能;少量成核剂NA11和表面活性剂硬脂酸钙可使PP/云母复合材料的拉伸强度、弯曲强度、弯曲模量及悬臂梁缺口冲击强度较纯PP分别提高10.4%,32.9%,92.6%,9.2%,热变形温度由纯PP的105℃提高到135℃;云母及NA11对PP具有异相成核作用,复合材料的结晶温度明显提高,晶粒细化、致密。     

玄武岩纤维增强聚丙烯复合材料性能研究

以聚丙烯(PP)树脂为基体,加入玄武岩纤维(BF)和相关助剂,通过双螺杆挤出机熔融共混制得相应复合材料。考查相容剂对PP/BF复合材料性能影响、对PP/BF复合材料和PP/玻璃纤维(GF)复合材料力学性能、微观形貌和耐热氧老化等性能进行对比。通过实验数据分析,加入相容剂后,拉伸强度提高126.8%,弯曲强度提高223.8%,弯曲弹性模量提高119.9%,悬臂梁缺口冲击强度提高223.2%。在同样质量配比下,PP/BF复合材料较PP/GF复合材料拉伸强度提高9.8%,弯曲强度提高11.0%,弯曲弹性模量提高5.8%,悬臂梁缺口冲击强度降低10.7%。从微观电镜分析,加入相容剂可明显改善纤维与PP基材界面浸润程度。另外,BF比GF更易使复合材料老化,常规热氧老化剂1010和168对纤维增强PP类材料耐老化效果并不好,用等量自制热氧老化剂可解决此问题。     

等通道转角挤压加工对聚丙烯性能的影响

研究了模压成型聚丙烯(PP)经等通道转角挤压(ECAE)加工后的性能。研究表明,一次和二次ECAE加工对PP结晶度和密度的影响较小。PP经一次和二次ECAE加工后其缺口冲击强度均有所提高,且经二次A路径的ECAE加工后试样的缺口冲击强度显著提高,约为PP的18倍;经C路径的二次ECAE加工后试样为各向同性材料,其缺口冲击强度较PP有所提高,拉伸强度下降,断裂伸长率提高,表现出很好的延伸性。     

GF增强PP复合材料的尺寸稳定性与力学性能

研究了马来酸酐接枝聚丙烯(PP-g-MAH)含量及玻璃纤维(GF)含量对GF增强聚丙烯(PP)复合材料尺寸稳定性与力学性能的影响。结果表明,加入PP-g-MAH后,复合材料的线性膨胀系数和收缩率下降,结晶度、拉伸强度、弯曲强度和悬臂梁缺口冲击强度提高,但断裂伸长率下降。相比不添加PP-g-MAH的复合材料,当PP-g-MAH质量分数达到6%时,复合材料在流道方向上的线性膨胀系数从29.88μm/(m·℃)降低至24.93μm/(m·℃),在流道方向上的收缩率从0.20%下降至0.18%,拉伸强度、弯曲强度和悬臂梁缺口冲击强度基本达到最大值,分别提高130.18%,96.52%和49.20%;随着GF质量分数的增加,复合材料的线性膨胀系数和收缩率均显著下降,拉伸强度、弯曲强度和悬臂梁缺口冲击强度提高,而断裂伸长率和结晶度下降。相比不添加GF的复合材料,当GF质量分数为40%时,复合材料在流道方向上的线性膨胀系数从101.30μm/(m·℃)降低至18.08μm/(m·℃),在流道方向上的收缩率从1.43%下降至0.08%,结晶度从45.05%下降至23.96%,拉伸强度、弯曲强度和悬臂梁缺口冲击强度分别提高168.87%,306.40%和129.52%。     

