Properties of Chitosan-Filled Polypropylene (PP) Composites: The Effect of Acetic Acid

The main objective of this research was to investigate the effect of chitosan content and chemical modification with acetic acid on mechanical and thermal properties of PP/Chitosan. It was found that the tensile strength, elongation at break and crystallinity of untreated PP/Chitosan composites decreased with increasing filler content; however, Young's modulus and thermal stability increased. The treated chitosan with acetic acid have improved the tensile strength and Young's modulus of PP/Chitosan composites. The thermal analysis results show that chemical modified chitosan had increase thermal stability and crystallinity of treated PP/Chitosan composites. The scanning electron microscopy (SEM) study of the tensile fracture surface of treated PP/Chitosan composites indicated that the presence of acetic acid increased the interfacial interaction between chitosan and polypropylene matrix.     

聚丙烯的化学改性

介绍了聚丙烯的共聚改性、接枝改性、交联改性、氯化改性四种化学改性方法,比较了这些化学改性方法的优缺点、对聚丙烯性能的改善情况以及研究进展,展望了聚丙烯化学改性的前景。     

竹纤维增强PP复合材料的研究

介绍了竹纤维增强聚丙烯(PP)复合材料的性能,初步探讨了竹纤维的处理、未处理以及纤维含量对增强PP的力学性能的影响因素。实验证明:与PP材料相比,添加竹纤维可使复合材料的力学性能有不同程度的改善,特别是对复合材料的冲击强度、拉伸强度及断裂伸长率影响较明显。     

改善聚丙烯机械性能的方法

聚丙烯是一种用途广泛的高分子材料,具有综合性能优良和易于加工等特点,但同时也具有耐寒性差,抗蠕变性差等缺点。对聚丙烯进行改性研究以改善其机械性能,对于扩展其应用领域具有重要的意义。本文从晶型改变、添加弹性体作为填充剂、玻纤增强、化学交联以及制备高分子纳米复合物等五个方面综述了改善聚丙烯机械性能的方法。     

凹凸棒土表面改性及其对聚丙烯力学性能的影响

使用硬脂酸钠、硅烷和钛酸酯偶联剂对凹凸棒土进行了表面改性,通过熔融共混法制备PP/凹凸棒土复合材料。借助FTIR、DSC、TEM、材料力学实验机等手段分别对凹凸棒土的改性效果、分散状态以及复合材料的结构与性能进行了研究。结果表明,适当的表面修饰有助于凹凸棒土在PP基体中实现以针状棒晶为基本形态的均匀分散;凹凸棒土在基体中提高了PP结晶度的同时提高了材料的强度和模量。     

超分散剂对聚丙烯复合材料性能的影响

以丙烯酸甲酯,二亚乙基三胺及硬脂酸等为原料,合成超支化分散剂(HBPL),采用傅立叶红外光谱(FT-IR)对其结构进行表征。结果表明:经HBPL改性后,聚丙烯/CaCO3复合材料的界面相容性得到很大的提高,冲击强度、弯曲强度分别比未经分散剂改性粉体的复合材料提高了50.2%和8.8%,复合材料的结晶形态基本保持不变,并采用扫描电镜(SEM)观察复合材料的冲击断面形貌。     

表面改性对聚丙烯/微米氢氧化镁复合材料性能的影响

研究了表面处理剂（钛酸酯和硅烷偶联剂）和原位聚合方法对聚丙烯/微米氢氧化镁（MH）复合材料的力学性能及流变性能的影响。采用DSC、SEM和毛细管流变仪对PP/MH（80/20）复合材料的性能进行了研究。结果表明：原位聚合改性后的微米MH与PP基体间的界面黏结力得到了加强,复合材料的冲击强度较填充未改性MH的复合材料提高了26.4 ％。在PP基体中添加聚合物包覆改性微米MH粒子的复合材料熔体流动速率较纯PP上升了64 ％。在相同剪切速率下,填充聚合物包覆改性MH的复合材料熔体表观黏度明显低于填充未改性微米MH的复合材料,表明聚合物包覆改性后的MH降低了其对PP熔体流动的阻碍作用,改善了PP/MH复合材料的流动性能。     

