马来酸酐接枝物和环氧树脂联合增容对PP/ABS复合材料性能的影响

在聚丙烯(PP)/丙烯腈-丁二烯-苯乙烯(ABS)共混物中添加复配的马来酸酐接枝物(PP-g-MAH和ABS-g-MAH)和复配固体环氧树脂(E-06/E-20/2E4MZ),研究了两种相容剂联合增容对共混物性能的影响。结果表明,马来酸酐接枝物添加量为5 phr时,对拉伸强度没有明显影响,而弯曲模量和冲击强度得到明显改善。在加入5phr马来酸酐接枝物的基础上,添加复配的固体环氧树脂,拉伸强度大幅提高,弯曲模量也进一步得到改善,冲击强度有所下降。马来酸酐接枝物和环氧树脂添加量均为5 phr时,增容效果最佳。DSC数据表明,复配马来酸酐接枝物和环氧树脂的联合增容提高了共混物的结晶度。SEM的分析结果表明,PP/ABS的质量比为70/30时,ABS相在共混物中的分布呈海-岛结构,加入5 phr固体环氧树脂后,分散相颗粒尺寸得到明显细化,分布均匀,界面脱黏现象得到显著改善。     

废旧聚丙烯编织袋回收料改性应用研究

废旧聚丙烯(PP)编织袋回收料分别与回收聚乙烯(PE)、回收橡胶粉、木粉共混,制备了增韧PP材料、热塑性弹性体和木塑复合材料,采用力学性能测试、SEM和DSC分析等手段对其性能和结构进行了表征。结果表明:随着回收聚乙烯(PE)含量的增加,回收PP/PE共混物的拉伸强度和冲击强度迅速提高;回收PP/橡胶粉共混物中加入聚丙烯接枝马来酸酐(PP-g-MAH)能起到增容的效果,随PP-g-MAH含量的增加,共混物的拉伸强度上升,永久变形减小;在回收PP/木粉复合材料中加入PP-g-MAH后,复合材料的冲击强度明显提高。     

相容剂对稻糠/聚丙烯复合材料加工性能和尺寸稳定性的影响

通过反应挤出法制备了马来酸酐接枝乙烯-辛烯共聚物(POE-g-MAH)相容剂,研究了POE-g-MAH对稻糠/聚丙烯(PP)复合材料力学性能、加工性能和尺寸稳定性的影响。结果表明:POE-g-MAH增容效果优于马来酸酐接枝三元乙丙橡胶(EPDM-g-MAH)和马来酸酐接枝聚丙烯(PP-g-MAH),能显著提高复合材料的拉伸强度、冲击强度、弯曲强度和尺寸稳定性;EPDM-g-MAH和PP-g-MAH对复合材料加工性能影响不大,而POE-g-MAH使稻糠/PP复合材料的最大转矩和平衡转矩明显降低,加工性能得到改善。     

马来酸酐接枝聚丙烯与成核剂提高聚丙烯/滑石粉复合材料性能的研究

分别考察了马来酸酐接枝聚丙烯(PP-g-MAH)、成核剂以及这两种不同改性机制的改性剂复配对聚丙烯/滑石粉(PP/Talc)复合材料力学性能和热性能的影响,结果表明:PP-g-MAH和α成核剂均能提高PP/Talc复合材料的强度、刚度和热变形温度,但随着改性剂含量的增大,这些性能都存在最大值或极限值;而且PP-g-MAH使复合材料的断裂伸长率明显降低,β成核剂可显著提高复合材料的冲击韧性和断裂伸长率,马来酸酐接枝聚丙烯与α成核剂复配对复合材料强度、刚度和热变形温度的改善具有协同性,且保持较高的断裂伸长率,马来酸酐接枝聚丙烯与β成核剂复配可获得更好的综合力学性能。     

