环硼氮烷的研究进展

对环硼氮烷的合成、结构和反应进行了综述。环硼氮烷可由氨或铵盐与氯化硼合成。经单晶 X射线衍射分析证实其分子中存在共轭π键 ,其结构与苯相似 ,因而具有相似的物理性质 ,但因分子中硼和氮原子的电负性不同 ,它显示高度的反应活性 ,最典型的是同氯化氢发生加成反应。环硼氮烷在化学中被称之“无机苯”,在应用基础研究中已合成了氮化硼薄膜[1] ,它在替代有机物合成薄膜等材料中具有广泛的应用价值     

Si-C-N陶瓷前驱体聚硅氮烷合成的研究进展

综述了合成Si—C—N陶瓷前驱体聚硅氮烷的主要方法，即氨／Q解氯硅烷法、硅氮烷低聚物交联法、硅氮烷低聚物与氯硅烷反应法及氯硅氯烷和氯硅烷脱氯编聚法，并介绍了用铝、硼、钛、钇等元素对聚硅氮烷进行改性，以提高Si—C—N陶瓷性能的方法。     

氮化硼的制备及其性能表征

以三氯化硼和氯化铵为原料,在110℃合成三氯环硼氮烷(TCB),将合成的TCB与异丙胺在0℃左右进行胺解反应,将胺解产物在120℃聚合,得到聚硼氮烷高聚物,聚硼氮烷经1 000℃氮化得到氮化硼(BN),对BN的热性能及晶体结构等进行表征。结果表明:通过红外光谱和X射线衍射分析,聚合产物为聚硼氮烷,经1 000℃氮化后,形成BN晶体,晶体结构为斜方晶系;氮化过程存在部分游离碳(C),BN晶体中含有B,N,C元素;聚硼氮烷可溶于二甲基亚砜和N,N-二甲基甲酰胺,可以进行湿法纺丝。     

三氯环硼氮烷及其衍生物的制备与表征

以三氯化硼和氯化铵为原料,以氯苯为溶剂,采用Schlenk技术合成并提纯出高纯度三氯环硼氮烷(TCB)晶体,利用二甲胺与TCB进行反应,得到TCB的衍生物烷基胺环硼氮烷,为获得高质量BN材料作了原料准备. 采用NMR以及单晶衍射方法对合成样品进行了分析,对反应条件、反应装置及反应路线进行了考察. 研究结果表明,合成反应为均液相反应,加入催化剂Hg, TCB产率可达89%以上;不加催化剂,适当延长反应时间,TCB产率可达87%以上. 在提纯TCB的步骤中,精馏塔理论塔板数为6时较佳. 采用B3LYP/6-31G*计算水平对取代反应过程进行模拟计算,结果表明,取代反应过渡态包含Cl-B-N-HCl四元环结构,通过计算推测反应有可能生成几种取代衍生物的混合物.     

杂原子分子筛ZrBSrALPO4—5的合成结构及催化性能的研究

我们用热水合成法合成了一种锆-硼-硅磷铝分子筛，通过化学分析，测定晶胞参数及用XRD，MAS NMR方法进行表征，证实了锆-硼-硅原子进入了分子筛骨架，并且具有和AIPOR-5相似的结构；用IR，NH3-TPD表征方法测出了它们的酸性，测定结果表明，它具有L-酸性，测定结果表明，它具有L-酸和B-酸中心，以中等强度酸为主，在苯与烯烃烷基化反应中表现出良好的催化活性和长寿命并且对2-位和3-位苯的烷基化反应具有高选择性，有可能替代HF成为一种环境友好的新型催化剂。     

SiBNC陶瓷纤维前驱体-聚硅硼氮烷的合成与表征

以四氯化硅、三氯化硼、甲胺为原料,使用共缩聚方法制备了SiBNC陶瓷纤维前驱体聚硅硼氮烷。采用FT-IR、NMR、GC-MS和TG分析等,对聚硅硼氮烷的结构、性能和合成机理进行了表征和分析。研究表明该聚硅硼氮烷前驱体的骨架结构由Si-N-B和B-N六元环结构组成,C则主要以N-CH_3和NH-CH_3结构存在。合成得到的前驱体具有良好的溶解性、耐水解性能和可纺性,在105℃的N_2气氛下,经熔融纺丝可得直径约为25μm的前驱体原丝,在N_2气氛中1 000℃时陶瓷产率为60%。     

SiBCN陶瓷先驱体的制备和应用研究进展

综述了SiBCN陶瓷前驱体制备过程中在硅氮烷上引入硼元素的3种方法(采用环硼氮烷引入硼元素、采用硼氢化反应引入硼元素、采用BCl3引入硼元素);介绍了SiBCN陶瓷前驱体在制备介孔骨架、涂覆碳纳米管、制备无定形涂层上的应用;以及先驱体转化的SiBCN陶瓷的结晶化过程及陶瓷结构分析(无定形SiBCN陶瓷的结晶化过程,不同SiBCN陶瓷前驱体生成的陶瓷结构的对比)。     

杂原子分子筛ZrBSiAlPO4-5上长链烯烃与苯的烷基化的研究

合成了一种锆－硼、硅磷铝分子筛，它具有和AlPO4-5相似的结构，用XRD，IR，NH3－TPD等方法作了表征，酸性的测量表明，它具有L－酸和B－酸中心，以中等强度酸为主，在苯与烯烃烷基化反应中表现出良好的催化活性和长寿命，讨论了催化剂的酸性与烷基化反应活性的关系，有可能替代HF成为一种环境友好的新型催化剂。     

POD基炭薄膜形成过程的研究

制备出了ＰＯＤ（聚恶二唑）薄膜，测定了ＰＯＤ薄膜试样在热解炭化期间的化学结构和重量变化，研究了ＰＯＤ薄膜的炭行为。随着热解温度的提高，ＰＯＤ大分子在氧二氮茂环处发生断裂，形成具有共轭腈基苯的化合物。新生成的〉Ｃ＝Ｎ－和－Ｎ＝Ｃ＝Ｏ基团继续进行反应，其中－Ｎ＝Ｃ＝Ｏ基团通过耦合反应生成炭化二亚胺（－Ｎ＝Ｃ＝Ｎ－）；再经分子链环化转变成具有吡啶型大共轭结构的多环化合物，继而稠环芳构化生成类石墨芳香族六     

胺改性硼酚醛树脂的研究

本文研究了甲醛水溶液法合成胺改性硼酚醛树脂的工艺过程及其固化反应机理。结果表明，在合成与固化过程中除生成硼酸酯外还有硼氧配位结构形成；当加入胺后可生成硼酰胺键和硼氮四元环配位结构。由于硼氧，硼氮配位结构的形成提高了树脂的耐水性和耐热氧化能力。     

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。