Properties of Paper Sludge Filled Polypropylene (PP)/Ethylene Propylene Diene Terpolymer (EPDM) Composites: The Effect of Silane-Based Coupling Agent

Paper sludge was used as a filler in PP/EPDM composites and 3-aminopropyl triethoxysilane (3-APE) was used in this study as a coupling agent. The effects of filler loading and 3-APE on the mechanical properties, water absorption, morphology, and thermal properties of the composites were investigated. It was found that incorporation of a silane coupling agent (3-APE) increased the stabilization (equilibrium) torque, tensile strength, and Young's modulus but decreased the elongation at break and water absorption. Scanning electron microscopy (SEM) study of the tensile fracture surface of the composites indicated that the presence of 3-APE increased the interfacial interaction between paper sludge and PP/EPDM matrix. The addition of a silane coupling agent also increased the crystallinity of PP and thermal stability of PP/EPDM/PS composites.     

Mechanical Properties of Plasma Surface-Modified Calcium Carbonate–Polypropylene Composites

Calcium carbonate was surface-modified by plasma-polymerized acetylene and the effect of surface modification on the mechanical properties of calcium carbonate–polypropylene composites was investigated. Two different plasma polymerization conditions were selected and applied. Chemical structures of plasma-polymerized acetylene products were identified. Mechanical and thermal properties of the composites prepared were evaluated and the effects of surface modification on the extent of adhesion of filler to the matrix, as well as on polymer phase, were investigated with the help of scanning electron microscopy. Some of the composite samples prepared with surface-modified calcium carbonate are found to yield higher percentage elongations and are mechanically superior compared to those prepared with unmodified filler. © 1997 SCI.     

聚丙烯/纳米CaCO3复合材料的拉伸性能

采用2种填料粒子表面处理方法[（表面活化（SI）和钛酸酯偶联剂处理（SII）]分别制备了纳米级CaCO3填充聚丙烯复合材料。应用万能材料试验机在室温下考察TCaCO3粒子表面处理和CaCO3含量对复合材料拉伸力学性能的影响。结果表明，随着纳米粒子CaCO3体积分数（φ）的增加，2种试样的弹性模量和拉伸强度有轻微的变化，而粒子表面处理的影响不太明显。当φ为0．5％时，SI的拉伸断裂强度达至最大，然后随着φ的增加呈非线性函数形式下降；除个别测量点外，SII的拉伸断裂强度基本上随着φ的增加呈非线性函数形式下降。在相同的条件下，SI的拉伸断裂强度高于SII，而断裂伸长率则相反。     

聚丙烯的改性研究进展

文章介绍了聚丙烯(PP)化学改性和物理改性的各种方法,其中包括共聚改性、接枝改性、交联改性、共混改性、增强改性、填充改性,综述了各种改性方法的最新成果和研究进展。     

聚丙烯/硅灰石复合材料的改性

综述了近年来国内外关于硅灰石改性聚丙烯(PP)过程中表面处理、工艺条件对PP/硅灰石复合材料性能的影响以及硅灰石与乙烯辛烯共聚物（POE）、部分氢化聚苯乙烯丁二烯共聚物（SEBS）等材料复合改性PP的研究现状,并展望了PP/硅灰石复合材料的发展前景。     

聚丙烯/云母复合材料改性研究进展

综述了国内外聚丙烯(PP)/云母复合材料改性研究的最新进展,包括改变云母粒径、加入相容剂、表面改性、加入增韧剂等方法。结果认为,各种改性方法均可使PP/云母复合材料的力学性能相对于纯聚丙烯大幅度提高。最后展望了今后PP/云母复合材料研究亟待解决的问题和发展方向。     

滑石粉对聚丙烯木塑复合材料性能影响的研究

研究了不同含量的滑石粉对聚丙烯木塑复合材料力学性能和加工性能的影响.结果表明:滑石粉能够在一定程度上改善聚丙烯木塑复合材料的力学性能和加工性能.硅烷偶联剂对复合材料的处理效果要优于钛酸酯偶联剂.     

