用TMPTA改善过氧化物硫化EPDM性能的研究

在ＥＰＤＭ／白炭黑胶料的过氧化物硫化体系中,加入三羟甲基丙烷三丙烯酸酯（ＴＭＰＴＡ）能够迅速提高硫化胶的交联效率,增大网络密度,缩短硫化时间;当ＴＭＰＴＡ用量为０．５份时,ＥＰＤＭ硫化胶的拉伸强度保持率和扯断伸长率保持率达到最大值;在２．０份过氧化二异丙苯（ＤＣＰ）中加入０．５份ＴＭＰＴＡ,胶料的硫化时间比单独使用３．０份ＤＣＰ缩短４０％,且硫化胶的定伸应力、拉伸强度和撕裂强度均明显提高。     

望远镜橡塑装饰包皮的研制

介绍了望远镜橡塑装饰包皮的胶料配方设计、生产工艺和产品性能。望远镜橡塑装饰包皮胶料的主体材料采用ＮＢＲ／ＰＶＣ（并用比８３／１７）并用体系;硫化体系由硫黄（１－２５ 份） 和促进剂ＴＭＴＤ（０－２９ 份）、促进剂ＤＭ（０－４２ 份）、促进剂Ｍ（０－４２ 份）组成;增塑剂选用增塑剂ＤＢＰ（８－３ 份）;黑色胶料的防老剂选用防老剂２２４６（１－６ 份）,非黑色胶料的防老剂选用防老剂２６４（２－０ 份）;黑色胶料的补强填充剂选用ＨＡＦ／ＧＰＦ（并用比８３／１７） 并用体系,非黑色胶料的补强填充剂选用白炭黑／ 陶土（ 并用比７５／１７）并用体系。ＮＢＲ 的塑炼采用低温、小辊距和低容量的三段塑炼法;ＮＢＲ与ＰＶＣ的共混采用常温共混工艺;混炼胶的威氏塑性值控制在０－２８～０－３０ 之间;制品在平板硫化机上硫化完毕后,再在１６０～１７０ ℃的烘箱中热处理１５～３０ ｍｉｎ。胶料物理性能良好,成品性能满足设计要求。     

耐辐射无卤阻燃绝缘EPDM电缆胶料的研究

本研究耐辐射无卤阻燃绝缘ＥＰＤＭ电缆胶料的主要配合为：生胶为乙烯含量较高的１，４－己二烯型电绝缘级ＥＰＤＭ（１００份）；阻燃剂为氢氧化铝／氢氧化镁／三氧化二锑并用体系（９５～１００份），其中氢氧化铝和氢氧化镁用硬脂酸锌进行表面处理；补强填充剂为煅烧陶土、ＬＥＥ白滑粉、ＰＹ－Ⅱ型水白云母粉和钛白粉并用体系（１０５～１１５份）；硫化剂为２，５－二甲基－２，５－二（叔丁基过氧化）己烷（４～５份），共硫化剂为三羟甲基丙烷三甲基丙烯酸酯和Ｎ，Ｎ′－间亚苯基双马来酰亚胺并用体系（１．６～１．８份）。胶料和成品的物理机械性能、介电性能、阻燃性能和耐环境性能（耐热性、耐蒸汽性和耐辐射性）达到ＩＥＣ５０２（１９９４）和ＩＥＣ１８Ａ（１９８１）（ＣＯ）标准。     

低损耗阻燃高电压EPDM绝缘胶料的开发

在低损耗阻燃高电压ＥＰＤＭ绝缘胶料的配方中,阻燃剂选择由硅烷偶联剂和硬酯酸锌联合处理的１８０目的氢氧化铝和氢氧化镁,用量分别为４０～７０和２０～４０份,硫化助剂选择三（甲基丙烯酸三羟甲基）丙烯酸酯,用量为１．５～２．５份;软化体系采用超低门尼粘度的ＥＰＤＭＫｅｌｔａｎ１４４６Ａ与微晶蜡并用,绝缘胶料的性能符合ＩＥＣ５０２—１９９４的要求,并具有低的电损耗和耐高电压性能。     

