聚丙烯/甘氨酸改性碳酸钙复合材料的研究

采用含有-NH2和-COO-双功能团的甘氨酸作为改性荆制备出甘氨酸复合球文石碳酸钙(CaCO3),并利用XRD及FTIR对其结构进行了表征.熔融共混制备了聚丙烯/甘氨酸改性碳酸钙(PP/CaCO3-Gly)和PP/CaCO3两种复合材料,并对其拉伸性能及流动性能进行了研究.结果表明,PP/CaCO3-Gly复合材料在流动性能、拉伸强度、弯曲强度等性能方面均高于PP/CaCO3复合材料.     

PP/HGMS复合材料真空热压成型及性能研究

以聚丙烯(PP)为基体,以高性能空心玻璃微珠(HGMS)为填充体,通过真空热压成型法制备聚丙烯/空心玻璃微珠复合材料。研究了HGMS填充体积分数对复合材料的密度、拉伸强度、压缩强度、剪切强度和吸水率的影响,分析了复合材料断口的微观形貌。结果表明,采用真空热压成型法能够制备性能优良的PP/HGMS复合材料。当HGMS体积分数达到50%时,复合材料的密度降低到0.645 g/cm~3,并且具有35.64 MPa的压缩强度和1.41%的吸水率。     

超微竹炭增强聚丙烯复合材料的制备与性能

为提高聚丙烯(PP)基复合材料的力学性能和热学性能,将不同质量分数的超微竹炭(UFBC)作为增强体引入聚丙烯,通过熔融挤出及注塑成型工艺制备UFBC/PP复合材料。利用SEM和DSC分析、力学强度和吸湿性测试等手段综合表征复合材料性能。结果表明:UFBC与PP基体间界面结合紧密;UFBC的添加对PP复合材料的力学强度有较好的增强效果:UFBC质量分数为30wt%时,UFBC/PP复合材料的拉伸强度和弯曲强度达到较大值,分别为26MPa和54MPa,较纯PP分别提高了9%和18%,UFBC/PP复合材料的耐湿性仍保持较佳水平,吸湿率均小于0.1%;UFBC质量分数为40wt%时,熔融温度提高了3.1℃;UFBC质量分数为50wt%时,UFBC/PP复合材料的结晶温度提高了10.8℃。UFBC的添加有效促进了UFBC/PP复合材料的结晶,改善了其加工性。     

聚丙烯/聚丙烯-石墨烯交替多层复合材料的结构及气体阻隔性能

利用多层共挤出技术制备了具有规整的交替层状结构的聚丙烯/聚丙烯-石墨烯(PP/PP-GR)交替多层复合材料,通过光学显微镜、扫描电子显微镜、气体渗透实验、力学性能测试研究了PP/PP-GR交替多层复合材料的结构与性能的关系。结果表明,分层叠加单元对复合材料施加的使熔体变宽变薄的"类双向拉伸"作用促进了石墨烯在PP中的分散、剥离和取向,从而使PP/PP-GR交替多层复合材料在低GR含量(体积分数0.082%)下同时具有高气体阻隔性(氧气渗透系数为1.01×10~(-15) cm~3·cm/(cm~2·s·Pa))和高断裂伸长率(1080.1%)。     

本征态聚苯胺/聚丙烯驻极体复合过滤材料的制备与性能

为研究本征态聚苯胺对非织造过滤材料的驻极性能和过滤性能的影响,制备具有良好性能的非织造复合材料。采用原位聚合法制备了本征态聚苯胺/聚丙烯(PANI/PP)复合材料,通过SEM扫描电镜对复合材料的表面形态进行了表征,测试分析及比较本征态聚苯胺/聚丙烯(PANI/PP)复合材料和PP材料电晕驻极后的表面静电势和电荷储存性能及过滤性能。实验结果表明,本征态聚苯胺/聚丙烯(PANI/PP)复合材料具有较好的驻极性能,本征态聚苯胺(PANI)能够大幅提升聚丙烯(PP)材料的表面静电势,同时在最佳驻极条件下本征态聚苯胺/聚丙烯(PANI/PP)复合材料比聚丙烯(PP)材料的电荷储存性能更加稳定,电荷保留率为60%左右,且过滤效率高出20%左右。     

