热固性树脂/纳米SiO2复合材料性能影响因素的分析

热固性树脂/纳米SiO2复合材料在添加纳米SiO2微粒后具有明显的成核效应。复合材料可显示低诱导期、高结晶速率和较小的半结晶时间等特点。同时纳米SiO2微粒的加入可提高储能模量(Es)、玻璃化转变温度(Tg),且二者的变化都与纳米SiO2微粒的质量分数成正比关系。这表明纳米SiO2微粒与热固性树脂之间存在较强的界面作用。对热固性树脂/纳米SiO2复合材料性能影响因素进行了分析。     

纳米微粒改性聚甲基丙烯酸甲酯的研究进展

综述了近年来纳米金属氧化物、非金属氧化物、有机化合物等纳米微粒改性聚甲基丙烯酸甲酯(PMMA)的研究。纳米微粒的添加可以提高其抗紫外线、阻燃、抗静电等性能。展望了纳米微粒改性聚甲基丙烯酸甲酯复合材料的发展前景。     

四针状纳米ZnO/丙烯酸树脂复合多功能涂料

以丙烯酸树脂为基体,通过纳米微粒直接分散法,制备了四针状纳米ZnO/丙烯酸树脂复合材料。当硅烷偶联剂的用量为纳米ZnO的10%(质量分数)时,可获得ZnO微粒分散性好的复合材料,对该材料进行的红外吸收测定表明,复合体系的透射率随着纳米ZnO的加入急剧下降,具有良好的红外屏蔽性能,同时该涂料也表现出良好的抗菌及抗静电性能。     

纳米ZnO/PP及ZnO/CaCO_3/PP复合材料的性能研究

纳米氧化锌(ZnO)与聚丙烯(PP)通过熔融共挤制得了ZnO/PP纳米复合材料.研究了ZnO/PP纳米复合材料的力学、流变学性能与纳米ZnO添加量之间的关系;同时制备了ZnO/CaCO3/PP三元纳米复合材料并对其进行了机械性能和制备成本分析.结果表明,ZnO/PP纳米复合材料的熔体质量流动速率较纯PP有较大程度的提高;纳米CaCO3的加入不但可以降低生产成本,而且可以显著改善体系的冲击韧性;材料的拉伸破坏属于韧性断裂过程.     

镍基氧化铝纳米微粒复合电镀的研究现状

以Al2O3纳米微粒为复合材料的复合电镀是一种取代镀硬铬的极有价值的复合表面技术。Al2O3微粒与镍金属共沉积可明显提高镀层的硬度、耐磨性与耐蚀性。主要阐述了Al2O3纳米微粒与金属镍共沉积的工艺条件对沉积速率和镀层性能的影响。并且指出Al2O3纳米微粒复合镀镍中关键问题是如何提高复合镀层中纳米微粒的含量及镀层形貌对镀层性能的影响,以寻找控制镀层表面形貌的条件。     

磁性坡缕石复合材料的制备及性能

以提纯和超细制备的纳米坡缕石矿浆与纳米Fe3O4磁性流体复合,经加热和活化处理后,制备了外包磁性微粒的磁性坡缕石纳米复合材料.当每100 g坡缕石中加入24 g纳米磁性微粒时,磁场对磁性坡缕石纳米复合材料的截留量为90.2%,其磁化率为4.3×10-2.利用化学分析、X射线衍射、红外光谱、透射电镜及磁性能测试等分析手段对磁性坡缕石复合材料进行了表征及磁性能测试,结果表明:所制备的坡缕石磁性复合材料具有高分子靶向药物载体材料的功能,有望成为新型靶向药物载体材料.     

