纳米CaCO3填充ABS/PP合金复合物研究

通过熔融共混使纳米CaCO3粒子周围包覆上一层TPE橡胶,制备出纳米CaCO3母料,用其与PP、ABS共混复合制备出ABS/PP合金纳米填料复合物.该复合材料力学性能及熔体流动性能测试结果表明,纳米CaCO3含量在试验用量范围内,ABS纳米CaCO3复合物的拉伸强度随填料含量的增加而增加,当母料含量为17%,母料中纳米CaCO3填料含量为60%左右时有较佳的冲击性能;ABS/PP纳米CaCO3复合物在PP含量9%～10%时有最好的拉伸强度和冲击强度;纳米CaCO3填料含量对复合物的拉伸强度影响不大,随其用量增加对冲击强度有明显的提高;熔体流动性能在PP含量10%左右时达最大,但随填料含量增加而下降.     

纳米CaCO3/EPO/PP复合材料性能与结构的研究

研究了纳米CaCO3／EPO／PP复合材料的力学性能、熔体流变性能及纳米CaCO3粒子在PP基体中的分散状况。结果表明：弹性体EPO对PP有很好的增韧效果，当EPO用量为4份时，PP从脆性断裂转变成韧性断裂；当EPO用量为10份时，PP复合材料的室温和低温缺口冲击强度均有大幅度的提高。在EPO／PP复合材料中加入纳米CaCO3不仅可以显著提高复合材料的室温和低温缺口冲击强度，而且可显著提高复合材料的弯曲弹性模量和MFR，改善复合材料的加工流动性能；纳米CaCO3粒子在PP中达到了纳米级分散。     

高流动性PP／POE／纳米CaCO3复合材料的研制

利用双螺杆挤出机，通过熔融共混工艺制备了聚丙烯(PP)／聚烯烃热塑性弹性体(POE)／纳米CaCO3复合材料。利用扫描电子显微镜(SEM)观察了不同体系的形态，结果显示：纳米CaCO3和POE在PP／POE／nano-CaCO3中互相促进分布及均化。冲击试验结果表明：PP／POE／nano-CaCO3体系的缺口冲击强度较PP／POE、PP／nano-CaCO3和纯PP分别提高了65％，107％和178％。熔体流动速率测试显示：纳米CaCO3在PP／POE／nano-CaCO3中具有提高体系流动性的作用。     

PP／SBS／纳米CaCO3复合材料结构与性能研究

研究了PP/SBS/纳米CaCO3复合材料的力学性能以及SBS分散相颗粒和纳米CaCO3粒子在PP基体中的分散状况。结果表明,纳米CaCO3粒子的加入使复合材料的缺口冲击强度、弯曲弹性模量、拉伸强度均得到提高。透射电镜观察发现,纳米CaCO3粒子的加入使复合体系的熔体黏度增大,对弹性体SBS的分散起到剪切细化、均化的作用,从而起到协同增韧效应。     

无机填料/PP复合材料的力学性能和加工性能

研究无机填料(碳酸钙(CaCO3)、玻璃微珠(GB)和硫酸钙晶须(CSW))对聚丙烯(PP)力学性能和加工性能的影响.SEM观察PP复合材料冲击缺口的断面微观形貌和无机填料在PP基体中的分散情况.结果表明:当CSW舍量为6份时,PP/CSW复合材料的缺口冲击强度达到最大值5.9 kJ/m2.当无机填料含量为6份时,PP/CaCO3、PP/GB和PP/CSW复合材料的拉伸强度达到最大值.随着CaCO3、GB和CSW含量的增加,PP复合材料的加工平衡扭矩逐渐下降.     

