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介绍了兰州石化聚丙烯装置,开发与生产高抗冲共聚产品SP179的主要工艺参数、产品结构和性能。同时确定了聚丙烯环管工艺生产超高抗冲产品的技术指标,最后对SP179产品做出了全面的性能测试。 相似文献
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采用环酮类过氧化物3,6,9-三乙基-3,6,9-三甲基-1,4,7-三过氧壬烷(Cyclic),芳香族过氧化物过氧化二异丙苯(DCP)和脂肪族过氧化烷烃2,5-二甲基-2,5(二叔丁基过氧基)己烷(D25)通过反应挤出制备熔体质量流动速率分别为20 g/10 min和30 g/10 min左右的高流动抗冲聚丙烯(PP).对产物的形态结构与力学性能进行了分析.结果表明:hiPP/Cyclic体系降解产物的冲击性能明显优于hiPP/D25和hiPP/DCP体系.结合热分析(DSC)和扫描电子显微镜(SEM)观察表明:hiPP/Cyclic降解产物的分散相尺寸小,分布均匀,和基体PP具有良好的相容性,是导致其冲击性能较好的主要原因. 相似文献
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反应器内合金化技术生产高抗冲聚丙烯(hiPP)过程中,目前工业上普遍采用加入低纯氮(LPN)的方式阻止聚丙烯颗粒表面生成乙丙橡胶的防粘策略,限制了乙烯含量的提高,使得其抗冲性能受到一定的制约。提出了一种在共聚气相釜中原位添加极少量(<0.1%)超细粉体的方法,通过局载化于聚丙烯颗粒表面,从而起到替代低纯氮的作用,并能通过物理阻隔的方式进一步防止颗粒间发黏聚并,成功将其运用于Hypol 工艺,制得高乙烯含量(>20%)且流动性良好的hiPP。同时,将产物与传统低纯氮体系的进行比较,其常温抗冲性能由36.44 kJ·m-2升至60.56 kJ·m-2,低温抗冲性能由14.78 kJ·m-2 升至35.12 kJ·m-2,体现出其优异的常温和低温抗冲性能。 相似文献
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Spheripol工艺生产高抗冲聚丙烯 总被引:1,自引:0,他引:1
介绍了Spheripol工艺生产高抗冲聚丙烯产品的方法,采用两步复合工艺生产嵌段聚丙烯,第1步采用环管反应器进行丙烯液相均聚反应,第2步采用流化床反应器进行丙烯均聚物与乙烯单体气相共聚反应,即在气相反应器中,利用来自环管反应器中的均聚物的残余活性,加入乙烯和补充的丙烯及氢气实现乙-丙共聚,共聚物的生成使最终产品的抗冲性能大大提高,尤其是低温下的抗冲性能。 相似文献
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透明高抗冲聚苯乙烯树脂的工业化试验 总被引:1,自引:0,他引:1
在5kt/a高抗冲聚苯乙烯树脂装置上,以1,1-双(叔丁基过氧基)环己烷为引发剂、苯乙烯为单体、丁二烯-苯乙烯嵌段共聚物(简称K树脂)为增韧剂,采用自由基聚合工艺生产了透明高抗冲聚苯乙烯(HT-IPS)树脂,考察了HT-IPS树脂的微观结构、相对分子质量及其分布、流变性能、接枝反应程度、物理机械性能和光学性能,讨论了影响HT-IPS树脂结构及性能的因素。结果表明,HT-IPS树脂具有微观相分离结构,聚丁二烯链段为分散相、聚苯乙烯链段为连续相;HT-IPS树脂的流动性能略差于高抗冲聚苯乙烯树脂,且随着K树脂用量的增加,其流动性能变差,K树脂用量应控制在15份以下;在聚丁二烯链段的主链和侧链均发生了接枝反应,HT-IPS树脂具有较高的弯曲强度、弹性模量和拉伸强度,其光学性能、流变性能良好,但冲击强度较低,扯断伸长率较小。 相似文献
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The multiphase morphology of high impact polypropylene (hiPP), which is a reactor blend of polypropylene (PP) with ethylene–propylene copolymer, was investigated by transmission electron microscopy, selected area electron diffraction, atomic force microscopy, and field‐emission scanning electron microscopy techniques in conjunction with an analysis of the hiPP composition and chain structure based on solvent fractionation, 13C‐NMR, and differential scanning calorimetry measurements. A multilayered core–shell structure of the dispersed phase of hiPP in solution‐cast films and the bulk was observed. The inner core was mainly composed of polyethylene (including its long blocks) together with part of PP, the intermediate layer was ethylene–propylene random copolymer, and the outer shell consisted of ethylene–propylene multiblock copolymers. The formation process and controlling factors of the multilayered core–shell structure are discussed. This kind of multiphase morphology of hiPP caused the material to possess both a high rigidity and high toughness. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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Mass transfer resistance in the production of high impact polypropylene (hiPP) produced by a two-stage slurry/gas polymerization was investigated by field-emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. It is found that the formation of ethylene-propylene copolymer (EPR) phases in polypropylene (iPP) particle produced in the first stage slurry polymerization exhibits a developing process from exterior to interior. During the early stage of ethylene-propylene copolymerization, with lower content of copolymerized ethylene (7.4 mol%), the EPR phases occur only in the external layer of the particle, while at the later stage of the copolymerization with higher content of copolymerized ethylene (26.7 mol%), the elastomer phases distribute uniformly in the whole particle. This phenomenon is due to an effect of mass transfer resistance. The origin of mass transfer resistance is loosely agglomerate inclusions of low tacticity polypropylene within the semi-filled micropores inside the iPP particle. It is the inclusions inside the micropores that resist the diffusion of ethylene/propylene comonomers into the particle. 相似文献
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研究了乙丙嵌段共聚聚丙烯(PP-B)管材专用树脂的结构与性能。PP-B具有典型的乙丙嵌段共聚物序列结构,是含有丙烯均聚物(PP-H)、乙丙橡胶(EPR)及可结晶乙丙共聚物的抗冲聚丙烯(PP);其中,均聚物与共聚物比例合理,形成的EPR多、粒径小,对提高冲击强度有利。提高PP-H的质量分数和等规指数,可有效提高PP- B的刚性。PP-B的熔点与PP-H近似;相对分子质量分布较宽,流变性能好;微观与亚微观结构合理,宏观性能优良。 相似文献