纳米ZnO/PP及ZnO/CaCO_3/PP复合材料的性能研究

用纳米氧化锌(ZnO)与聚丙烯(PP)通过熔融共挤制得了ZnO/PP纳米复合材料,研究了ZnO/PP纳米复合材料的力学、流变学性能与纳米ZnO添加量之间的关系;同时制备了ZnO/CaCO3/PP三元纳米复合材料并对其进行了机械性能和制备成本分析。结果表明:ZnO/PP纳米复合材料的力学性能随纳米ZnO添加量的增加表现出冲击韧性先升后降,拉伸强度变化不敏感的特点;纳米CaCO3的加入不但可以降低生产成本,而且可以显著改善体系的冲击韧性;材料的拉伸破坏属于韧性断裂过程。     

纳米ZnO/PP及ZnO/CaCO3/PP复合材料的性能研究

用纳米氧化锌（ZnO）与聚丙烯（PP）通过熔融共挤制得了ZnO／PP纳米复合材料．研究了ZnO／PP纳米复合材料的力学、流变学性能与纳米ZnO添加量之间的关系;同时制备了ZnO／CaCO3／PP三元纳米复合材料并对其进行了机械性能和制备成本分析。结果表明：ZnO／PP纳米复合材料的力学性能随纳米ZnO添加量的增加表现出冲击韧性先升后降,拉伸强度变化不敏感的特点;纳米CaCO3的加入不但可以降低生产成本,而且可以显著改善体系的冲击韧性;材料的拉伸破坏属于韧性断裂过程。     

纳米SiO_2/NR复合材料老化性能的研究

本文研究了纳米SiO2/NR复合材料制备方法。硅烷偶联剂Si69用量和纳米SiO2用量对纳米SiO2NR复合材料力学性能和老化性能的影响。结果表明,乳液共凝法制备的纳米SiO2NR复合材料力学性能和耐老化性能优于机械共混法制备的纳米SiO2NR复合材料力学性能和耐老化性能。加入Si69后,纳米SiO2NR复合材料力学性能和耐老化性能得到改善。在天然橡胶中加入纳米SiO2,改善了天然橡胶的力学性能和耐老化性能。     

聚合物纳米复合材料的制备方法

从纳米微粒的分散方法以及纳米复合材料的成型技术两方面综述了国内外纳米复合材料的制备方法的发展状况,总结了纳米微粒填充法与紫外光辐射固化技术的结合在制备纳米复合材料方面的几种优点,认为该方法是未来聚合物无机纳米复合材料的主要、新型制备方法。     

Improved melting strength of polypropylene by reactive compounding with ultrafine full‐vulcanized polybutadiene rubber (UFBR) particles

Ultrafine full‐vulcanized polybutadiene rubber (UFBR) in particle sizes of ca. 50–100 nm has been used for modifying mechanical and processing performances of polypropylene (PP), and PP‐g‐maleic anhydride (PP‐MA) has been used as a compatibilizer for enhancing the interfacial adhesion between the two components. The results show that PP/UFBR possesses rheological behaviors such as highly branched PP when UFBR content in blends reaches 10 wt%, while in contrast, the much low content of UFBR combining small amount of PP‐MA endows the material with rheological characteristics of high melt strength materials like highly branched PP. The mechanism accounting for the rheological behaviors of binary blends and effectiveness of PP‐MA on PP/UFBR blends has been proposed. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

PP/Mg(OH)_2阻燃复合材料流变行为的研究

用日本岛津ＡＧ－２０００型毛细管流变仪，在几个温度下，研究了ＰＰ和ＰＰ／Ｍｇ（ＯＨ）２阻燃复合材料的流变行为。研究结果表明：ＰＰ／Ｍｇ（ＯＨ）２阻燃复合材料熔体流变行为同ＰＰ一样，仍属于非牛顿型假塑性行为；在２００℃温度，相同剪切速率下，ＰＰ和ＰＰ／Ｍｇ（ＯＨ）２阻燃复合材料的粘流活化能十分接近，１０３Ｓ－１剪切速率下，ＰＰ／Ｍｇ（ＯＨ）２阻燃复合材料熔体粘流活化能为３．７１４Ｋｃａｌ／ｍｏｌ，与ＰＰ相差只有０．０３７Ｋｋｃａ／ｍｏｌ，挤出胀大比为１．２９，低于ＰＰ。     