无内胎轮胎气密层胶料硫化体系的优化设计

氯化丁基橡胶（ＣＩＩＲ）／天然橡胶（ＮＲ）并用胶料采用烷基苯酚二硫化物（ＡＰＤ）（Ａｕｌｔａｃ５）／秋兰姆（ＴＭＴＤ）／噻唑（ＤＭ）并用体系代替常规的硫黄体系和低硫／秋兰姆／噻唑并用体系硫化，运用正交中心复合试验方法进行配方试验。利用计算机绘制胶料物理性能等值图，对胶料物理性能进行讨论，优选出Ｖｕｌｔａｃ５、促进剂ＴＭＴＤ、促进剂ＤＭ等的最佳用量，从而获得与常规硫化体系胶料配方相比加工安全性好、硫     

辐射硫化耐高电压乙丙橡胶绝缘料的开发

开发了辐射硫化低损耗耐高电压乙丙橡胶绝缘料。试验发现：辐射硫化的敏化剂宜选择三（甲基丙烯酸三羟甲基）丙烷酯,用量为１．５－２．５（质量份）;增塑剂宜采用超低门尼粘度的ＥＰＤＭＫｅｌｔａｎ １４４６Ａ与微晶石蜡并用,绝缘橡胶的性能符合ＩＥＣ５０２－１９９４年的要求。     

丁腈橡胶与金属扯离强度的影响因素

介绍了硫化体系、胶粘剂及无机填料等因素对丁腈橡胶（ＮＢＲ）与金属扯离强度的影响。硫化剂ＤＴ－ＤＭ对ＮＢＲ与金属扯离强度会产生不利影响，并随其用量增加，这种影响加剧。试验得出：ＮＢＲ胶料硫化体系选用硫黄０．５、促进剂ＴＭＴＤ１．５、硫化剂ＤＴＤＭ１．０、促进剂ＣＺ１．０，无机填料选用轻质氧化镁１５，而胶粘剂选用胶粘剂ＲＭ－１（预固化条件１４０℃×１５～２０ｍｉｎ），胶料与金属的扯度强度和附胶情况良好     

辐射硫化耐高电压乙炳橡胶绝缘料的开发

开发了辐射硫化低损耗耐高电压乙丙橡胶绝缘料。试验发现：辐射硫化的敏化剂宜选择三（甲基丙烯酸三羟甲基）丙烷酯,用量为１５～２５（质量份）;增塑剂宜采用超低门尼粘度的ＥＰＤＭＫｅｌｔａｎ１４４６Ａ与微晶石蜡并用,绝缘橡胶的性能符合ＩＥＣ５０２－１９９４的要求     

吉尔130汽车发动机供油系统O形密封圈的研制

含有活性添加剂的Ｍ－８＿Ｂ１和Ｍ－８＿Ｔ２Ｋ的两种油品对ＮＢＲ－１８Ｏ形密封圈有一定的副作用，通过调整ＮＢＲ胶料硫化体系（硫黄０．３；促进剂ＣＺ１．５；促进剂Ｍ０．５；硫化剂ＤＣＰ２．０）和补强剂炭黑的用量（高耐磨炭黑５５；喷雾炭黑４０）．可以使其满足抗两种油品侵蚀的性能要求。另外，在ＮＢＲ胶料中添加２５份耐寒增塑剂（邻苯二甲酸二丁酯１０；癸二酸二辛酯１５）．可提高胶料的耐低温性能，并使脆性温度降至－６５℃以下。     

氢氧化镁填充的VAMAC无卤低烟阻燃电缆胶料的配方与性能

在乙烯－丙烯酸酯橡胶（ＶＡＭＡＣ）无卤低烟阻燃电缆胶料配合中，主要填料氢氧化镁及其表面处理剂硬脂酸锌的用量是关键，硫化体系也较重要。胶料优化配方为：ＶＡＭＡＣ１００；２，５－二甲基－２，５－双（叔丁基过氧）己烷３．０～３．３；Ｎ，Ｎ′－间亚苯基双马来酰亚胺和三（甲基丙烯酸三羟甲基）丙酯０．８～１．０。硬脂酸锌处理过的陶土＋ＬＥＥ白滑粉５０～６０；加工助剂１２～１４；硬脂酸锌１．２～１．４；氢氧化镁４３～４７；其它６～７。胶料阻燃、低烟和物理机械性能良好，成品电缆通过ＧＢ１２６６６—９０燃烧试验，且完全满足设计和ＩＥＣ５０２（１９９４）性能要求     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.