无机填料对PP木塑复合材料物理力学性能的影响

为了利用无机填料开发出更加高效、环保、友好的新型木塑制品,考察了无机填料种类及含量对木塑复合材料物理力学性能的影响.以杨木粉纤维、聚丙烯(PP)、碳酸钙、硅灰石、硅藻土为原料,采用熔融共混和热压成型的方法制备PP木塑复合材料,测试并分析了复合材料的弯曲性能、吸水率、吸水厚度膨胀率和表面耐磨性能.结果表明,随着无机填料含...     

壳聚糖的化学改性研究

壳聚糖是一种新型功能材料,在生物工程、医药、日常化学品、废水处理等方面得到广泛应用。为改善其溶解性较差,稳定性较弱等缺点,扩大其应用范围,常采用物理和化学的方法对壳聚糖改性。文章综述了壳聚糖的化学改性方法并展望其发展前景。     

纳米级碳酸钙填充聚丙烯复合材料的弯曲和耐热性

采用两种填料粒子表面处理方法(表面活化(SⅠ)和钛酸酯偶联剂处理(SⅡ))分别制备了纳米级碳酸钙(CaCO3)填充聚丙烯复合材料。应用万能材料试验机在室温下考察了表面处理方法及粒子含量对复合材料弯曲性能的影响。结果表明,随着纳米粒子体积分数(Фf)的增加,SⅠ的弯曲模量和弯曲强度有所提高;而SⅡ则轻微下降。应用热变形温度仪测量了试样的热变形温度(HDT)后发现,纳米CaCO3粒子的填充可明显地改善PP树脂的耐热性能。在较高的载荷下,两种PP／纳米CaCO3复合体系的热变形温度十分接近。     

PP/PET复合材料改性研究进展

对近几年改性聚丙烯(PP)基和PP/聚对苯二甲酸乙二酯(PET)复合材料中使用改性剂的改性方法及改性剂在复合材料中的应用研究进行了综述,按改性剂结构将改性剂改性的方法分为非纤维化改性、纤维化改性和成核剂改性三大类。其中非纤维化改性包括单体改性和共单体改性;纤维化改性包括PET短纤维改性、碳纤维改性和玻璃纤维改性;其它改性包括激光焊接改性。比较了各种改性方法的优缺点,并对PP/PET复合材料中改性剂改性方法的发展进行了展望。     

The Mechanical Properties and Chemical Resistance of Short Glass-Fiber-Reinforced Epoxy Composites

ABSTRACT

Epoxy–short glass fiber composites were prepared by directly blending two-pack system of Araldite (CY-230) and hardner (HY-951) with short glass fibers. The short glass fiber content was varied from 2% to 10% by weight of the total matrix. These composites were then characterized for morphology using scanning electron microscopy, mechanical properties, that is, tensile and flexural properties and resistance toward various chemicals. The epoxy-glass fiber composites showed improved tensile and flexural properties but increased dispersion among the properties with increasing fiber content. Several reasons to explain these effects in terms of reinforcing mechanisms were discussed. These composites were stable in most chemicals but were completely destroyed in concentrated sulfuric acid, nitric acid, and pyridine.     

改性纳米CaCO3/PP动态力学性能的研究

熔融制备了反应性单体改性纳米CaCO3/PP复合材料,用DMA研究了反应性单体对纳米CaCO3/PP复合材料动态力学性能的影响.结果表明纳米CaCO3的加入提高了PP的储存模量E′和损耗模量E″,降低了E″的峰温和β转变温度.丙烯酸AA改性有降低复合材料的E′和E″的作用,但不明显影响转变温度.苯乙烯St或与AA混合改性明显提高复合材料的E′和E″,也明显地降低E″的峰温.不管是否对反应性单体改性,纳米CaCO3加入均使PP的β转变温度移向低温.