GB/HDPE复合材料拉伸性能及介电性能研究

采用小粒径玻璃微珠（GB）与HDPE熔融共混，研究了玻璃微珠用量及表面处理对复合材料拉伸性能及介电性能的影响。研究结果表明，无论玻璃微珠表面处理与否，GB／HDPE复合材料的拉伸强度和拉伸弹性模量均随着玻璃微珠用量的增加而增大；经过偶联剂KH550和EB151处理的玻璃微珠与HDPE复合后，拉伸强度和拉伸弹性模量有一定的提高。复合材料的介电常数随玻璃微珠用量增加呈现增大的趋势，经过改性的复合材料的介电常数比未经改性的有所增加，而玻璃微珠的添加和界面改性对介电损耗的影响不大。     

空心玻璃微珠增韧高密度聚乙烯的性能研究

采用玻璃微珠（GB）对高密度聚乙烯（HDPE）进行增韧改性。通过扫描电子显微镜、偏光显微镜和力学性能测试考察了偶联剂处理、基体韧性、玻璃微珠粒子用量、粒径大小和结晶等因素对HDPE/GB体系微观形态和性能的影响。结果表明,偶联剂可以明显改善空心玻璃微珠在基体中的分散,对于HDPE/GB体系,要求基体的最低冲击强度为5.0～5.5KJ/m2。玻璃微珠用量25%,粒径2.5μm时,冲击强度可达38.0kJ/m2。     

玻璃微珠/环氧树脂复合材料制备和性能研究

利用溶液共混法将不同尺寸玻璃微珠填料组合填充到环氧树脂基体中,通过固化工艺制备玻璃微珠改性环氧树脂复合材料,研究了玻璃微珠含量对复合材料力学性能、导热和介电特性的影响规律。结果表明：随着玻璃微珠填充含量的增加,复合材料的拉伸强度和弯曲强度明显提升;相比于纯的环氧树脂,玻璃微珠的填充显著增强了环氧树脂基体的力学性能。另外复合材料的平均热导率也随着玻璃微珠填充量的增加而增加;与过去报道的SiO₂单一尺寸填充的环氧树脂的热导率相比,本文中所使用的多种尺寸玻璃微珠混合填充的方法明显提升了环氧树脂基体的导热特性。随着填充含量的增加,介电常数和介电损耗同时增加,进一步揭示其介电增强效应主要归因于低频下的界面极化机制。     

GB/PP复合材料拉伸性能与介电性能的研究

采用小粒径玻璃微珠(OB)与聚丙烯(PP)熔融共混,研究了GB含量及表面处理对复合材料拉伸性能及介电性能的影响。研究结果表明,与未经表面改性的GB相比,经过偶联剂KH-550和EB-151处理的GB与PP复合后,其拉伸性能得到明显改善;且当GB含量为20%时,经过KH-550处理的GB/PP复合材料的拉伸强度、断裂伸长率和拉伸弹性模量比纯PP的分别提高了8.7%、109.6%和187.0%;复合材料的介电常数随GB含量的增加呈现增大的趋势,经过改性的复合材料的介电常数比未经改性的有所增加,而GB的含量和界面改性对介电损耗的影响不大。     

玻璃微珠改性PP和LLDPE力学性能的比较研究

采用玻璃微珠(GB)改性聚丙烯(PP)和线性低密度聚乙烯(LLDPE)，对玻璃微珠的用量、粒径和复合材料加工方法对材料的力学性能的影响进行了比较研究。结果表明：随着GB用量的增加，单、双螺杆挤出GB／PP复合材料的拉伸模量、弯曲强度和弯曲模量均呈线性增长的趋势，而屈服强度则有小幅下降；断裂应变在低含量时有所提高，然后迅速下降；单双螺杆挤出材料的冲击强度均有所提高，并在一定范围内随GB用量的提高而增大，且单螺杆挤出材料的冲击强度略高于双螺杆挤出材料。而GB／LLDPE中，随着GB用量的增加，单螺杆挤出复合材料的拉伸模量、弯曲模量均呈线性增长趋势，而屈服强度和弯曲强度在含量较高时略有上升；双螺杆挤出复合材料的拉伸模量、屈服应力、弯曲强度和弯曲模量均呈线性增长的趋势，两者的断裂应变都有所降低，但没有严重劣化LLDPE复合材料的冲击特性。GB的粒径对两种复合材料的力学性能影响不大，但对GB／PP复合材料的韧性有较大影响。单、双螺杆挤出GB／PP复合材料的冲击强度在一定范围内较纯料有一定提高；同样的，双螺杆挤出复合材料的冲击强度低于单螺杆挤出材料。     

镀银玻璃微珠/硅橡胶导电复合材料导电性能的影响因素

研究镀银玻璃微珠的用量、粒径、表面改性工艺以及导电硅橡胶硫化程度等对镀银玻璃微珠/硅橡胶复合材料导电性能的影响.结果表明,镀银玻璃微珠的粒径越大,复合材料的导电性能越好;湿法预处理和原位改性-分散工艺制得复合材料的导电性能和导电稳定性优于直接干混工艺;导电硅橡胶硫化程度的提高有利于提高材料的导电性能;Payne效应的大小与导电硅橡胶的体积电阻率有很强的相关性.     