PP-g-MAH对SEBS/PP/MH/EG阻燃复合体系结构与性能的影响

在氢氧化镁(MH)与可膨胀石墨(EG)复配阻燃石蜡油改性苯乙烯-乙烯/丁烯-苯乙烯(SEBS)/聚丙烯(PP)共混物(O-SEBS/PP)体系中,用马来酸酐接枝聚丙烯(PP-g-MAH)增容,研究其对O-SEBS/PP/MH/EG阻燃复合体系结构和性能的影响。结果表明:以一定量的PP-g-MAH代替基体中的PP增容后,复合材料在保持UL94垂直燃烧V-0级的同时,拉伸强度(σmax)与100%定伸强度(σ100)随着PP-g-MAH用量的增加而增大,在质量分数为6%时,分别为13.4 MPa和9.0 MPa,较未添加PP-g-MAH时分别提高13.6%和76.5%;撕裂强度则下降4.0%。复合材料的毛细管流变实验和淬断面扫描电子显微照片分析表明:PP-g-MAH的加入改善了复合材料中MH、EG与O-SEBS/PP共混物基体间的界面黏合力,提高了相容性。     

接枝物含量对高层建筑用GF/PP复合材料性能的影响

为了提高高层建筑用材料的力学性能,采用熔融共混的方法,在玻璃纤维(GF)增强聚丙烯(PP)复合材料中加入马来酸酐接枝PP(PP-g-MAH)与马来酸酐接枝聚烯烃(POE-g-MAH),分析接枝物含量对复合材料拉伸性能、弯曲性能以及冲击性能的影响。研究表明：当POE-g-MAH或PP-g-MAH的加入量为4 g时,复合材料的流动性明显改善,达到了最大熔体流动速率。当基体中接枝物含量上升后,复合材料的拉伸强度表现为先增大后减小的变化趋势,弯曲强度以及弯曲弹性模量都出现了先增大后减小的变化趋势,并在含有4 g接枝物时达到最大。当复合材料中接枝物含量增大后,含有POE-g-MAH接枝物的复合材料的冲击强度迅速增大。扫描电镜显示,加入接枝物后GF表面上存在明显附着物,GF和PP基体之间形成了良好相容性。     

玻璃纤维增强聚丙烯的力学性能研究

研究了玻璃纤维(GF)和马来酸酐接枝聚丙烯(PP-g-MAH)对聚丙烯力学性能的影响。结果表明:随着GF与PP的质量比增加,玻璃纤维增强聚丙烯的拉伸强度增加,冲击强度总体呈下降趋势。当PP与GF的质量比为55∶45时,拉伸强度最高,达到45MPa。当PP与GF的质量比一定时,在玻璃纤维增强聚丙烯复合材料中添加增容剂马来酸酐接枝聚丙烯(PP-g-MAH),可使其拉伸强度得到很大的提高,但是冲击性能却下降。当PP与GF的质量比为75∶25时,随PP-g-MAH与PP/GF复合材料的质量比增加,其拉伸强度先增大后减小,其冲击性能总体呈下降趋势。当PP-g-MAH,PP和GF的质量比为15∶75∶25时,其综合性能最优,拉伸强度为50.5MPa,冲击强度为4.3kJ/m2。     

相容剂对碳纤维增强聚丙烯复合材料性能的影响

研究了马来酸酐接枝聚丙烯(PP-g-MAH)和甲基丙烯酸缩水甘油酯接枝聚丙烯(PP-g-GMA)2种相容剂对碳纤维增强聚丙烯(CF/PP)复合材料性能的影响。结果表明:随着相容剂添加量的增加,CF/PP复合材料的拉伸强度、弯曲强度、缺口冲击强度增加,相容剂添加质量分数在6%时增加效果最为明显;2种相容剂对熔融温度及结晶度影响不大,但PP-g-MAH对CF/PP复合材料综合性能的提升优于PP-g-GMA。     