混杂碳质填料对聚丙烯流变性能的影响

为研究多种碳质填料混杂对聚丙烯(PP)流变性能的影响,采用熔融共混法制备了聚丙烯(PP)/石墨烯(GNP)/碳纳米管(CNT)/炭黑(CB)复合材料,采用旋转流变仪研究了复合材料的流变行为。结果表明,加入的碳质填料,显著提高了复合材料的储能模量(G')、损耗模量(G″)以及复数黏度(η*)。在相同含量下,PP/CNT复合材料流变逾渗值最小,其次是PP/CB,最后是PP/GNP。当CNT含量超过0.5%时,PP/GNP/CNT复合材料出现了模量平台;当CB含量超过3%时,PP/GNP/CB复合材料出现模量平台;CNT与CB的协同作用最佳,CNT和CB的加入有利于GNP的分散;GNP与少量的CNT和CB共混能使G'、G″以及η*得到明显提高,同时,能够大幅减小流变逾渗值;纯PP以及PP/GNP复合材料的损耗因子随频率的增加而下降,PP/CNT、PP/CB、PP/GNP/CNT/CB复合材料损耗因子随频率增加呈先升高后下降的趋势。     

PP/滑石粉/PP-g-MAZn三元复合体系流变性能的研究

采用双料筒毛细管流变仪系统地研究了以聚丙烯接枝马来酸锌(PP-g-MAZn)为界面改性剂的PP/滑石粉/PP-g-MAZn三元复合体系的流变性能。结果表明:随着剪切速率的增加,PP/滑石粉/PP-g-MAZn三元复合体系表观黏度下降;同一剪切速率下,与PP/滑石粉二元复合体系相比,PP/滑石粉/PP-g-MAZn三元复合体系的表观黏度和剪切应力变小;随着PP-g-MAZn用量的增加,三元复合体系表观黏度变化不大,体系的黏流活化能随着剪切速率的增大而降低。挤出物弹性效应的研究表明:PP/滑石粉/PP-g-MAZn三元复合体系挤出物无熔体破裂现象表,面基本光滑对,剪切速率敏感性下降。     

Structure and properties of peroxide dynamically vulcanized polypropylene/ethylene–propylene–diene/zinc dimethacrylate composites

Peroxide dynamically vulcanized thermoplastic olefin (TPO) based on polypropylene (PP)/ethylene–propylene–diene (EPDM) loaded with zinc dimethacrylate (ZDMA) was prepared. The addition of ZDMA improved the complex viscosity of the resulting materials in the melt state significantly, as determined from oscillatory rheology analyses. Dynamic mechanical analysis (DMA) and transmission electron microscopy (TEM) examinations were performed to evaluate the structure of the PP/EPDM/ZDMA composite. Atomic force microscope (AFM) and scanning electron microscopy (SEM) were used to study the morphology. The degree of crystallinity was evaluated using X‐ray diffraction method (XRD). The results revealed that incorporation of ZDMA resulted in a size reduction of the rubber droplets and improved the compatibility between rubber and PP phases. The nanoparticles of the polymerized ZDMA (PZDMA) served as an effective nucleating agent for the crystallization of PP. The rheological properties and mechanical properties were improved by ZDMA. Particularly, the izod impact strength of the PP/EPDM/ZDMA (80/20/6, w/w) composite is nearly 2 times higher than the PP/EPDM (80/20, w/w) and 12 times higher than the PP; besides, the elongation at break of the PP/EPDM/ZDMA (80/20/6, w/w) is 3 times higher than that of the PP/EPDM (80/20, w/w) and 6 times higher than the PP. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

Polypropylene–intumescent flame‐retardant composites based on meleated polypropylene as a coupling agent

