芳纶无纬布连续化生产工艺方法与研究

本文通过对芳纶无纬布连续化生产工艺方法的研究,探究不同的工艺条件(包括纱架上纤维退绕张力、胶黏剂配方与配比、环境条件)对无纬布性能(包括表观性能、防弹性能等)的影响,探究出一组最佳的工艺条件。连续化生产制备的单向布通过压机复合压制成层叠产品,做成的靶片进行实弹打靶测试,由单向布织造成的防弹芯片通过美国NIJ0101.06测试标准。证明了此工艺生产的产品性能的优异性,为生产出高品质的芳纶无纬布产品打下坚实的基础。     

芳纶无纬布防刺性能初探

针对目前国内外对芳纶无纬布防刺性能研究较少的情况,以及目前防刺服柔软度较差的事实,从织造芳纶无纬布的水性胶粘剂的胶膜本身耐穿刺性能入手,并对无纬布进行后期处理,开创性地将芳纶无纬布应用于防刺领域。确定水性胶粘剂C具有一定硬度并且与芳纶纤维匹配较好,为防刺用芳纶无纬布的胶粘剂配方;经过后期处理后,通过准静态穿刺性能测定不同胶含量的单层无纬布刺穿力,确定树脂含量为24%～27%时,芳纶无纬布具有最优的刺穿力,此时无纬布面密度为225 g/m~2;通过动态穿刺性能测试确定,将芳纶无纬布叠加至34层(单层面密度为225 g/m~2),加一层4.5 mm厚EVA泡沫(面密度为200 g/m~2)作为缓冲层,其防刺性能在-20℃～55℃范围内均满足GA 68—2008标准的测试要求,此时防护层面密度(含缓冲层)仅为7.85 kg/m~2,且具有较高的柔软度,可任意角度折叠180°。     

芳纶无纬布的制备及其抗弹性能研究

优化了芳纶无纬布的制备工艺,根据弹丸对芳纶无纬布层压板的冲击试验结果,对芳纶无纬布层压板的抗弹机理以及不同芳纶织物结构的抗弹性能进行了研究,同时研究了面密度对无纬布抗弹性能的影响。结果表明:无纬布相对于其它织物结构具有较优的抗弹性能,当无纬布具有较低的面密度时,其层压板的抗弹性能也较好。     

芳纶防弹无纬布热熔胶粘剂的研发

对芳纶防弹无纬布用热熔胶进行筛选,优选了橡胶弹性体类胶粘剂作为芳纶防弹无纬布生产用热熔胶,并对该类热熔胶粘剂与传统的丙烯酸酯胶粘剂和聚氨酯胶粘剂在常温、高低温、浸水和耐老化条件下进行了对比试验,结果表明,该热熔胶粘剂中SIS-Kraton D1107胶粘剂防弹等综合性能均明显优于其它胶粘剂,可以作为芳纶防弹无纬布生产用胶粘剂。     

树脂对芳纶无纬布防弹防刺性能的影响

采用树脂与芳纶无纬布模压的方法,制备了一种具备防弹防刺功能的复合材料,讨论了模压温度、时间、压力等因素对其性能的影响。实验结果表明,以树脂和芳纶无纬布为原料制备的防弹防刺复合材料,其工艺优化条件为：模压时间15～30min,温度125℃,压力2～4MPa。在此条件下,制得的复合材料的防弹防刺综合性能最佳。     

芳纶压板无纬布纤维脱粘问题改进研究

通过红外测试及不同相对湿度下的实验对比,确定了芳纶(对位芳纶)压板无纬布纤维脱粘问题的影响因素。对树脂进行共混改性实验,改善了树脂与纤维的界面相容性,增强了树脂对纤维的粘接性能,并确定改性剂最佳质量分数为26%;为改善树脂对相对湿度的敏感性,对溶剂进行了相应调整;解决了织布过程中脱粘问题,提高了压板无纬布产品的质量。     

芳纶无纬布产品研究进展

综述了国内外芳纶无纬布制备技术的发展及其原材料芳纶的技术状态,包括美国、日本、欧洲等国家已经产业化的对位芳纶产品的种类,在全球实现商业化生产的间位芳纶和杂环芳纶的生产线情况以及我国逐渐兴起的芳纶生产线技术等。分析了采用芳纶无纬布制备的防弹产品,为抵御不同防弹级别在单层及复合结构上的设计特点,探讨了新一代芳纶无纬布产品采用的新技术与应用的新领域,以及其在功能上的集成与革新,展望了未来芳纶无纬布相关技术的发展趋势。     

芳纶机织布混杂芳纶无纬布的防弹性能研究

通过采用不同芳纶机织布组合芳纶无纬布进行实弹打靶测试确定,在控制凹陷方面,CT709相对CT714优势较大;通过机织布放置在不同位置进行实弹打靶测试确定,机织布放置在最前面的防弹效果优于机织布放置在中间的位置;最终确定了4层CT709+21层防弹芳纶无纬布的防弹结构,此结构能抵御NIJ0101.06中ⅢA级别子弹的冲击...     

芳纶防弹板的研制

以改性丁苯橡胶为基体,以Kevlar(芳纶)织物及无纬布为增强材料,制备了芳纶防弹板。研究了基体和织物结构对Kevlar防弹板抗弹性能的影响,并讨论了弹道冲击破坏机理及V_(50)的表达式。     

芳纶防弹材料阻燃性能的开发

本课题根据机理分析与对比,优选了一种适用于水性聚氨酯的含磷阻燃剂,并以不同含量的阻燃剂改性胶黏剂体系,制备胶膜与芳纶无纬布,测试力学性能、耐水性及氧指数。结果表明,当含磷阻燃剂A添加量为15%时,改性树脂力学性能得到提升,以其制备的芳纶无纬布的氧指数达到最大值35%,研制出了一种本质阻燃的芳纶无纬布产品,可用于阻燃型防弹产品的生产。     

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。