添加剂对超细碳酸钙改性聚丙烯的影响研究

研究了β结晶成核剂和交联剂与超细碳酸钙共用时对聚丙烯的改性效果,结果表明,用0 5%β结晶成核剂与10%超细CaCO3改性PP比超细CaCO3改性PP的冲击强度提高125%;当用2%交联剂SJ 1时,在10%含量超细CaCO3下拉伸强度最高;在5%含量超细CaCO3下冲击强度达最高,相比用单一的超细CaCO3改性PP冲击强度提高80%。将包覆聚合物的超细碳酸钙和接枝聚丙烯用于PP改性时,其最佳条件为:填料/包覆聚合物比10∶1,接枝聚丙烯含量10%,复合填料含量7 5%,相比未包覆聚合物的超细CaCO3填充PP的冲击强度提高20%,填料用量增加50%。     

CaCO3粒子及其增韧母料对聚丙烯材料力学性能的影响

采用扫描电镜、红外光谱和材料力学性能试验等方法研究了表面处理剂品种、CaCO3粒径及含量对均聚PP／CaCO3、共聚PP／CaCO3和PP／弹性体／CaCO3共混材料力学性能的影响。结果表明，采用平均粒径在1．0μm左右并经端噁唑啉聚醚、烷氧焦磷酸酯型钛酸酯等复合处理的CaCO3或其增韧母料增韧PP，可使均聚PP、共聚PP的缺口冲击强度提高至2．5～3倍，弯曲模量提高至1．2～1．4倍，可以在较少的弹性体用量条件下较大幅度地提高PP/弹性体共混材料的缺口冲击强度，并同时保持较高的弯曲模量和熔体流动性。红外光谱和扫描电镜分析表明，端噁唑啉聚醚等复合偶联助剂在CaCO3表面的作用及其弹性包覆层的形成是加强界面相的粘结、缓冲基体成型收缩应力、减少界面处微裂缝形成和提高材料缺口冲击强度的关键。     

聚丙烯/轻质CaCO_3复合材料的力学性能研究

采用熔融共混的方法制备了PP/CaCO3复合材料,并研究了轻质CaCO3的表面处理、含量及粒径对材料的拉伸强度和缺口冲击强度两大主要力学性能的影响,着重对实验结果作了科学的理论分析。实验结果表明,钛酸酯类偶联剂能很好地改善CaCO3粒子与PP基体的界面相容性,从而使复合材料的力学性能提高;经表面处理后的超细轻质CaCO3(纳米级)所填充复合材料的拉伸强度和缺口冲击强度明显优于普通轻质CaCO3(微米级);而且处理后的纳米级CaCO3在填充量为10%时对PP的增强增韧效果最佳。     

CacO3在PP和PP/mPE共混物基体中的作用比较

研究CaCO3填料在取丙烯（PP）和茂金属聚乙烯（mPE)弹性体增韧PP共混物（PP／mPE)2种基体中的不同作用。结果表明：在PP基体中，填料显著提高其刚性，而在共混物基体中，由于弹性体的存在，填料的增强作用减弱；弹性体能够改善填料粒子和基体的界面粘合，增大弹性体分散相的尺寸，使PP/mPE共混物的拉伸断裂韧性提高。低温下（－30℃）的Charpy缺口冲击实验表明：少量的CaCO3即可导致PP/mPE体系冲击强度的迅速下降。     

聚丙烯/弹性体/纳米CaCO3复合体系

研究了聚丙烯（PP）／弹性体和PP／弹性体／纳米CaCO3两种复合体系。结果表明，弹性体的加入使体系的冲击强度有很大提高，而拉伸和弯曲强度明显下降；添加8 phr左右的纳米CaCO3，体系的拉伸强度和弯曲强度得到较大提高。通过扫描电子显微镜观察冲击试样断面的形貌，可以很好地解释力学性能的变化。     

Single screw extrusion compounding of particulate filled thermoplastics: State of dispersion and its influence on impact properties

The compounding of calcium carbonate filled polypropylene (PP) is discussed with reference to a single-screw extruder and variants of mixing sections. The mixing section on the screw is exchangeable, and two dispersive mixing elements, namely the Zorro and the Maddock elements, were used. The calcium carbonate was surface treated with a liquid titanate coupling agent (LICA12). The impact strength was measured by a notched Izod impact tester with specimens having a U-shaped sharp notch. The fracture toughness for the PP homopolymer and the filled composites was determined using fracture mechanics principles. The results were correlated with the state of dispersion of the calcium carbonate filler. The effects of filler concentration and surface treatment were examined as well. Correlation between state of dispersion and impact properties for calcium carbonate filled PP was obtained. We also investigated the effect of various mixing elements on the state of dispersion. The experimental results indicate that good dispersion would improve the impact properties of the polymer matrix, but only at moderate filler loading. © 1996 John Wiley & Sons, Inc.     