连续碳纤维增强聚丙烯性能研究

根据聚丙烯/碳纤维(PP/CF)复合材料的发展趋势,从聚丙烯的聚合方式、碳纤维含量、相容剂马来酸酐接枝聚丙烯(PP-g-MAH)含量以及聚烯烃弹性体(POE)含量4个方面对PP/CF复合材料冲击强度、弯曲模量、拉伸强度和弯曲强度进行研究。结果表明:PP-g-MAH的加入不仅可以增强PP/CF复合材料的韧性,同时还保持了PP/CF复合材料的刚性。     

熔融共混法制备PP/EVA/PP-g-MAH复合材料的性能研究

采用溶液接枝法首先制备出聚丙烯接枝马来酸酐(PP-g-MAH),分析了影响接枝率的因素,确定了最佳工艺参数。并采用熔融共混法制备PP/EVA/PP-g-MAH复合材料。相对于PP/EVA共混物,加入一定量的PP-g-MAH对于复合材料的拉伸性能和冲击性能都有不同程度的改善。PP-g-MAH加入改善了PP与EVA的相容性。     

XK型高速卷烟接嘴胶的制备

采用复合改性技术，对影响胶粘剂性的各种因素进行了选择和探讨，研制的ＸＫ型高速卷烟嘴胶具有初粘性高，干燥速度快，胶质细腻的特点，可以满足车速为６０００－８０００支／分钟高速机生产的要求。     

模式识别在复合材料研制中的应用

介绍了模式识别技术的概要及模式识别与复合材料探索的关系。以锆刚玉莫来石－氮化硼复合材料为例，给出了性能优良的参数优化区，找出了各影响因素之间的关系，并用实验进行了验证。     

植物纤维/聚酰胺复合材料研究进展

介绍了植物纤维聚酰胺复合材料的研究状况,着重讨论了材料复合方法和界面相容性等问题,并对未来工作进行了展望。     

全氟烷基丙烯酸酯对全氟丙烯酸酯乳液性能的影响

在十八烷基三甲基氯化铵(1831)和含氟乳化剂N,N-二甲基-N'-(2-三氟甲基-1-五氟乙基)(FS)的复合乳化作用下,以全氟烷基丙烯酸酯(FM)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)、甲基丙烯酸二甲基胺基乙酯(DM)为反应单体,以过硫酸钾(KPS)为引发剂,制备了全氟烷基聚丙烯酸酯乳液(FPE)。通过红外光谱(IR)、热失重分析(TG)对聚合物的结构和热稳定性进行了表征,并用接触角、原子力显微镜(AFM)分析了乳液的防水性能,表明FM成功地接枝到了聚合物上,随着含氟量的增加,分解温度达351.5℃;在含氟量达到w(FM)=12%时,水接触角达127°;采用Z粒度仪以及透射电镜(TEM)对共聚物外观形貌进行了表征,结果表明,乳胶粒的形态呈球形,呈单分散,平均乳液粒径为220 nm。     

新型高阻隔PVDC材料性能及应用

介绍了PVDC材料的分子结构、特性,综合评价不同种类PVDC薄膜的性能、特点,以及在实际包装上的应用,突出表现了PVDC材料优越的高阻隔性能。     

Lamellar BaTiO3 and its composites fabricated by the freeze casting technique

In this investigation, the freeze casting technique was employed to fabricate ceramic–epoxy composites. Porous BaTiO₃ ceramics exhibited lamellae architectures with strong anisotropy but with poor mechanical property. BaTiO₃–epoxy composites in longitudinal direction showed high dielectric constants which were 1 order of magnitude higher than those of conventional composites with randomly distributed ceramic particles. With the addition of alumina, the compressive strength of porous BaTiO₃ ceramics could be enhanced and the dielectric constants of ceramic–epoxy composites were lowered, but they were still much higher than those of the traditional composites. In a word, the properties of the composites could be optimized by adding proper amount of alumina.     

