酚醛纤维及其性能的研究

综述了酚醛纤维在国内外的研究状况;分析了酚醛纤维的制备工艺及固化方法;阐述了酚醛纤维的主要性能及应用,包括阻燃、耐烧蚀隔热、耐腐蚀及酚醛基碳纤维以及酚醛基活性炭纤维前体;指出各种高性能、功能化酚醛纤维、酚醛基碳纤维以及酚醛基活性炭纤维将是未来研究开发的重点。     

一种烧蚀性高温隔热涂料的防腐蚀性能探讨

用有机硅、丙烯酸树脂、环氧树脂和功能颜填料配制了一种烧蚀性隔热防腐蚀涂料,进行高温隔热性能及防腐蚀性能检测,探讨了烧蚀性隔热涂料在未经受高温冲击时涂层的防腐蚀性能(耐湿热和耐盐雾性能等)和在不同的高温下,烧蚀性隔热涂料的保温隔热性能,以及防腐蚀性能与耐高温隔热性能间的协调关系。     

复合材料应用于空间固体火箭发动机

本文介绍了我国近几年来多次发射成功的国产地球同步通信广播卫星、气象卫星的远地点固体火箭发动机及近地点固体火箭发动机所用的各种复合材料部件的研制、试验和使用情况。所用的复合材料包括高强度纤维缠绕成型的燃烧室壳体、高性能碳/碳复合材料制造的喷管喉部镶嵌内衬(喉衬)、耐烧蚀橡胶基柔性内绝热层、模压与布带缠绕的刚性喷管隔热件等.重点介绍壳体和喷管材料。 对有关材料的成型工艺、制品性能、使用效果作了叙述.并评述了这些复合材料的发展趋势。     

含硼烯丙基树脂改性BMI树脂

采用 同主链结构的含硼烯丙基树脂改性双马来酰亚胺（ＢＭＩ）树脂，并对其预聚工艺、反应性、固化树脂力学性能、耐烧蚀性能及玻璃布层压性能进行了研究。     

热熔胶膜法制备硅硼改性酚醛树脂预浸料及复合材料

纤维增强酚醛树脂基复合材料具有易成型、加工周期短和隔热性能好等优点,可用作烧蚀型热防护材料。本文对热熔胶膜法制备的高硅氧/硅硼改性酚醛预浸料及其复合材料进行了研究。硅硼改性酚醛树脂具有优异的热稳定性,氮气气氛下,800℃残碳率高达75.3%。高硅氧/硅硼改性酚醛预浸料的百分流动度、挥发份和树脂含量分别为21.3%、5.7%和40.2%。对比溶液法制备预浸料成型的层压板,采用热熔胶膜法制备的高硅氧/硅硼改性酚醛复合材料层压板的弯曲强度和层间剪切强度分别提高了56.2%和22.1%。氧乙炔线烧蚀率和质量烧蚀率分别为0.0498mm/s和0.0506g/s。高硅氧/硅硼改性酚醛复合材料优异的耐烧蚀性能有助于降低热防护材料的厚度,减轻火箭、导弹等的总体质量,对提高武器装备的性能具有重要的意义。     

复合材料带缠绕张力参数对碳/酚醛材料层间剪切强度影响研究

目前缠绕工艺参数对制品层间剪切强度的影响研究多集中于3k碳布或高硅氧布为增强体的复合材料,而一体化复合材料喷管制品烧蚀层常采用1k碳布/酚醛材料进行制备。因3k碳布和1k碳布稀疏特性存在本质区别,将影响酚醛树脂固化过程中产生小分子挥发物的排出效率,从而导致制品性能存在差异。为揭示带缠绕张力对1k碳布/酚醛制品层间性能的影响,采用湿法预浸工艺制备1k碳布/酚醛预浸带,基于控制变量法设计缠绕参数,通过数控布带缠绕机缠绕试样环,设计层间剪切测试工装,实现对试样整环的层间剪切强度测试。结果表明,选用张力系数为20N/cm制备的试样环性能最低,平均值为16.996Mpa;张力系数在30N/cm至70N/cm范围内,制品层间剪切强度波动较为平缓,无明显变化趋势。     

酚醛改性苯并(噁)嗪树脂耐烧蚀材料的研究

对不同组成苯并口恶嗪/酚醛共混树脂体系进行了研究,内容包括共混树脂的反应动力学参数计算、共固化机理、热分解动力学以及耐烧蚀性能等。结果表明:酚醛与苯并口恶嗪树脂共混后可以改变苯并口恶嗪的固化机理,酚醛树脂的加入使口恶嗪分子由热开环变为活泼氢开环,在较低温度下就可以反应,降低了固化反应温度。同时共混树脂可以使固化过程收缩率和小分子挥发物比传统的酚醛树脂低,可以减少烧蚀试样的表面裂纹,致密的碳化层具有一定附着强度,提高了共混树脂烧蚀性能。该共混体系可以作为宇航领域中1种性能优良的耐烧蚀树脂体系。     

专用阻燃涂料配方设计（Ⅱ）

５．１．２ 技术指标 电缆隔热带用阻燃涂料有特定的产品技术要求和使用性能（见表４），以确保达到阻燃防火的目的。５．１．３ 产品特性、施工及应用 　产品特性：涂有阻燃防火涂料的电缆隔热带主要特点是在防刀割的电缆绝缘层外面缠绕上阻燃防火隔热带，在最外面再加上ＰＶＣ防火保护套，制成既防刀割又防窃电的电缆。 　施工要点：将阻燃涂料在涂布机上连续涂覆玻璃布，达到要求后进行烘烤固化，然后切成规范的卷材。 　应用范围：主要用于输电电缆上，作为防刀割、防窃电的阻燃防火电缆，该电缆产品已正式经销。５．２ 电感器用阻燃涂…     

酚醛短切纤维对EPDM绝热材料性能的影响

采用酚醛短切纤维为耐烧蚀填料制备了三元乙丙橡胶(EPDM)绝热材料,探究了酚醛短切纤维长度及含量对EPDM绝热材料耐烧蚀和力学性能的影响。当3 mm酚醛短切纤维的填充量为10份时,酚醛短切纤维填充的EPDM热防护材料综合性能较优,其线烧蚀率为0.098 1 mm/s、拉伸强度为14.6 MPa、断裂伸长率为541%;且扫描电镜观察显示,绝热材料烧蚀后形成的炭层中酚醛短切纤维的形貌保持良好,对炭层起到了较好的骨架支撑作用。     

防热涂层的应用研究

采用双层结构的组合式涂层,可以解决防热涂层的耐烧蚀和隔热的双重问题。叙述了结构方案的选择,烧蚀及隔热涂层的配方以及试验和应用情况。     

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。