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61.
茂金属催化剂是近年出现的新型催化剂,技术进步很快。应用此催化剂生产的聚烯烃产量快速增加,正逐渐挤占非茂金属聚烯烃市场,而国内还没有茂金属聚烯烃的生产,产业前景广阔。推介了国外发展该技术及其产业的一些做法。  相似文献   
62.
PP塑料底材处理剂的研制及应用   总被引:1,自引:0,他引:1  
以氯化聚丙烯为主要原料,制备了一种环保型的聚丙烯塑料底材表面处理剂。讨论了树脂基料、溶剂、乳化剂的选取及配比等因素对涂层附着力的影响,确定了处理剂的最佳配方。经试验测试,聚丙烯塑料表面经处理剂处理后,其涂层的附着力显著提高。  相似文献   
63.
The tensile properties of polypropylene (PP) filled with hollow glass beads have been measured at room temperature to identify the effects of the particle contents, size and its distribution on them in the present article. The mean diameters of the fillers were 11, 35, and 70 μm, and they were named as TK10, TK35, and TK70 respectively. The surface of these particles was pretreated with silane coupling agent. The results showed that the yield stress (σy) decreased gently for PP/TK70 systems, whereas decreased relatively obviously for PP/TK35 systems with increasing the volume fraction (?f) of the fillers. When ?f was less than 5%, the tensile strength at break (σb) of the composites increased with the increase of ?f. When ?f was more than 5%, σb was almost a constant for PP/TK70 systems, while σb decreased linearly for PP/TK35 systems. The tensile fracture strain (εb) of the composites decreased suddenly when ?f was less than 5%, and then decreased slightly with increasing ?f. When ?f was 10%, σy and σb increased while εb decreased with the increase of the bead diameter. Furthermore, the σy was predicted by means an equation proposed in the previous work, and good interfacial adhesion was shown between the hollow glass beads and the matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1697–1701, 2007  相似文献   
64.
将Ziegler-Natta高效载体催化剂YS—842在Hypol工艺聚丙烯(PP)中试装置上进行应用考核,考察了该催化剂的适应性及共聚合性能。试验表明,YS—842催化剂活性高(达1.2Mg/g)、寿命长、氢调敏感性好:用YS—842催化剂生产的聚合物流动性好,粒径分布窄,细粉少,平均粒径为640μm;等规指数大于98.5%,堆密度大于0.45g/mL;试生产的F401、J340,其机械性能与使用进口催化剂生产的产品相当。  相似文献   
65.
聚丙烯在功能纤维领域中的发展   总被引:2,自引:0,他引:2  
阐述了聚丙烯在功能纤维中的应用、功能纤维的分类及国内外功能性聚丙烯纤维的发展状况,具体介绍了几种典型的聚丙烯功能纤维,并对聚丙烯在功能纤维中的发展趋势进行了分析。  相似文献   
66.
The effects of ultrasonic irradiation on the rheology, structure, and properties of PP/inorganic filler composites were studied. Scanning electron microscopy showed that ultrasound increased the orientation degrees of acicular fillers to the flow direction. WAXD indicated that ultrasound vibration induced sheet fillers orient with its surface perpendicular to the direction of the ultrasound vibration. The orderly rearrangements of fillers in the polymer melt induced by ultrasound vibration can reduce the steric hindrances in the flow field and increase the flowability of the PP/inorganic filler composites. The effect of ultrasound on reducing the apparent viscosities is very prominent, especially at lower shear rate. Ultrasound has an even more marked effect on reducing the apparent viscosities of composites containing fillers of larger size. With ultrasound vibration, the mechanical properties of the composites are also improved because of the orientation and uniform dispersion of fillers in the matrix. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1553–1560, 2005  相似文献   
67.
The nucleating ability of two organic pigments, quinacridone and phthalocyanine, in nonisothermal polypropylene (PP) crystallization was investigated. The investigations were carried out using DSC and polarizing microscopy. The efficiency of pigments in the nucleation process was determined in a simple test comparing the crystallization temperature of the PP‐containing pigments with respect to the pure polymer. Both pigments revealed good nucleating activity. In the presence of pigments the increment of the crystallization temperature and the increase of nucleation rate were observed. The nucleating efficiency of pigments was confirmed in investigations of the obtained structure. The nucleating activity of pigments was explained by their features fulfilling several requirements for good nucleating agents. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3957–3964, 2003  相似文献   
68.
Nanocomposite powders from polypropylene filled with surface modified and unmodified fumed silica have been prepared from polymer solution to achieve improved mixing and have been forwarded to fiber melt spinning. The surface of the fumed silica was modified with dodecyl alkoxy silanes. Crystallization velocity and viscosity of the PP nanocomposites thereof were determined to ensure good melt spinning processing conditions for all composite compositions. Upon addition of untreated filler particles, a shear thinning and an increased crystallization velocity of the polymer melt was found, while only minor changes were detected in the presence of surface modified fumed silica particles. The composites and the polymer fibers made from these powder composites by melt spinning were mainly characterized by optical microscopy (OM), scanning electron microscopy (SEM), mechanical measurements, differential scanning calorimetry (DSC), and solid‐state NMR. The unmodified fumed silica was found to have a strong influence on the mechanical fiber properties, while the surface modified silica only a small one. Fibers were additionally characterized with respect to the uniformity, the PP crystallinity, moisture absorption, and the water contact angle. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 218–227, 2007  相似文献   
69.
介绍了日本三菱油化公司(现为三菱化学公司)BC-8嵌段聚丙烯的开发经过及实际结构。近年结构分析结果发现BC-8嵌段聚丙烯并非嵌段物,而是由均聚聚丙烯、EPR(乙丙橡胶)以及聚乙烯(链上有少量丙烯单元但并非嵌段物)三者组成的高分子合金。  相似文献   
70.
弹性纳米粒子/纳米TiO2/聚丙烯复合材料的研究   总被引:3,自引:0,他引:3  
采用专利技术制备了弹性纳米粒子(ENP)/纳米二氧化钛(TiO2)复合材料,并使用这种复合材料改性聚丙烯(PP),制备了具有较高韧性和较好灭菌性能的PP纳米复合材料。当丁苯ENP的用量为2%,平均粒径为50nm的金红石型TiO2用量为1%时,所研制的PP纳米复合材料的冲击强度可提高30%以上,灭菌率可达60%。  相似文献   
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