EVAL-g-MANa离聚物对PP/EVA热塑性硫化橡胶性能的影响

将皂化乙烯-乙酸乙烯共聚物接枝马来酸钠(EVAL-g-MANa)离聚物加入聚丙烯(PP)/乙烯-乙酸乙烯共聚物(EVA)热塑性硫化橡胶中,探讨了EVAL-g-MANa对PP/EVA热塑性硫化橡胶力学性能、加工性能及微观结构的影响。结果表明:EVAL-g-MANa可作为PP/EVA热塑性硫化橡胶的相容剂。当EVAL-g-MANa用量为6 phr时,PP/EVA热塑性硫化橡胶的拉伸强度、悬臂梁缺口冲击强度、弯曲应力分别提高13.79%,23.85%,14.95%,同时,熔体流动速率提高32.56%。     

丙烯酸改性卤锑阻燃PP的力学性能

在过氧化二异丙苯(DCF)存在或不存在条件下,制备了丙烯酸(AA)改性Sb2O3／聚丙烯(PP)母料、十溴联苯醚／PP母料及其相应的卤锑阻燃PP。研究了Sb2O3、十溴联苯醚和不同含量卤锑阻燃剂对PP力学性能的影响。结果表明,随Sb2O3含量增加,PP的拉伸和弯曲性能提高,缺口冲击强度降低。对于改性阻燃PP,无DCP时,加入AA有利于阻燃PP拉伸强度提高。但对其他力学性能影响不大。添加DCP提高了PP的弯曲强度。但AA用量高时,缺口冲击强度降低。AA改性阻燃PP的力学性能随着DCP用量增加而降低,尤其缺口冲击强度。退火处理使阻燃PP力学性能提高。     

PP/间同1,2-聚丁二烯的物理力学性能

添加不同质量分数的间同1,2-聚丁二烯(sPB)热塑性弹性体对聚丙烯(PP)共混改性,研究了共混体系的物理力学性能。PP与sPB结构相似,有良好的相容性,随着w(sPB)从0增至40%,共混体系的屈服拉伸强度、弯曲模量及耐热性有所降低;悬臂梁冲击强度增加,且常温悬臂梁冲击强度增幅较大,但低温悬臂梁冲击强度增加较少;断裂伸长率和熔体流动速率先增加后减少。     

β晶型聚丙烯的结构与性能

采用NT-A和NT-D成核剂制备了β晶型聚丙烯(β-PP),研究其熔融及结晶特性、结晶形态和力学性能.结果发现,NT-A和NT-D成核剂均使聚丙烯(PP)球晶细化,提高PP的拉伸强度、拉伸断裂应变和悬臂梁缺口冲击强度,但NT-D的β成核效果更好,其改性PP的β晶型质量分数可达80%～90%,悬臂梁缺口冲击强度是纯PP的3倍多.注射成型PP样条具有明显的皮芯层结构,纯PP样条的皮层和芯层仅含有α晶型.且结晶度差异不大;β-PP样条的皮层仅有α晶型,而芯层除α晶型外还有β晶型.     

PP/改性高岭土复合材料的制备及性能

采用液态三元乙丙橡胶(LEPDM)对高岭土进行表面改性，然后与聚丙烯(PP)熔融共混，制得了PP/改性高岭土复合材料，采用氧指数测定仪、熔体流动速率仪(MFR)和扫描电子显微镜(SEM)等对比分析了高岭土和改性高岭土对PP力学性能、加工性能、阻燃性能和微观形貌的影响。结果表明：高岭土及改性高岭土均会改善PP的力学性能、加工性能和阻燃性能。当填料含量相同时，PP/改性高岭土复合材料的拉伸强度、缺口冲击强度和加工性能均优于PP/高岭土复合材料，PP/高岭土复合材料的阻燃性能和弹性模量均优于PP/改性高岭土复合材料。当改性高岭土质量分数为10%时，PP/改性高岭土复合材料的缺口冲击强度和MFR均达到最大，分别为12.63 kJ/m²和1.75 g/10 min。     

