N_2O_5硝解DPT制备HMX

为了获得绿色硝化DPT制备HMX的工艺,研究了N2O5/HNO3和N2O5/有机溶剂两种硝化体系硝解DPT.在N2O5/有机溶剂体系中考察了不同溶剂对DPT的硝解,主要生成了低熔点的副产物,只有极少量的HMX生成,N2O5/有机溶剂体系不适合硝解DPT制备HMX.在N2O5/HNO3体系中硝解DPT,考察了反应时间、反应温度、硝酸铵用量、反应料比等对HMX收率的影响.结果表明,随着N2O5用量的增加,HMX的收率呈现先增加后降低,在N2O5与DPT物质的量比为2、HNO3与DPT的物质的量比为36、反应时间30 min、反应温度25℃的条件下,HMX收率可达58%,纯度99%,得出在N2O5/HNO3体系中硝解DPT能以较高收率制备HMX.     

N_2O_5/HNO_3硝解合成TEX工艺研究

以N2O5/HNO3为硝解剂、4种取代哌嗪为底物,制备了4,10-二硝基-2,6,8,12-四氧杂-4,10-二氮杂四环[5.5.0.05.903.11]十二烷(TEX),优化了目标产物的合成工艺;探讨了表面活性剂、酸性离子液体等催化剂对反应收率及纯度的影响。结果表明,以1,4-二甲酰基-2,3,5,6-四羟基哌嗪(DFTHP)作为硝解底物,加料温度为40℃,反应温度为75℃,反应时间为40min,加料比m(DFTHP)∶m(N2O5)∶V(HNO3)为2g∶1g∶20mL时,TEX收率达45.6%,纯度达95.6%。当以十六烷基三甲基溴化铵(CTAB)、离子液体[Et3N(CH2)4SO3H][HSO4]和CF3SO3H/树脂(质量比为1∶9)为催化剂时,TEX收率可进一步提高3%~14%。     

N2O5硝解三丙酰基三氮杂环己烷制备RDX

以三丙酰基三氮杂环己烷为原料,N2O5/HNO3为硝解剂制备了RDX.分别考察了硝解剂浓度、反应物配比、反应温度和反应时间对RDX产率的影响.结果表明,当N2O5与HNO3的摩尔比为1∶10,N2O5与三丙酰基三氮杂环己烷的摩尔比为6∶1,反应温度为45℃,反应1 h,RDX的最高产率可达92.7%,纯度为98.5%.     

N_2O_5/HNO_3硝解TAIW合成CL-20

以2,6,8,12-四乙酰基-2,4,6,8,10,12-六氮杂四环-[5,5,0,03,11,05,9]十二烷(TAIW)为原料,采用N2O5/HNO3为硝化剂硝解TAIW制备六硝基六氮杂异伍茲烷(CL-20)。通过系统研究N2O5/HNO3硝解TAIW的加料方式、温度、料比、反应时间、稀释用水量等因素对反应收率和纯度的影响,找出了最佳反应条件:反应温度60~80℃,反应时间7h,m(TAIW)∶m(N2O5)∶V(HNO3)=3g∶4g∶15mL,后处理时稀释用水量20mL,CL-20收率为82.34%,纯度为98.29%。当以质量分数10%的CF3SO3H/树脂为催化剂时,收率提高至87.35%,纯度基本不变,且催化剂的回收率达到99.15%。该方法避免硫酸的使用,减轻了废酸污染,具有较强的工业化应用前景。     

超声波协同Fenton氧化法预处理HMX生产废水的实验研究

采用超声波协同Fenton氧化技术对HMX生产废水进行处理,考察了超声波频率及功率、Fenton试剂的投料量、废水的pH值、反应初始温度等参数对HMX生产废水中污染物降解的影响。结果表明,反应初始温度及废水的pH值对降解结果的影响较大。在超声波频率为45Hz、功率为5kW/m3、H2O2与Fe2+投料量分别为0.235mol和0.023mol,即n(H2O2)∶n(Fe2+)=10∶1,反应初始温度30℃条件下,100mL HMX废水的COD去除率达到80%以上;在H2O2投料量较少时超声波协同效应的优势明显,H2O2与Fe2+摩尔比越低,超声波协同效应越显著,比单独使用Fenton试剂处理的效果好;当H2O2与Fe2+摩尔比高于10∶1时,超声波的协同效应几乎消失。     

AIL-N2O5-HNO3体系中硝解DADN制备HMX

在酸性离子液体(AIL)催化下利用N2Os硝解DADN制备了HMX.考察了离子液体用量、反应时间、物料配比、不同离子液体对硝解反应的影响,在优化条件下进行了对比试验.结果表明,在所用的21种AIL中,[Et3NH]TsO具有最好的催化效果,HMX的纯度为99％,收率可达到95.6％,离子液体可以通过简单的萃取后回收使用...     

2,5-二氯硝基苯新生产工艺

确定了以对二氯苯为原料,N2O5/HNO3为硝化剂,合成2,5-二氯硝基苯的工艺条件:反应温度为55~60℃,N2O5/HNO3质量分数为20%,N2O5/HNO3与对二氯苯的摩尔比为1∶1,反应时间为1 h。在此条件下,产品纯度大于99.5%(质量分数),收率为99%。     

N_2O_5/HNO_3硝解乌洛托品制备RDX的机理

利用13 C NMR谱监测了乌洛托品(HA)在N2O5/HNO3和N2O5/HNO3/CH2Cl2硝化体系中硝解反应的历程,根据实验13 C NMR谱和计算13 C NMR谱的解析结果,并结合HA硝解反应过程中可能存在中间体和副产物的13 CNMR理论计算结果,提出了硝解历程中可能存在的中间体与副产物的结构,推测了HA在N2O5/HNO3体系中的硝解历程为:HA首先与两分子HNO3结合生成乌洛托品二硝酸盐(HADN);HADN再经环三亚甲基硝胺母体逐步降解为黑索今(RDX)。     

硝酸-硝酸铵体系中DPT硝解制备HMX工艺研究

在硝酸-硝酸铵体系硝解3,7-二硝基-1,3,5,7-四氮杂双环[3,3,1]壬烷(DPT),制备HMX,通过正交实验确定最佳工艺条件。结果表明,最佳工艺条件为:10 mL硝酸与3 g硝酸铵配制硝解液,控制5℃下加入0.735 g DPT,保温溶解30 min,升温至25℃,反应40 min,HMX的平均收率为61.2%;各因素对HMX产率的影响顺序为:硝酸铵加入量>DPT加料温度>反应时间>反应温度。采用HPLC离线监测最佳工艺条件下的硝解反应,得到DPT和HMX浓度的变化规律,并对相关反应过程进行了推测。     

Fenton氧化法降解HMX废水中有机物的氧化反应动力学

用Fenton氧化技术研究了降解HMX废水中有机物的工艺及氧化反应动力学。结果表明,适宜的降解工艺条件为:H2O2投加量2mol/L,H2O2与Fe2+摩尔比为40∶1,pH值为3,反应温度20℃,反应时间1.5h。在上述条件下HMX废水的COD去除率为68.5%。在研究的温度范围内,用Fenton氧化法降解HMX废水中有机物的氧化反应为一级反应,反应的活化能和指前因子分别为7.03kJ/mol和0.067 7min-1。     

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。