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用双螺杆挤出机对聚丙烯(PP)进行硅烷交联改性,制备出了高熔体强度的PP;以偶氮二甲酰胺为发泡剂,用压制成型的方法制备了泡孔均匀、细密的PP泡沫板材,研究了PP发泡板材的冲击强度、弯曲强度和制品的密度。
结果表明,发泡剂用量、发泡调节剂用量、压制工艺条件对PP发泡板材的性能有很大影响,当发泡剂的含量为2.5份(质量份,下同),压制成型温度为195 ℃、压力为20 MPa、发泡时间为17 min, 发泡调节剂用量为8份时,PP发泡板材的密度最低、力学性能最优、泡孔结构最细密均匀。 相似文献
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利用纳米CaCO3对聚丙烯(PP)的增强增韧作用,采用合理的成型工艺及设备,挤出成型了性能优越的发泡板材。详细研究了CaCO3粒子对板材力学性能的影响,研究表明:纳米CaCO3粒子的含量接近4%时(相对PP),粒子在基体中的分散良好,复合材料的拉伸强度和冲击强度达到最大值;纳米粒子是否经过表面处理,只对材料冲击强度的影响产生不同效果;微米CaCO3粒子含量小于5%时(相对PP),对板材的性能影响很小,但超过该含量后,板材的性能明显下降。 相似文献
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聚丙烯(PP)微孔发泡材料具有质轻、力学性能较高的特点,PP基体性质、发泡剂种类、发泡制备成型工艺、化学改性方法、共混及填充改性等方法均可以影响发泡材料的泡孔结构及发泡材料的性能。综述了PP微孔发泡材料的制备成型工艺、化学、共混、纳米、填充等改性方法研究进展,指出采用成本低廉、无毒的化学类发泡剂制备泡孔结构良好的PP微孔发泡材料将是今后研究的热点。PP的交联及接枝改性技术,与其它聚合物、填料共混技术是改善泡孔结构、提高泡沫材料发泡性能和力学性能的途径,研究改性材料与PP基体材料的界面相容性问题也是今后的研究方向。 相似文献
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聚丙烯发泡材料的研究进展 总被引:1,自引:0,他引:1
简要阐述了聚丙烯发泡材料的性能,分别从直接使用高熔体强度PP、化学交联/接枝改性、共混/填充改性这三种提高PP发泡性能的途径上对目前聚丙烯发泡材料的研究进展进行了介绍。 相似文献
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在工程实践中,作为装配式建筑的墙体材料,既要有较好的保温隔热性能,又要满足一定的力学性能。轻质泡沫混凝土是一种很好的选择,但普通的泡沫混凝土材料在满足热工性能时其力学性能往往表现较差。本文提出一种高强度低导热泡沫混凝土制备方法,研究了水胶比、泡沫掺量、粉煤灰掺量和聚丙烯(PP)纤维掺量对泡沫混凝土的抗压强度和导热系数的影响,并采用扫描电镜(SEM)探究了粉煤灰和PP纤维对泡沫混凝土微观形貌的影响。结果表明:当水胶比为0.6、泡沫掺量为4%(质量分数,下同)、粉煤灰掺量为25%以及PP纤维掺量为0.2%时,泡沫混凝土的抗压强度较高且导热系数较低。 相似文献
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简述了塑术复合发泡材料的优缺点,归纳了聚丙烯、木粉、添加剂、工艺参数因素等对木粉填充聚丙烯复合发泡的影响,任此基础上对木粉/聚丙烯复合发泡材料的前景进行了展望。 相似文献
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Effect of compatibilizers on water absorption kinetics of polypropylene/wood flour foamed composites
Polypropylene (PP)/wood flour foamed composites were prepared by taking PP:wood flour in the ratios of 100 : 0, 90 : 10, 80 : 20, 70 : 30, and 60 : 40 (w/w), with and without compatibilizers like maleic anhydride‐treated wood flour and maleic anhydride‐grafted PP (PPgMA). The foamed composite samples were employed for water swelling at 27°C, 70°C, and in steam. The absorption of water increased with increase in filler contents for all three‐temperature conditions. The maleic anhydride‐treated wood flour and PPgMA showed reduction in water swelling, and the best one was in case of the PPgMA‐foamed composites for respective conditions. Diffusion, sorption, and permeation coefficients were determined to study the absorption kinetics. FTIR spectra were also recorded for 30 wt % of filler loading for all the composites, which showed the effect of compatibilizers on reduction in water absorption in foamed PP/wood flour composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2530–2537, 2006 相似文献
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在过氧化二异丙苯(DCP)引发下,研究三烯丙基异氰脲酸酯(TAIC)对聚丙烯(PP)的交联程度、熔体强度及其发泡性能的影响。在TAIC加入前后,分别测定PP的抗流淌能力和熔体流动速率及PP发泡材料的凝胶率和力学性能。结果表明,DCP/TAIC交联体系使PP的抗流淌时间平均延长了6-7min;当DCP为1.4份时,PP发泡材料的最大凝胶率提高14%,拉伸强度和撕裂强度分别提高了24.5%和55.8%。偏光显微镜观察结果显示,在DCP/TAIC交联体系作用下,PP发泡材料表面光滑,泡孔细密且均匀一致。 相似文献
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F. J. Moscoso-Sánchez O. J. Ríos Díaz J. Flores L. Martínez V. V. A. Fernández A. Barrera G. Canché-Escamilla 《Polymer Bulletin》2013,70(3):837-847
Morphology, mechanical properties and crystallinity of foamed and unfoamed composites polypropylene (PP) and cellulose from Agave tequilana were studied. The PP–cellulose composite with PP–g-MA as coupling agent was obtained using a twin-screw extruder. Foamed composite was obtained by blending the composite with a blowing agent and moulding by compression. The morphology of the foamed composite, observed by SEM, shows that the bubble diameters were smaller when cellulose content increased. Young's modulus and impact of foamed and unfoamed PP/PP–g-MA composites were higher than the pure PP matrix, and they increase with the cellulose content. An increment of the crystallization percent was observed with respect at XRD analysis. This indicates that the cellulose acts as a nucleation agent, favouring the crystallization in the composites. 相似文献
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