Physical and Mechanical Properties of Polypropylene Reinforced with Fe Particles

ABSTRACT

The physical and mechanical properties of Polypropylene (PP) and Fe-PP polymer composites containing 5, 10, and 15 vol% Fe were investigated experimentally. After preparing PP and Fe–PP polymer composites with a twin screw extruder and injection molding, the following properties were determined: yield and tensile strength, the modulus of elasticity, % elongation, hardness (Shore D), Izod impact strength (notched), melt flow index (MFI), Vicat softening point, Heat deflection temperature (HDT), and melting temperature (Tm) of PP and metal-polymer composites. As compared to PP, It was found that by increasing the vol% of Fe in PP, notched Izod impact strength, yield and tensile strength, and % elongation decreased. On the other hand, the modulus of elasticity, hardness, MFI, vicat softening point, and HDT values increased with the amount of iron.     

Mechanical Properties of Polymers Filled with Iron Powder

Mechanical properties of metal-polymer matrix composites were investigated experimentally. High density polyethylene (HDPE), polypropylene (PP), and polystyrene (PS) were used as the polymer matrix and Fe powder in 5, 10, and 15 vol% was used as the metal. The modulus of elasticity, yield and tensile strength, % elongation, Izod notched impact strength, Shore D hardness, and fracture surfaces of the composites were determined. It was found that vol% Fe reduced the Izod impact strength of HDPE much more than that of PP and PS, while Fe powder increased the hardness of HDPE more than that of PP and PS. Among the composites, PS-Fe composites had higher yield, tensile strength and modulus of elasticity than HDPE-Fe and PP-Fe composites. However, % elongation of PS-Fe composites was lower than that of the other composites. In addition, HDPE- and PP-based composites exhibited ductile type fracture, while PS-Fe composites exhibited brittle type fracture.     

The physical and mechanical properties of polymer composites filled with Fe‐powder

In this study, the effect of Fe powder on the physical and mechanical properties of high density polyethylene (HDPE) was investigated experimentally. HDPE and HDPE containing 5, 10, and 15 vol % Fe metal–polymer composites were prepared with a twin screw extruder and injection molding. After this, fracture surface, the modulus of elasticity, yield and tensile strength, % elongation, Izod impact strength (notched), hardness (Shore D), Vicat softening point, heat deflection temperature (HDT), melt flow index (MFI), and melting temperature (T_m) were determined, for each sample. When the physical and mechanical properties of the composites were compared with the results of unfilled HDPE, it was found that the yield and tensile strength, % elongation, and Izod impact strength of HDPE decreased with the vol % of Fe. As compared with the tensile strength and % elongation of unfilled HDPE, tensile strength and % elongation of 15 vol % Fe filled HDPE were lower, about 17.40% and 94.75% respectively. On the other hand, addition of Fe into HDPE increased the modulus of elasticity, hardness, Vicat softening, MFI, and HDT values, such that 15 vol % Fe increased the modulus of elasticity to about 48%. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Polypropylene and potato starch biocomposites: Physicomechanical and thermal properties

To determine the possibility of using starch as biodegradable filler in the thermoplastic polymer matrix, starch‐filled polypropylene (PP) composites were prepared by extrusion of PP resin with 5, 10, 15, and 20 wt % of potato starch in corotating twin‐screw extruder. The extruded strands were cut into pellets and injection molded to make test specimens. These specimens were tested for physicomechanical properties such as tensile and flexural properties, Izod impact strength, density, and water absorption. These PP composites were further characterized by melt flow index (MFI), vicat softening point (VSP), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) techniques. It was found that, with increase in starch content, tensile modulus, flexural strength, and flexural modulus of the PP composites increased along with the increase in moisture, water absorption, and density, while retaining the VSP; but, tensile strength and elongation, impact strength, hardness, and MFI of the PP composites also decreased. DSC analysis of the PP composite revealed the reduction in melting temperature, heat of fusion, and percentage of crystallization of PP with increase in starch content. Similarly, TGA traces display enhanced thermal degradability for PP as starch content increases. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