Dielectric,ferroelectric and magnetoelectric properties of in-situ synthesized CoFe2O4/BaTiO3 composite ceramics

Magnetoelectric composite materials have attracted more and more attention because of their coupling of ferroelectricity and ferromagnetism. It is a hotspot to realize the combination of ferromagnetic phase and ferroelectric phase. In this work, we used a new strategy to prepare CoFe₂O₄/BaTiO₃ composite ceramics: firstly, porous ferromagnetic CoFe₂O₄ phase was prepared by annealing of MOFs (metal organic frameworks) precursor Fe₃[Co(CN)₆]₂. And then, the ferroelectric BaTiO₃ phase in-situ grew in the pores of CoFe₂O₄ by a hydrothermal method. In the end, the CoFe₂O₄/BaTiO₃ composite ceramics sintered at different temperatures have been synthesized. The effects of sintering temperature on the structure, dielectric and ferroelectric properties have also been studied. Because the crystallinity and density increase with the increase of sintering temperature, the composite ceramic sintered at 1200 °C shows the best dielectric properties. It is found that sintering temperature has little effect on the ferroelectric and magnetic properties of ceramics. Taking the CoFe₂O₄/BaTiO₃ composite ceramic sintered at 1200 °C as an example, derived from the interaction between the ferromagnetic CoFe₂O₄ phase and ferroelectric BaTiO₃ phase, the applied magnetic field lead to the reduction of P_r and E_c.     

RDX/Al超细复合粒子的制备及性能研究

为了研究超细与复合途径对炸药性质的影响，运用YLG型高效研磨制备出RDX／Al超细复合粒子，并以水和乙醇作研磨介质进行了比较研究，并对复合粒子粒度，粒子形貌、热力学性能，粒子组分及爆热等进行了较全面的研究，结果表明，在水中研磨有助于粒子的复合，而在乙醇中研磨则有利于粒子的超细化和分散，在乙醇中研磨样品由于高能物质（C2H5O）3Al的生成，其爆热提高明显。为了解释这些现象，提出了超细复合模型及超细RDX／Al复合炸药热分散模型，其结论与实施结果相符合。     

Fracture behavior of carbon/epoxy laminated composite reinforced by iron powder

The fracture behaviors of a newly developed iron-powder reinforced carbon/epoxy laminated composite are investigated in this paper. Three kinds of DCB (double cantilever beam) specimens (without iron powder, with iron powder and with iron powder in a magnetic field) were prepared by the ASTM D 5528-94a. For the third DCB specimen, the unidirectional laminas were stacked with iron powder spread evenly on each lamina’s surface. This process was performed in a magnetic field to keep the iron powder standing along the out-plane direction. From the test data of Instron 5567, the fracture toughness, G _I , was calculated by using the compliance calibration method for each of the three kinds of specimens. The calculated fracture toughness shows that the iron powder effectively disturbs the progress of fiber branching between the laminates and provides a good stitching to the in-plane laminates during the fracture.     

Synthesis and photocatalytic performance of hollow sphere particles of SiO2-TiO2 composite of mesocellular foam walls

Hollow Microspheres of SiO₂-TiO₂ photocatalysts whose walls are made up of mesoporous cellular foams were synthesized with the aid of hexane as a swelling agent and P123 as a pore template by an emulsion templating method. Pore structure of materials and crystal phase of titanium oxide was tailored by hydrothermal and calcination temperature during synthesis of samples. The samples were characterized with field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), N₂ adsorption–desorption experiments, X-ray photoelectron spectroscopy (XPS) and X ray diffraction (XRD) techniques. The effect of pore structure and titania phase on photoactivity were evaluated by methylene blue (MB) degradation test under UV light as well. Results showed that hydrothermal temperature during synthesis process has a significant effect on pore and window sizes of mesostructured cellular foam. Interestingly, for the sample hydrothermally treated at higher temperature (130 °C), anatase to rutile transformation was avoided after calcination treatment as high as 800 °C. The highest photocatalytic activity was detected from the sample hydrothermally treated at 130 °C and calcined at 800 °C for which the highest degree of crystallinity and anatase phase as well as enhanced pore connectivity was obtained.