原位固相接枝改性EPDM/PP/CaCO3复合材料相结构与性能的关系

以丙烯酸(AA)为纽带,将聚丙烯蜡(PPW)原位固相接枝在碳酸钙(CaCO3)表面,将得到的改性CaCO3与聚丙烯(PP)、三元乙丙橡胶(EPDM)通过2种不同的加工混合工艺制备了PP/EPDM/CaCO3三元复合材料。研究了改性CaCO3的表面性能,并通过热力学、动力学参数预测了复合材料中可能形成的分散形态,以阐明复合材料宏观性能与微观形态的关系。结果表明,改性CaCO3表面极性降低,与PP、EPDM的相容性变好,界面张力明显降低;从热力学因素考虑,改性CaCO3更容易分散在PP相中,和EPDM形成单独分散结构;动力学因素表明,将改性CaCO3先与EPDM复合再与PP复合的"两步法"工艺可以减缓CaCO3从EPDM中迁出而有利于形成以CaCO3为核、EPDM为壳的核-壳结构,这一结果通过电镜得到证实;核-壳结构使复合材料的各项力学性能均得到提高,尤其是在复合材料韧性方面,并且随着核-壳结构的增加,复合材料的韧性也随之增加,但这种核-壳结构不利于提高复合材料的熔体流动速率。     

纳米CaCO3改性聚丙烯性能与结构研究

本文利用双螺杆共混方法制备纳米CaCO3改性聚丙烯（PP），通过一步法、两步法两种共混工艺，研究了PP/纳米CaCO3复合材料的力学性能，采用TEM、XRD、DSC对分散情况、β-PP晶相的生成情况等进行了研究。结果表明，两步法制备PP/纳米CaCO3复合材料优于一步法；纳米CaCO3的加入，提高了PP的韧性，使PP成型收缩率增大。并对纳米CaCO3增韧PP和纳米CaCO3的加入使得PP收缩率增大的机理进行了探讨。     

汽车零部件包装用聚丙烯复合材料性能研究

目的研究纳米氧化铝(Al_2O_3)对聚丙烯(PP)/碱式硫酸镁晶须(MHSH)/氮-磷复配阻燃剂(N-P)复合材料力学性能和燃烧性能的影响。方法对MHSH和Al_2O_3进行表面改性处理,利用混合机将PP、MHSH、Al_2O_3和氮-磷复配阻燃剂进行混合,采用熔融共混法制备PP/MHSH/Al_2O_3/N-P复合材料。结果当Al_2O_3的添加质量分数为8%时,复合材料的力学性能较佳,随着Al_2O_3含量的继续增加,复合材料的力学性能逐渐降低;Al_2O_3质量分数为5%时,复合材料的极限氧指数(LOI)为23.6%,其阻燃性能明显得到提高,随着Al_2O_3填充量的继续增加,复合体系的LOI增长速度变缓;当Al_2O_3质量分数为8%时,复合材料力学和阻燃综合性能最佳。结论 Al_2O_3经表面改性处理后,其在PP基材中分散良好,对聚丙烯复合材料起到补强和增韧作用,复合材料的阻燃性能也得到了改善。     

电气石/PP复合材料的制备及性能研究

用钛酸酯对电气石进行改性,得到疏水性电气石粉体;将改性后的电气石粉体与聚丙烯(PP)按一定比例混合,在挤出机上挤出造粒,在注塑机上注塑成型制备出电气石/PP复合材料。力学性能测试表明:复合材料的拉伸性能、冲击性能都有一定程度的提高;当电气石含量为3%时(wt,质量分数),复合材料拉伸强度、冲击强度分别提高了15.38%和11.79%。电气石/PP复合材料同时具有释放负离子的功能,随着改性电气石含量的增加,复合材料负离子释放量不断增加。     

聚丙烯/聚烯烃弹性体/硅灰石复合材料的制备与热学力学性能

采用熔融共混的方法制备聚丙烯(PP)/聚烯烃弹性体(POE)/硅灰石(Wollastonite)复合材料,利用万能材料试验机、悬臂梁冲击机、差热扫描量热仪(DSC)和扫描电镜(SEM)研究了聚烯烃弹性体和硅灰石对聚丙烯的力学性能及热性能的影响。结果表明,POE弹性体对PP有很好的增韧作用,提高了PP的冲击强度,硅灰石在一定程度上有增强的作用,提高了PP/POE的拉伸强度;POE和硅灰石使复合材料的结晶温度有所提高,但使熔点有所降低。当POE占3%(质量分数,下同),硅灰石占3%时,复合材料的热学、力学性能最优,冲击强度比纯PP高出15.4%,拉伸强度高出2.6%,结晶温度高出5℃。     

微发泡聚丙烯/晶须复合材料的发泡行为与力学性能

将改性的MgSO4和CaCO3晶须加入聚丙烯中,在二次开模条件下制备微发泡聚丙烯(PP)/晶须复合材料,通过晶须在基体中的分散性、泡孔直径大小分布和泡孔密度,分析了不同晶须对材料的发泡行为与力学性能的影响.结果表明,晶须具有一定成核效应,CaCO3晶须的泡孔尺寸25.27μm左右,填充增强效果差;MgSO4晶须的泡孔尺...     