PP／废旧橡胶／SBS复合材料的制备和力学性能研究

通过磨盘型力化学反应器制备PP/废旧橡胶(WTR)复合粉体，然后与SKS共混制备PP/WTR/SBS复合材料。研究了材料的力学性能、微观结构和共混物的加工性质。结果表明：当SBS添加量在20％～25％时，PP/WTR/SBS复合材料的力学性能较PP/WTR有了很大的提高，当SBS用量为25％时，断裂伸长率提高了365％，冲击强度提高了73．2％，而体系的拉伸强度基本不变。复合材料冲击断面的形貌和复合体系流变性能研究结果表明：磨盘碾磨可有效改善各组分间的混合性能，提高相容性并有效改善材料的加工性能。     

聚丙烯/超高摩尔质量聚乙烯共混物的结构与性能研究

研究了不同物料比和加工工艺对聚丙烯（PP）／超高摩尔质量聚乙烯（UHMWPE）共混体系性能的影响。结果表明，PP／UHMWPE共混体系具有比音一组分更高的冲击性能，当体系中UHMWPE的质量分数为60％时，共混物的冲击强度高达101kJ/m^2，分别是PP的1．8倍和UHMWPE的1．3倍，将UHMWPE加入PP中可明显降低PP的摩擦系数，提高其耐磨性，而适量UHMWPE加入PP中，对UHMWPE的耐磨性能无不良影响，对以PP为连续相的共混体系，混炼方式对共混物的性能影响大，偏光显微镜分析表明，当PP／UHMWPE共混体系中UHMWPE的质量分数大于40％时，就很难观察到明显的PP大球晶结构，DSC分析显示，PP／UHMWPE共混物出现了两纯组分熔点的结晶熔融峰，PP／UHMWPE为热力学不相容体系。     

汽车保险杠专用聚丙烯树脂的开发

在Innovene工艺聚丙烯(PP)装置上成功开发了汽车保险杠专用PP树脂K9015,产品主要性能指标达到要求:熔体流动速率为17.9 g/10 min,弯曲模量为660 MPa,拉伸屈服强度为17.7 MPa,悬臂梁缺口冲击强度(-20℃)为660 MPa,热变形温度(0.45 MPa)为92℃。     

HDPE及增韧HDPE的力学性能与测试条件的关系

于23℃时,研究了拉伸、弯曲速度及试样缺口剩余宽度对高密度聚乙烯(HDPE)、HDPE/弹性体、HDPE/E型增韧母料(E-TMB)的拉伸、弯曲及冲击强度等力学性能的影响。结果表明,所研究的测试条件对这三种材料力学性能影响的程度不同:对于这三种材料,均是拉伸速度对拉伸屈服应力、弹性模量影响的程度较小,对断裂伸长率影响的程度较大,弯曲速度对弯曲弹性模量、弯曲强度影响的程度较大;三种材料中,拉伸速度对断裂伸长率影响程度最大的是HDPE/弹性体,最小的是HDPE/E-TMB,弯曲速度对弯曲弹性模量、弯曲强度影响程度最大的是HDPE/E-TMB,最小的是HDPE/弹性体;随外力作用速度增大性能并非匀速变化,对不同的材料、不同的性能有相应的敏感区;试样缺口剩余宽度对HDPE/E-TMB的悬臂梁缺口冲击强度影响程度较大,而且缺口剩余宽度由7.8mm增加到8.0mm是影响的敏感区,对HDPE、HDPE/弹性体的影响的程度很小。     

PFPA1212/SEBS-g-MAH共混合金力学性能和微观结构的研究

制备了石油发酵尼龙1212／SEBS－g-MAH共混合,工对其力学性能和微观结构进行了研究。结果表明，随着增韧剂含量的增加，共混合金的制品冲击强度显著提高，当增韧剂含量为25％时，缺口冲击强度为61.26kJ/m^2，是纯尼龙1212的15倍，拉伸强度保持率是纯尼龙1212的90％。微观结构研究表明，尼龙1212的断裂属于韧性断裂，增韧后的尼龙1212制品冲击断面有明显的应力发白现象，冲击强度提高的主要原因在于应力集中点的增多。