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The functions of crystallizable ethylene‐propylene copolymers in the formation of multiple phase morphology of high impact polypropylene (hiPP) were studied by solvent extraction fractionation, transmission electron microscopy (TEM), selected area electron diffraction (SAED), nuclear magnetic resonance (13C‐NMR), and selected reblending of different fractions of hiPP. The results indicate that hiPP contains, in addition to polypropylene (PP) and amorphous ethylene‐propylene random copolymer (EPR) as well as a small amount of polyethylene (PE), a series of crystallizable ethylene‐propylene copolymers. The crystallizable ethylene‐propylene copolymers can be further divided into ethylene‐propylene segmented copolymer (PE‐s‐PP) with a short sequence length of PE and PP segments, and ethylene‐propylene block copolymer (PE‐b‐PP) with a long sequence length of PE and PP blocks. PE‐s‐PP and PE‐b‐PP participate differently in the formation of multilayered core‐shell structure of the dispersed phase in hiPP. PE‐s‐PP (like PE) constructs inner core, PE‐b‐PP forms outer shell, while intermediate layer is resulted from EPR. The main reason of the different functions of the crystallizable ethylene‐propylene copolymers is due to their different compatibility with the PP matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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A commercial high‐impact polypropylene (hiPP) was fractionated by temperature‐gradient elution fractionation into nine fractions. All fractions were studied using Fourier transform infrared spectroscopy and differential scanning calorimetry. The amount of ethylene in the fractions was also determined. The results demonstrate that the ethylene–propylene statistical copolymer (or ethylene–propylene rubber, EPR) content in this hiPP is rather low and the amounts of ethylene–propylene segmented copolymer and ethylene–propylene block copolymer (that act as adhesive and compatibilizer between elastomeric phase and matrix, respectively) are negligible. Furthermore, the morphology of the resin was studied using scanning electron microscopy observations of microtome‐cut original and etched samples, which reveals that EPR particles are too large and their distribution inside the matrix is not uniform. Copyright © 2010 Society of Chemical Industry 相似文献
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In this paper, the pristine basic morphology of high impact polypropylene (hiPP) particles prepared with an industrial MgCl2/TiCl4 Ziegler–Natta catalyst undergoing sequentially occurred propylene (P) homopolymerization and ethylene (E)/propylene copolymerization has been probed mainly using transmission electron microscopy (TEM) techniques including plain TEM and the advanced transmission electron microtomography (TEMT). It is revealed that the basic structure units comprising a whole hiPP particle are the submicron PP (polypropylene) globule and nano-sized EP (ethylene-co-propylene) droplet. EP rubber (EPR) domain is formed by the agglomeration of EP droplets. Continually formed EP droplets turn to fill, from inside out, the micro- and macro-pores inside the preformed PP skeleton, affording different-sized EPR domains. Taking the two basic structure units into account, new quaternary structure model describing the manifold structures of hiPP particles has been proposed. From these findings, it is suggested that, to gain hiPP polymers with excellent stiffness/toughness-balanced properties, it is crucial to control the first-staged propylene homopolymerization alongside a rational design of the catalyst architecture to accomplish desired EPR dispersion morphologies that dictate hiPP properties. 相似文献
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汽车用高流动性共聚聚丙烯的结构与性能 总被引:1,自引:0,他引:1
采用溶剂萃取分离的方法将汽车用高流动性共聚聚丙烯分成以乙丙橡胶为主要成分的可溶物和以等规聚丙烯为主的不溶物2个级分。用红外光谱,核磁共振碳谱、凝胶渗透色谱、偏光显微镜、原子力显微镜等测试手段,分析研究了各级分的链结构、聚集态结构,相态结构等,并与国外试样进行比较。结果表明:开发的汽乍用高流动性共聚聚丙烯中乙烯含量,橡胶含量以及橡胶中乙烯含量均较高,且乙烯在分子链上的分布均匀、合理,有效地提高了产品的抗冲击性能;不溶物立构规整性好、结晶度高.保持了材料的良好刚性。 相似文献
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Norio Manabe Yoshimitsu Yokota Hisayuki Nakatani Shoutarou Suzuki Liu Boping Minoru Terano 《Polymer Bulletin》2005,54(1-2):141-145
Summary In this study, the thermal oxidative degradation of a polypropylene (PP) impact copolymer was examined using a transmission electron microscope equipped with an energy dispersive X-ray system (TEM/EDX). The oxidative behavior was visually captured by oxygen line analysis. The oxidation resistance of the ethylene-propylene rubber (EPR) phase was considerably higher than that of the PP matrix, indicating that the degradation behavior of the PP impact copolymer was heterogeneous. It was found that the higher resistance of the EPR phase originated from its primary structure by 13C-NMR measurement. 相似文献