Influence of the incorporation of fine calcium carbonate particles on the impact strength of polypropylene/polystyrene‐block‐poly(ethylene butene)‐block‐polystyrene blends

The Izod impact strength of two kinds of ternary composites was investigated. One consisted of polypropylene (PP), the triblock copolymer polystyrene‐block‐poly(ethylene butene)‐block‐polystyrene (SEBS), and calcium carbonate (CaCO₃) particles, and the other consisted of PP, carboxylated SEBS (C‐SEBS), and CaCO₃ particles. The mean size of the CaCO₃ particles was about 160 nm. According to scanning electron microscopy observations, the composite with SEBS showed a morphology in which SEBS domains and CaCO₃ particles were independently dispersed in the PP matrix. On the other hand, the composite with C‐SEBS showed a morphology in which CaCO₃ particles were encapsulated by C‐SEBS; that is, a core–shell structure was formed. The Izod impact strength of the composite with SEBS was higher than that of the composite with C‐SEBS and the PP/SEBS and PP/C‐SEBS binary blends. According to observations of the fractured surface, the stress‐whitened area was larger in the composite with SEBS than in the composite with C‐SEBS and the PP/SEBS and PP/C‐SEBS binary blends. The toughening mechanism of the composite, using nanometer‐sized CaCO₃ particles in combination with SEBS, was examined. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

The toughening mechanism of polypropylene/calcium carbonate nanocomposites

The toughening mechanism of polypropylene (PP) filled with calcium carbonate (CaCO₃) nanoparticles is described. In a previous study (Macromolecule 2008;41:9204), we observed that intensive ligament-stretching following debonding of nanoparticles was responsible for the significant improvement in the impact toughness of the annealed PP/CaCO₃ nanocomposites. Furthermore, we hypothesized that strong ligaments, which have high fracture stresses, are needed to stabilize the crack-initiation process and to increase the energy dissipation in the crack-initiation stage. In this study, we used a high-molecular-weight PP to test this hypothesis because strong ligaments could be created from this high-molecular-weight PP. The notched Izod impact strength of the nanocomposites containing the high-molecular-weight PP and 20 wt% CaCO₃ nanoparticles with a monolayer coating of stearic acid was measured to be about 370 J/m, whereas the impact strength of the unfilled PP was 50 J/m. The size of the plastic deformation zone was found to be dependent on the molecular weight of the PP matrix because the strong ligaments of the high-molecular-weight PP enabled the expansion of the plastic deformation zone, leading to a considerable increase in the impact strength. The synergic effect of the high-molecular-weight PP and the monolayer-coated nanoparticles produced nanocomposites with high impact strength, which is much greater than the inherent impact strength of the unfilled polymer. In addition, the effect of the high-molecular-weight PP on the dispersion of the nanoparticles was investigated.     

无卤阻燃PP／APP／PTP／PER复合材料的力学性能

采用多聚磷酸铵/含磷三嗪环聚合物/季戊四醇(APP/PTP/PER)体系制备了阻燃聚丙烯(PP)材料,考察了PTP及其阻燃系统的用量对阻燃PP力学性能的影响。结果表明,APP/PER使PP的缺口冲击强度和弯曲模量提高,拉伸强度有所降低,断裂伸长率下降。PTP对PP的缺口冲击强度和弯曲模量影响不大,拉伸强度有所降低,断裂伸长率下降。当加入29%APP/PER/PTP时,缺口冲击强度和弯曲模量分别比纯PP提高了62.0%和14.3%,拉伸强度和断裂伸长率分别下降了13.9%和91.0%。     

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.     

