注塑成型新技术的发展概况

综述了近年来注塑成型技术的发展状况,介绍了新型气辅注塑成型、多组分注塑成型、粉末注塑成型、微孔发泡注塑成型、微注塑成型等技术的特点及最新动向。     

高分子材料注塑成型技术应用及发展趋势

综述了国内外几种注塑成型新方法和趋势。包括注塑成型计算机辅助工程(CAE)、气辅注塑成型、快速热循环注塑成型和微孔发泡注塑成型等技术的特点、研究现状和应用领域,并对发展方向进行了展望。     

微孔发泡注塑技术研究进展

介绍了微孔发泡塑料的定义及优点,阐述并对比了物理微孔发泡和化学微孔发泡等2种微孔发泡注塑成型工艺;详细介绍了近年来微孔发泡注塑技术在工艺优化、开模二次发泡、表面质量改善和力学性能预估等方面的最新研究进展;最后,对微孔发泡注塑技术未来的研究方向进行了展望。     

微孔发泡注塑产品的特点以及生产技术改进

微孔发泡注塑产品具有一定的特点,其利用微孔直径小,且成型产品污染小,是一种绿色环保型材料。本文主要分析微孔发泡注塑产品成型特点,并且介绍这种微孔发泡注塑产品在实际生产活动中应用具有的一定优势。最后根据这种微孔发泡注塑产品成型的生产技术进行分析,了解这种生产技术原理,并且针对生产技术中还存在的问题,提出一些改进生产技术的方法和措施。希望能通过本文的介绍,帮助相关技术生产工作人员提供技术使用质量和效率,进而确保微孔发泡注塑产品的质量。     

微孔发泡注塑成型工艺及其设备的技术进展

微孔发泡注塑技术是实现塑料轻量化设计的重要途径.在简要回顾微孔塑料发泡注塑成型工艺的基础上,重点介绍了微孔发泡注塑成型设备的发展动向.从注气、塑化、注射、模具和辅助系统等五个模块,分析总结工艺要求及多种国外产业端的先进设备特点和解决方案.文中重点论述多个成功应用的生产设备创新案例,并对微孔发泡注塑成型技术和设备的未来发...     

微孔注塑成型研究进展

阐述了微孔发泡成型的基本原理,综述了注射速度、注射量、模具温度、熔体温度等加工参数对微孔注塑成型的影响,介绍了常见的微孔注塑成型设备,并对微孔注塑成型的发展前景进行了展望。     

汽车仪表板骨架微孔发泡塑件的综合性能

为了研究微孔发泡在大型塑件中的应用问题,以汽车仪表板骨架塑件为例,利用Moldflow软件模拟分析微孔发泡注塑和传统注塑成型。结果表明,微孔发泡注射成型在注塑时间、注塑压力、体积收缩和翘曲变形等方面均好于传统注塑成型。通过对塑件泡孔形貌、密度、孔隙率、力学强度、表面粗糙度等性能的检测,研究微孔发泡实际应用问题。检测结果表明,微孔发泡能够有效实现产品减重,且产品力学性能优于传统注塑,但表面粗糙度较传统注塑差,汽车外观零件如采用微孔发泡成型须经过表面处理来改善表面缺陷。     

微孔注塑制品表面质量改善和翘曲降低的技术

为拓宽微孔注塑制品的应用范围,需要改善其表面质量,降低其翘曲变形。模腔气体反压技术、模腔被动控温技术、微孔共注塑技术、泡孔成核速率控制技术、微孔注射压缩成型技术和快速热循环微孔注塑技术等可有效改善微孔注塑制品的表面质量。模腔气体反压技术、微孔共注塑技术和调整加工参数可进一步降低微孔注塑制品的收缩率和翘曲,提高制品的尺寸精度。本文较系统介的绍了这些技术和方法。     

微孔发泡注塑成型产品的表面质量与改进技术

表面质量是影响微孔发泡注塑成型产品使用效率的关键因素,而生产技术水平直接关系着表面质量,因此,加强技术研究,不断改进微孔发泡注塑成型产品生产技术具有重要的作用和意义。本文主要分析微孔发泡注塑成型产品的基本定义和概念,进入深入分析这种新型的加工工艺在成型过程中,其产品表面容易出现的质量问题,针对表面质量问题,为相关单位工作人员提供一些改进生产技术的方法和措施,希望能帮助有关技术人员提升工作质量。     

Testing System for Conformability and Comfortability of Double Star Professional Sport Shoes Has Beeen Ap praised

简要介绍了塑料的发泡注塑成型技术，并重点介绍了微孔泡沫注塑成型的原理，过程及应用前景。     

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。