滑石粉/聚丙烯复合材料结晶度与相间形态对其力学性能的影响

用偶联剂改性的滑石粉（Talc）与聚丙烯（PP）共混制备Talc／PP复合材料,测试了复合材料的力学性能。用广角X射线衍射仪对聚丙烯的结晶状况进行了表征,计算了复合材料中聚丙烯的结晶度;用扫描电镜观察了样条的断口形貌,讨论了滑石粉填充量对材料结晶性能与相态结构的影响．以及PP相结晶度和体系的微相结构对复合材料的拉伸、弯曲及冲击性能的影响。实验结果表明,滑石粉的加入对复合材料的结晶行为、相态结构和力学性能有影响。在15％的滑石粉填充量时,聚丙烯相的结晶度达到最大值,材料的拉伸强度、弯曲强度也基本上达到最大值,而冲击强度却降到最低。扫描电镜照片显示,PP基体的结晶形态与复合材料的相态结构随滑石粉含量的改变而变化。     

新型的高杀菌纳米二氧化钛/聚丙烯复合材料的结构和物理特性研究

基于一种新型的纳米二氧化钛(TiO₂)粉体,利用熔体共混方式制备了纳米TiO₂/聚丙烯(PP)复合材料,研究了复合材料的相分散结构、结晶特性、力学性能、杀菌性能和流动性能。结果发现:新型纳米TiO₂在聚丙烯中有较好的分散度,绝大多数纳米TiO₂在聚丙烯中的聚集体尺寸接近于100纳米;新型纳米TiO₂对聚丙烯有一定的结晶成核作用,但并不能提高结晶度;复合材料的力学性能随纳米TiO₂含量的增加呈现出拉伸强度下降,伸长率降低,模量和冲击强度上升的趋势。2％纳米TiO₂含量的聚丙烯复合材料的综合物理机械性能较好。新型纳米TiO₂填充到PP中可以起到良好的抗菌杀菌作用,但也在一定程度上使聚丙烯发生氧化降解,进而导致纳米TiO₂/聚丙烯复合材料的流动性略优于纯聚丙烯。     

Effect of a novel coupling agent,alkyl ketene dimer,on the mechanical properties of wood–plastic composites

The objective of this study was to investigate the incorporation of poplar wood fibers both with and without a novel coupling agent, alkyl ketene dimer (AKD), on the mechanical properties of wood fiber/polypropylene (PP) composites. The resulting properties were compared to those obtained with the most commonly used coupling agent, maleic anhydride grafted PP (MAPP). Tensile and impact strengths of the composites decreased with increasing poplar wood fibers content. Tensile modulus of the composites increased by the incorporation of the wood fibers content up to 70 wt% but further increment in the wood fibers decreased the tensile modulus. At the constant content of poplar wood fibers (70 wt%), the tensile strength determined for the coupled composites with 5% AKD increased by 41% in comparison with the non-coupled composites while the tensile modulus increased by 45%, the impact strength of the coupled composites increased by 38%. The performance of 5% AKD on the mechanical properties of the composites is a little better than 3% MAPP. The good performance of 5% AKD is attributed to the enhanced compatibility between the poplar wood fibers and the polymer matrix. The increase in mechanical properties of the composites demonstrated that AKD is an effective coupling agent for wood fiber/PP composites.     

Improvement of impact property of natural fiber–polypropylene composite by using natural rubber and EPDM rubber

In this research, vetiver grass was used as a filler in polypropylene (PP) composite. Chemical treatment was done to modify fiber surface. Natural rubber (NR) and Ethylene Propylene Diene Monomer (EPDM) rubber at various contents were used as an impact modifier for the composites. The composites were prepared by using an injection molding. Rheological, morphological and mechanical properties of PP and PP composites with and without NR or EPDM were studied. Adding NR or EPDM to PP composites, a significant increase in the impact strength and elongation at break is observed in the PP composite with rubber content more than 20% by weight. However, the tensile strength and Young’s modulus of the PP composites decrease with increasing rubber contents. Nevertheless, the tensile strength and Young’s modulus of the composites with rubber contents up to 10% are still higher than those of PP. Moreover, comparisons between NR and EPDM rubber on the mechanical properties of the PP composites were elucidated. The PP composites with EPDM rubber show slightly higher tensile strength and impact strength than the PP composites with NR.     

