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1.
介绍聚丙烯(PP)片材专用料中复合助剂体系的研制过程、专用料的生产过程及其片材的加工过程,讨论了加工温度对透明PP片材光学性能的影响,确定了透明PP片材的最佳加工温度为230℃。同时对透明PP片材专用料的使用性能和加工性能进行了评价。经用户使用表明,透明PP片材的韧性和刚性均衡,制品外观光滑、透明,能满足使用要求。  相似文献   

2.
以均聚聚丙烯(PP)为基础树脂,通过加入成核剂生产透明PP片材专用树脂。探讨了成核剂的加入量及片材加工温度对片材透明性能的影响,确定PP片材最佳加工温度为230℃。成核剂的加入使PP的结晶度由 44.1%提高到51.4%,结晶温度、熔点等均有不同程度的提高。  相似文献   

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以均聚聚丙烯(PP)为基体树脂,通过添加成核剂制备了注塑级透明PP专用料。成核剂的加入.不但改善了PP的光学性能,而且提高了PP的刚性,在某种程度上改善了其加工性能。为降低生产成本和提高透明PP的性能,研制了复配成核剂体系,添加该成核剂生产的透明PP的各项性能均达到技术指标;并讨论了加工温度和树脂熔体流动速率对透明PP光学性能的影响。  相似文献   

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无规共聚透明聚丙烯研究   总被引:4,自引:0,他引:4  
研究了乙烯含量对无规共聚聚丙烯性能的影响,添加透明剂后的无规共聚透明PP,无规共聚透明PP中的乙烯含量至少在3%(质量)以上,专用料的透明度和其他的性能良好。借助毛细管流变仪,对扬子石化股份公司研究院研制的无规共聚透明聚丙烯专用料的流变性能进行了测试,提出了对专用料加工条件的建议。  相似文献   

5.
利用正交设计方法对生产高透明聚丙烯片材的工艺条件进行试验设计,考察了机头加工温度、中辊温度及包辊时间对PP片材透明度的影响。结果表明,口模温度250℃、包辊时间15s、中辊温度55℃为生产高透明PP片材的最佳工艺参数,所得片材的雾度只有13.2%,属高透明产品。  相似文献   

6.
国内市场透明聚丙烯的性能与分析   总被引:3,自引:0,他引:3  
介绍了透明聚丙烯(PP)专用料的国内市场现状、牌号、性能,着重分析了扬子石化公司透明PPJ301G,提出扬子石化公司应重点开发无规透明PP专用料以及中高熔体流动速率无规透明PP专用料的设想,并为工业化无规PP中低熔体流动速率的专用料提出理化分析数据。  相似文献   

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借助毛细管流变仪,对扬子石油化工股份有限公司研究院研制的无规共聚透明聚丙烯(PP)专用料的流变性能进行了测试,并结合专用料的相对分子质量及其分布情况,对专用料的流变行为进行分析比较,结果表明:不同的基料对材料的加工性能影响不大,不同基料的相互替换不影响专用料的加工工艺,并对专用料加工条件提出了建议。  相似文献   

8.
重点介绍重型汽车侧护板用改性PP专用料的研制。考察了PP基体树脂和各种改性成分,如增韧剂、填充剂、过氧化物等对专用料综合性能的影响,并研究了挤出加工工艺对专用料性能的影响,确定了最佳工艺参数和配方。使用这种改性PP专用料制成的重型汽车侧护板完全满足性能要求,并已经成功地应用在一汽奥威重型汽车上。  相似文献   

9.
介绍了电石法PVC透明片材专用料在105 m~3聚合釜上的生产概况,针对下游客户在加工过程中出现的问题对配方、生产工艺进行了优化,最终产品质量达到了乙烯法PVC透明片材专用料的指标,可用于生产高档透明片材制品。  相似文献   

10.
《塑料加工》2006,41(3):14-14
随着人们生活水平不断提高,必然带来在文化、娱乐、食品、医疗、材料、居室装饰等各个方面不同变化的要求与提高,市场中很多物品越来越多地使用透明材料。因此,开发透明PP专用料是一个很好的发展趋势,尤其需要透明性高、流动性好,成型快的PP专用料,以便设计加工成人们喜爱的PP制品。透明PP比普通PP、PVC、PET、PS更具特色,有更多优点和开发前景。  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   

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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   

18.
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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