玻璃微珠改性聚氯乙烯复合材料的性能研究

选用含氨基较多的硅烷偶联剂(KH792)和聚醚型成膜剂复合处理玻璃微珠,制备了聚氯乙烯/玻璃微珠(PVC/GB)复合材料。研究了玻璃微珠用量对复合材料力学性能、热性能和流动性能等的影响。结果表明:当玻璃微珠加入量在0%~15%时,玻璃微珠在聚氯乙烯基体中均匀分散、不团聚,随着玻璃微珠加入量的增加,其复合材料的韧性、耐热性逐渐提高,同时赋予材料良好的熔体流动性。     

空心玻璃微珠对碳纤维增强聚丙烯性能的影响研究

以碳纤维(CF)增强聚丙烯(PP)作为基础材料,添加空心玻璃微珠(GB)对其进行共混改性,研究GB的加入量对其流动性能和力学性能的影响。转矩流变性能、拉伸性能、冲击性能和微观形貌的分析与研究结果表明,GB对PP/CF复合材料具有增强增韧的作用。     

空心玻璃微珠改性环氧树脂的制备及其性能研究

以双酚F环氧树脂为基体,以空心玻璃微珠为填料,制备环氧树脂绝缘复合材料。用硅烷偶联剂KH-570对空心玻璃微珠进行表面改性,并研究改性后的空心玻璃微珠对复合材料力学性能、热机械性能以及电绝缘性能的影响。实验结果表明:随着填料含量的增加,力学性能表现出先增加再降低的趋势,并在空心玻璃微珠含量为4%时,性能达到最优;热机械性能和介电性能均随填料含量的增加而呈现降低的趋势,并在空心玻璃微珠含量为8%时,介电常数最低。     

超细空心微珠填充聚氯乙烯复合材料的研究

选用三种不同粒径(2μm、3．8μm和11μm)的空心微珠制备了聚氯乙烯／空心微珠(PVC／GB)复合材料。研究了GB的粒径、表面处理剂及其用量对复合材料力学性能、介电性能和阻燃性等的影响，并与PVC／超细CaCO3复合材料的性能进行了对比。结果表明，经硅烷偶联剂处理的GB与PVC基体之间存在良好的界面粘附作用；在体积分数0～11％范围内，粒径为3．8μm的GB能同时提高PVC复合材料的力学性能、介电性能和阻燃性能，且GB改性效果明显优于超细CaCO3填充体系。该复合材料能作为轻质、高强度和阻燃的电缆护套材料使用。     

Mechanical properties and morphologies of polypropylene with different sizes of glass bead particles

A commercial grade of isotactic polypropylene (PP) was used to study the mechanical properties and morphologies of the PP composites filled with four sizes of glass bead particles. The glass bead particles used were with average particle sizes of 15 μm (GB15), 10 μm (GB10), 5 μm (GB5), and 2.5 μm (GB2.5), respectively. It was clear that the glass bead size was an important factor on the determination of mechanical properties of the composites. As a whole, in view of the scatter in the data, under the condition of same filler content, the yield strength and impact strength of the composites filled with smaller glass bead particles was higher than those of the composites filled with bigger ones. And the flexural strength and modulus of the composites filled with GB10, GB5, or GB2.5 particles could be regarded as the same. The flexural strength and modulus of the composites filled with GB15 particles were higher than those of the composites filled with other three sizes of particles. Among four sizes of glass bead particles, GB2.5 had the best toughening effect to improve the impact strength of PP matrix. And the major toughening mechanism of the PP/GB2.5 composites was the pinning effect introduced by GB2.5. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers     

PE-LLD/玻璃微珠复合材料的熔融与非等温结晶行为研究

采用X射线衍射法、偏光显微镜和差示扫描量热法考察了玻璃微珠(GB)对线形低密度聚乙烯(PE-LLD)的结晶形态以及非等温结晶与熔融行为的影响。通过Jeziorny法和莫志深法研究了复合材料的非等温结晶动力学,并利用Kissinger方程计算了PE-LLD/GB复合材料的非等温结晶活化能。结果表明,GB的加入细化了PE-LLD的晶粒,降低了晶粒尺寸和晶体完善程度;当GB含量为5 %（质量分数,下同）时,复合材料的结晶结构完善程度的分散性最大;GB起到了异相成核作用,提高了PE-LLD的结晶起始温度,当GB含量为8 %时,复合材料的结晶速率达到最大值;当GB含量低于5 %时,复合材料结晶活化能高于纯PE-LLD。     