聚丙烯／碳酸钙复合材料的研制

文章以注塑级PP为基础料,以1250目碳酸钙对其进行填充改性,采用钛酸酯偶联剂对碳酸钙进行表面处理可得到活化碳酸钙,随活化碳酸钙添加量增加,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。以POE对PP／碳酸钙复合材料进行增韧改性,可使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。表面改性剂TAS-2能够明显地改善PP／碳酸钙复合材料的表面光滑性。     

天然胶乳包覆交联聚苯乙烯刚性粒子改性聚丙烯的研究

将天然胶乳包覆到交联聚苯乙烯刚性粒子（N-XPS）上，探讨了N-XPS和包覆剂用量对N-XPS／PP复合材料性能的影响，结果表明：当包覆剂用量为XPS的20％，N—XPS用量为PP的3％时，复合材料的弯曲强度提高30％，简支梁与悬臂梁缺口冲击强度分别提高68％和88％。偏光显微镜观察到加入N-XPS的PP晶粒细化、界面模糊，这一事实证明了N—XPS粒子与PP有好的相容性和诱导结晶成核作用。转矩流变仪测试结果表明：随N—XPS用量的增加，复合材料加料熔融的最大扭矩及物料最低温度有明显的下降，物料达最低温度后，温度增长速率减慢，130s后，温度增长的速率呈上升趋势。     

Impact‐toughening mechanisms of calcium carbonate‐reinforced polypropylene nanocomposite

The impact fracture mechanisms of polypropylene (PP), containing 9.2 vol % of calcium carbonate (CaCO₃) nanoparticles, were investigated using optical microscopy and transmission electron microscopy. The incorporation of CaCO₃ nanoparticles reduces the size of spherulites and induces the formation of β‐phase crystallites, which leads to a more ductile PP matrix. Double‐notch four‐point bending (DN‐4PB) Charpy impact specimens and notched Izod impact specimens were utilized to study the fracture mechanism(s) responsible for the observed toughening effect. A detailed investigation reveals that the CaCO₃ nanoparticles act as stress concentrators to initiate massive crazes, followed by shear banding in PP matrix. These toughening mechanisms are responsible for the observed, improved impact strength. A comparison of the fracture mechanisms observed between DN‐4PB Charpy and Izod impact tests is also made to show the effectiveness of DN‐4PB for investigation of impact fracture mechanisms of polymeric systems. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3070–3076, 2006     

Long fiber reinforcement of polypropylene/polystyrene blends

The recycling of inseparable polymer mixtures usually results in blends with poor mechanical properties. A mixture of PP and PS was taken as a model compound for a recyclate. The effect of adding glass fibers to a mixture of PP/PS (70/30) was studied, with special attention to long glass fiber reinforcement. Test specimens were made in three different ways: by dry blending (direct injection molding), mild compounding with a single screw extruder, and compounding with a twin screw extruder. The fiber concentration was varied from 0 to 30 wt%. The fiber lengths were determined to investigate fiber attrition. The fiber lengths in the samples were 1.09 mm for dry blending, 0.72 mm for single screw compounding, and 0.33 mm for twin screw compounding. The mechanical behavior was studied by unnotched and notched Izod impact and tensile tests. The PP/PS blend had a low fracture strain and low unnotched Izod impact strength compared with a PP homopolymer. With an increasing fiber concentration and fiber length, the modulus, tensile strength, and particularly the impact strength increased. With a 30 wt% glass fiber of the long fiber compound (dry blended), the modulus was raised by a factor of 3.5, the fracture stress by a factor of 2.5 and the unnotched Izod impact strength by a factor of 10. The product quality as judged by the scatter of the data was best for the twin screw compound and poorest for the dry blend. Compounding with a single screw extruder gave fairly constant injection molding product properties, combined with excellent mechanical properties.     

表面改性对聚丙烯/微米氢氧化镁复合材料性能的影响

研究了表面处理剂（钛酸酯和硅烷偶联剂）和原位聚合方法对聚丙烯/微米氢氧化镁（MH）复合材料的力学性能及流变性能的影响。采用DSC、SEM和毛细管流变仪对PP/MH（80/20）复合材料的性能进行了研究。结果表明：原位聚合改性后的微米MH与PP基体间的界面黏结力得到了加强,复合材料的冲击强度较填充未改性MH的复合材料提高了26.4 ％。在PP基体中添加聚合物包覆改性微米MH粒子的复合材料熔体流动速率较纯PP上升了64 ％。在相同剪切速率下,填充聚合物包覆改性MH的复合材料熔体表观黏度明显低于填充未改性微米MH的复合材料,表明聚合物包覆改性后的MH降低了其对PP熔体流动的阻碍作用,改善了PP/MH复合材料的流动性能。