连续纤维增强热塑性树脂预浸料的研究进展

本文总结了连续纤维增强热塑性树脂预浸料的发展及应用,分析了热塑性预浸料可选择的增强纤维和基体树脂,以及国外商业化热塑性预浸料的进展;讨论了热塑性预浸料不同制备技术的优缺点,重点阐述了熔融浸渍工艺实施的难点,并指出熔融浸渍和薄膜层叠法相结合的工艺是比较适合制备热塑性预浸料的成型方法。     

连续纤维增强热塑性复合材料的制备与成型

论述了连续纤维增强热塑性塑料片材(预浸料)的制备工艺以及连续纤维增强热塑性塑料制件的成型工艺,并评述了国内外连续纤维增强热塑性塑料制品生产工艺的进展。     

连续纤维增强热塑性预浸料制备工艺与发展趋势

总结了国内外连续纤维增强热塑性预浸料的主流浸渍及成型工艺,包括热熔法、溶液浸渍、粉末浸渍、薄膜堆叠、混编法、原位聚合等,对比了不同工艺在原料、设备、加工流程等方面的优缺点,并对热塑性预浸料成型模具的设计与应用进行了讨论;同时,阐述了热塑性预浸料的发展现状,介绍了更加轻量化的浸渍技术以及包括三维连续编织技术在内的多样化的...     

热塑性复合材料研究及其在航空领域中的应用

本文介绍了热塑性复合材料的分类与组成,并简述了短纤维粒料(SFT)、长纤维粒料(LFT)、玻璃纤维毡增强热塑性片材(GMT)、织物预浸料和单向连续纤维增强热塑预浸料(CFRTP)的各自优点,连续纤维增强热塑性树脂的预浸料的主流制备工艺。结合高性能热塑性复合材料在国外航空领域中的应用,展望了其在我国的发展方向。     

连续纤维增强热塑性预浸料制备工艺的研究进展

连续纤维增强热塑性复合材料综合性能优异,其应用与日俱增。作为热塑性复合材料制造用中间材料,连续纤维增强热塑性预浸料的制备和质量控制技术对于热塑性复合材料的发展来说至关重要。本文详细介绍了熔融浸渍法、溶剂浸渍法和粉末浸渍法三种工艺制备连续纤维增强热塑性预浸料的研究进展,总结了各种制备工艺的优缺点,并对高性能热塑性预浸料的发展趋势进行了展望。     

一种OOA成型中温固化环氧树脂芳纶纤维预浸料研究

研制一种OOA(非热压罐)成型中温固化环氧树脂芳纶纤维预浸料,对树脂进行流变性能和DSC分析,确定树脂的固化工艺。采用热熔法制备OOA成型芳纶纤维预浸料,通过真空袋法成型复合材料层压板,进行性能测试。结果表明,OOA成型中温固化环氧树脂芳纶纤维预浸料适合真空袋法成型复合材料,层压板孔隙率低,力学性能满足要求,复合材料玻璃化转变温度高,具有较好的耐热性。     

热塑性预浸带模压成型工艺研究

本文针对热塑性预浸带的模压成型工艺进行了探索研究，为成型连续纤维增强热塑性复合材料模压制品提供了简单，实用的工艺方法。     

值得关注的预浸料市场

预浸料是用控制量的树脂(热固性或热塑性)浸渍纤维或织物后形成的中间材料。浸渍技术有溶剂浸渍、热熔体浸渍、粉末浸渍等。预浸料可以"B阶"状态或部分固化后储存。预浸带或预浸布用于手糊、自动铺带、自动铺纤或某些缠绕成型工艺中。单向预浸带(所有纤维平行)是最常见的预浸料形式,它们提供单向增强。机织布及其他平面织物预浸料提供二维增强,它们一般成卷销售。还有用纤维预成型体和编织物制成的预浸料,它们提供三维增强。     

加工成复杂形状的预浸料坯

旭化成工业公司用自己的技术复合增强长纤维和热塑性树脂纤维,开发出可加工成复杂形状的纤维增强热塑性塑料预浸料坯“WIP”,而以往用预浸料坯成型复杂形状制品是困难的。WIP是由碳纤维及玻璃纤维等增强长纤     

复合材料在航空发动机风扇叶片上的应用综述

大涵道比涡扇发动机为不断减重,大量使用复合材料风扇叶片。本文综述了复合材料风扇叶片的发展与应用情况,总结了叶片各制造工艺的特点,包括预浸料手工铺放/热压罐固化成型工艺、预浸料自动铺丝/热压罐固化成型工艺、三维机织碳纤维增强树脂传递模塑(RTM)成型工艺。复合材料风扇叶片的制造工艺正朝着自动化、高精度的方向发展。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。