高性能滚塑专用料的研究

研制了尼龙6(PA6)、小粒径空心玻璃微珠(GB)复合改性PE-LLD高性能滚塑专用料,研究了PA6和GB对复合材料力学性能和热性能的影响.结果表明,适当含量的PA6有利于提高复合材料的力学性能和热性能;适当含量的经偶联剂处理的GB不仅可以提高复合材料的刚性和耐热性能,而且可以保持材料的流动性,同时不致于使材料密度大量...     

Impact fracture behavior of PP/EPDM/glass bead ternary composites

The effects of glass bead filler content and surface treatment of the glass with a silane coupling agent on the room temperature impact fracture behavior of polypropylene (PP)/ethylene‐propylene‐diene monomer copolymer (EPDM)/glass bead(GB) ternary composites were determined. The volume fraction of EPDM was kept constant at 10%. The impact fracture energy and impact strength of the composites increased with increasing volume fraction of glass beads (?_g). Surface pretreatment of the glass beads had an insignificant effect on the impact behavior. For a fixed filler content, the best impact strength was achieved when untreated glass beads and a maleic anhydride modified EPDM were used. The impact strength exhibited a maximum value at ?_g=15%. Morphology/impact property relationships and an explanation of the toughening mechanisms were developed by comparing the impact properties with scanning electron micrographs of fracture surfaces.     

Competing effect between filled glass bead and induced β crystal on the tensile properties of polypropylene/glass bead blends

The blends of the polypropylene (PP‐1) with various glass bead contents were prepared via melt blending. Differential scanning calorimetry (DSC) and wide‐angle X‐ray diffraction (WAXD) results indicated that the β crystal existed in PP‐1 and increased with increasing glass bead content up to 6 wt %. It was generally known that the stiffness of a polymer increased with introducing rigid particles, and the stiffness of the β crystal was less than that of the α crystal. This competing effect thus leads to the tensile modulus of PP‐1/glass bead blend decreasing with increasing glass bead content up to 6 wt %; thereafter, it increased with increasing glass bead content. For the purpose of comparison, the polypropylene (PP‐2) without the β crystal was employed to blend with glass bead. The tensile tests showed that the modulus of the PP‐2/glass bead blend increased continuously with increasing glass bead content. This result further supported that the tensile modulus behavior of PP‐1/glass bead blends resulted from the competing between the filled glass bead and the induced β crystal. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1729–1733, 2005     

聚丙烯／玻璃微珠复合材料性能研究

采用熔融挤出成型方法制备了聚丙烯（PP）／玻璃微珠（GB）复合材料,研究了GB含量及粒径对复合材料的性能与收缩率的影响。结果表明,随GB含量的增加,复合材料的弯曲模量及热变形温度增加,但拉伸强度及收缩率下降,而流动性与冲击强度先增大后减少。同时也发现,相比大粒径而言,小粒径GB对改善复合材料的性能更为有效,而且大小粒径GB复配体系收缩率要小于各自体系的收缩率。     

玻璃微珠填充聚丙烯复合材料的力学性能研究

用硅烷偶联剂对玻璃微珠(GB)进行表面改性,采用熔融共混法制备了GB填充聚丙烯(PP)复合材料,考察了PP/GB复合材料的力学性能。结果表明:随着GB用量的增加,复合材料的断裂伸长率降低;拉伸弹性模量呈非线性形式增加;拉伸强度开始下降速率较快,然后趋于平缓;复合材料的冲击强度先随GB用量的增加而增加然,后降低;偶联剂处理GB有利于复合材料力学性能的改善。     

Nonisothermal crystallization behavior of glass‐bead‐filled polypropylene

The effects of the glass‐bead content and size on the nonisothermal crystallization behavior of polypropylene (PP)/glass‐bead blends were studied with differential scanning calorimetry. The degree of crystallinity decreased with the addition of glass bead, and the crystallization temperature of the blends was marginally higher than that of pure PP at various cooling rates. Furthermore, the half‐time for crystallization decreased with an increase in the glass‐bead content or particle size, implying the nucleating role of the glass beads. The nonisothermal crystallization data were analyzed with the methods of Avrami, Ozawa, and Mo. The validity of various kinetic models for the nonisothermal crystallization process of PP/glass‐bead blends was examined. The approach developed by Mo successfully described the nonisothermal crystallization behavior of PP and PP/glass‐bead blends. Finally, the activation energy for the nonisothermal crystallization of pure PP and PP/glass‐bead blends based on the Kissinger method was evaluated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2026–2033, 2006