The phosphoric acid‐pentaerythritol‐melamine copolymer, which is composed of three main components of intumescent flame retardant (IFR) and has optimal intumescent degree, was selected as IFR. The influence of meleated polypropylene (PP‐g‐MAH) on the properties and compatibility of IFR polypropylene (PP) composites were studied. The results obtained from mechanical tests, rheological behavior of composites, and scanning electron microscope showed that PP‐g‐MAH was a true coupling agent for IFR/PP blends and did not change the necessary flame retardancy. The cocrystallization between bulk PP and PP segments of PP‐g‐MAH was also proven by WAXD analysis. Flow test showed that the flow behaviors of composites in the melt are those of a pseudoplastic and it is very small for PP‐g‐MAH affecting rheological behavior of the PP/IFR composite. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 257–262, 2002     

聚丙烯/蒙脱土纳米复合材料的流变性能研究

制备了MMT/MgCl2/TiCl4插层催化剂,并通过原位聚合的方法制得聚丙烯/蒙脱土纳米复合材料。测试了聚丙烯/蒙脱土复合材料在不同温度及不同蒙脱土含量下的流变性能。结果表明:不同蒙脱土含量的聚丙烯复合材料,其表观黏度随剪切速率的增大而减小,剪切应力随剪切速率的增大而增大。符合流体切变稀释的性质,该性质有利于复合材料的成型加工。     

The influence and mechanism of elastomer types on electrical and mechanical properties of polypropylene insulation materials for high voltage cables

Polypropylene (PP) becomes a superior candidate material for new environmentally friendly cable main insulation with its excellent heat resistance, electrical properties, and degradability. However, in practical application, PP material is aging and vulnerable and its toughness is poor. The mechanical properties of PP material can be improved by elastomer modification, but the effects of different elastomers on the comprehensive properties of composite specimens are quite different. In this paper, the electrical and mechanical properties of different types of elastomer-modified PP composites are compared and analyzed by combining experimental and molecular simulation (MS) methods. The experimental results show that the SEBS/PP composite material has the lowest trap energy levels among all kinds of composite materials, its space charge accumulation is 1.96 × 10⁻⁹C, and the mechanical and rheological properties improvement of the composite is the most remarkable. Meanwhile, the volume resistivity is reduced by two orders of magnitude compared with pure PP. However, the breakdown strength of all kinds of composite materials decreases by different degrees after the modification. The solubility parameters (δ) and the free volume are further investigated by the molecular simulation, which shows that the δ of SEBS is similar to that of PP, which represents the best compatibility. Moreover, the SEBS/PP composite material has the strongest inter-molecular force and the most excellent toughness improvement for PP. This work provides a theoretical basis for elastomer selection in PP modification.     

纳米铜粉/PP复合材料的流变性能及动态力学性能研究

将纳米铜粉经硅烷偶联剂KH550处理后,按不同的配比与聚丙烯(PP)混合,经螺杆挤压制得纳米铜粉/PP复合材料,研究了纳米铜粉在PP复合材料中的分散性以及PP复合材料的流变性能和动态力学性能。结果表明:经改性后的纳米铜粉均匀分散在PP中;纳米铜粉/PP复合材料为非牛顿假塑性流体;在低剪切速率下,复合材料熔体的黏度高于纯PP的,随着纳米铜粉的含量增加,复合材料体系的表观黏度增大,高剪切速率时,纳米铜粉的添加量对复合材料的流动性能影响较小;当复合材料体系中纳米铜粉的质量分数小于或等于0.5%时,其熔体流动性能提高,储能模量小于纯PP的,当纳米铜粉质量分数大于0.5%时,其储能模量提高并高于纯PP的。     

聚丙烯/聚乳酸共混体系的结构和性能

以聚丙烯(PP)树脂与降解材料聚乳酸(PLA)的共混体系为主要研究对象,探索PLA用量对PP结构、力学性能和流动性的影响。SEM结构分析表明:适量的PLA,会使PP表现出明显的韧性断裂现象。力学性能和流动性研究结果表明:PLA含量对PP的力学性能有较大影响。当PLA含量为10份时,PP/PLA共混体系的冲击强度是PP的1.3倍,但PP的拉伸强度和弹性模量有所下降。剪切速率一定时,PP/PLA共混体系的表观粘度随测试温度的提高而降低。