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1.
气相法聚乙烯工艺技术进展   总被引:1,自引:0,他引:1  
李贺  王 《弹性体》2000,10(1):46-56
介绍了国内外气相聚乙烯装置及工艺概况、气相工艺技术进展,并对我国气相聚乙烯的发展提出了建议.  相似文献   

2.
本文从Unipol气相法工艺聚乙烯装置原料风险、职业卫生风险、人员风险和某聚乙烯装置工艺操作过程安全事件,对装置中存在的风险因素进行分析,并提出对策。  相似文献   

3.
HDPE工艺技术进展   总被引:5,自引:1,他引:5  
介绍了高密度聚乙烯生产技术即淤浆法,气相法、溶液法,综述了各自的特点,工艺路线,产品方案。尤其是双峰高密度聚乙烯技术的发展。  相似文献   

4.
胜喜梅 《河南化工》2000,(12):17-18
分析了气相流化床聚乙烯生产过程中影响聚乙烯单耗的因素,提出了通过改变有关工艺操作条件以降低乙烯单耗的措施。  相似文献   

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BP高产气相聚乙烯工艺Innovene开始转让设计第一个采用BP化学公司高产气相聚乙烯工艺“Innovene”的基础装置正在设计之中,建设地点最有可能是在亚洲,用户可能是中国石化总公司和台塑。装置如果在1996年获得批准,1998年就动工,单一反应器...  相似文献   

6.
介绍了5种适用于Unipol气相法聚乙烯工艺的国产催化剂的制备技术路线及其在装置上的应用情况,提出了今后开发Unipol气相法聚乙烯催化剂的建议。  相似文献   

7.
聚乙烯技术新进展   总被引:7,自引:0,他引:7  
评述了双峰聚乙烯技术,茂金属催化剂和采用液态冷凝技术的乙烯气相聚合工艺的新进展。介绍了生产双峰聚乙烯产品的各种双反应器工艺和单反应器工艺,指出双反应器工艺是目前国际上采用最广泛的工艺,而单反应器工艺目前仍处于开发试验中,是生产双峰聚乙烯产品未来发展方向。液态冷凝气相聚乙烯工艺利用冷凝液体的蒸发潜热及时移走反应热,极大地缓和了反应器散热问题,使得反应器单位体积的聚乙烯产量得到大幅度提高。将液态冷凝技术与超高活性的茂金属催化剂配合使用是当今研究的一个热点。  相似文献   

8.
叙述和分析了90年代以来世界聚烯烃工业的重点技术,包括高效催化剂技术,无溶剂聚合技术,气相流化床聚乙烯工艺的冷凝态进料技术,共聚技术,生产分子量双峰分布聚乙烯树脂技术以及不造粒技术。  相似文献   

9.
利用气相流化床生产聚乙烯和聚丙烯的工艺技术已经广泛使用。用此技术商业化生产EP-DM开始于1997年。由于催化剂对产品和工艺的限制,阻碍了早期气相EPDM的大规模生产。  相似文献   

10.
本文主要是分析了聚乙烯的生产制造工艺,包括高压法、低压法和中压法三种,对管式高压法生产和气相低压法生产的工艺进行讨论,分析生产中存在的危险,对危险性进行对比。  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

15.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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