长玻璃纤维/聚丙烯复合材料粒料注塑制品的拉伸强度

利用自行研制的玻璃纤维(GF)增强聚丙烯(PP)预浸装置,制备了长玻纤增强聚丙烯(LGFRP)粒料,并通过普通注塑机注塑成型。研究了界面改性、粒料长度、浸渍程度及退火处理等对注塑试样拉伸强度的影响。试验发现,用接枝马来酸酐PP作为界面相容剂,试样的拉伸强度明显提高。当接枝马来酸酐量占PP量的0.3 %左右时,试样强度达到最大值。长纤维粒料内纤维浸渍度越高,注塑试样的强度越好。15 mm和5 mm长纤维粒料注塑成型试样的拉伸强度均高于10 mm粒料注塑成型的试样。退火处理可较大程度地提高注塑试样的拉伸强度。     

Properties of Wood Fibre-Polypropylene Composites: Effect of Wood Fibre Source

This study examined the effect of type of wood fibre source on the physical and mechanical properties of wood fibre-polypropylene composites. Wood flour, fibres of heat-treated wood and pellets were used as sources of wood fibres in the manufacturing process. All studied wood fibre-polypropylene composites were made from 75% wood, 22% recycled polypropylene (PP) and 3% maleated polypropylene (MAPP). Wood fibre-polypropylene composites were compounded in a conical twin-screw extruder. Water absorption and thickness swelling were studied. Mechanical properties of the composites were characterised by tensile, flexural, and impact testing. Micromechanical deformation processes were investigated using scanning electron microscopy done on the fractured surfaces of broken samples. The durability of composites exposed to three accelerated cycles of water immersion, freezing and thawing was examined. The results showed that the density of the composites was a key factor governing water absorption and thickness swelling. A significant improvement in tensile strength, flexural strength, and Charpy impact strength was observed for composites reinforced with heat-treated fibre compared to composites reinforced with pellets and especially to wood flour reinforced composites. The flexural strength and dimensional stability performance reduced after exposure to freeze-thaw cycling for all composites, but the degree of these changes was dependent on the wood fibre source.     

PP-g-Si与KH550对聚丙烯/滑石粉体系的增容效果

硅烷接枝聚丙烯（ＰＰ－ｇ－Ｓｉ）对聚丙烯／滑石粉（ＰＰ／Ｔａ）混合体系有一定的增容作用,可使复合材料的力学性能得以提高,占复合材料总质量３．５％的ＰＰ－ｇ－Ｓｉ（相当于含硅烷０．２％）对ＰＰ／Ｔａ体系的增容效果与含０．８％（质量分数）的ＫＨ５５０的增容效果相当,ＫＨ５５０对复合材料中聚丙烯（ＰＰ）的结晶熔融行为基本上无影响。而ＰＰ－ｇ－Ｓｉ能进一步使材料中ＰＰ的结晶峰温和熔融峰温提高。     

Polybutene as a matrix for wood plastic composites

This study examined the feasibility of using polybutene-1 (PB-1), a ductile plastic, as a matrix for manufacturing wood plastic composites (WPCs) with improved toughness and ductility compared to currently commercialized WPCs. The processability, tensile, flexural, and impact properties of injection molded PB-1/wood-flour composite samples with varying proportions of wood flour were characterized. Analysis also included the morphology of fractured samples surface and adhesion between the polymer and wood flour using SEM. Comparisons of the mechanical properties and adhesion in the PB-1 composites to those of HDPE and PP-based WPCs found the composites made with PB-1 matrix significantly inferior in strength and stiffness (both in tensile and flexural) than their counterparts made of HDPE and PP matrices. In contrast, the processability, elongation at break, impact strength and adhesion in PB-1/wood-flour composites, superior to those of HDPE and PP, confirmed their suitability for use as a matrix in composites intended for applications subjected to high impacts.     

微纳米SiO2/PP复合材料增强增韧的实验研究

为了研究无机刚性颗粒对通用塑料聚丙烯 (PP) 的力学性能的影响, 采用熔融共混方法制备了经硅烷偶联剂A-151处理的SiO₂/PP 复合材料, 并通过其缺口冲击、 拉伸、 弯曲试验和冲击断面的形貌观察, 分析研究了微纳米SiO₂颗粒大小、 填充量、 表面改性以及不同颗粒大小SiO₂混合物对PP复合材料增韧、 增强效果的影响。实验结果表明: 纳米SiO₂的加入可以同时改善其韧性、 刚性和强度; 填充量相同, 颗粒越细, SiO₂/PP复合材料的力学性能越好。SiO₂经改性后填充到PP基体中, 明显改善了颗粒在基体中的分散性及基体与颗粒之间界面结合性能, 使复合材料的综合力学性能得到提高。不同颗粒大小的SiO₂混合后填充到PP基体中, 混合SiO₂的协同效应使复合材料拉伸、 弯曲性能进一步提高, 对PP基体具有更好的增强效果, 但其冲击性能下降。