N,N—二甲基氨基乙醇及其衍生物在聚氨酯反应中的应用

为了考察催化剂结构对性能的影响,研究了 N,N-二甲基氨基乙醇,2-[2-(N,N-二甲基氨基)乙氧基]乙醇、2-{2-[2-(N,N-二甲基氨基)乙氧基]乙氧基}乙醇在硬质聚氨酯泡沫中的应用。发现羟基距氮原子间的距离对催化剂性能影响很大,当羟基和氮原子相距5个原子时,催化剂活性最高,其它次之。三种化合物单独使用时,乳白时间短,凝胶时间长,反应不协调,实际应用中最好和其它催化剂共用。     

新刊导读

医药、兽药N,N-二甲基甲酰胺缩二甲醇对蝶呤的甲基化反应/姚其正//有机化学.-2002,22(8).-555～559 用N,N-二甲基甲酰胺缩二甲醇[(CH3)2NCH(OCH3)2,1]和蝶呤(2-氨基4-羟基蝶啶)衍生物在极性有机溶剂中反应一般得到脒化产物:N2-(N,N-二甲基氨基亚甲基)-蝶呤衍生物。但是在1,4-二氧六环中进行以上反应     

聚[甲基丙烯酸(N,N-二乙基氨基乙酯)]的合成

聚[甲基丙烯酸(N,N-二乙基氨基乙酯)](PDEAEMA)是一种具有p H响应性的聚合物,可以用作稳定剂、纳米凝胶、水凝胶、生物医用材料等。本文利用2-氯丙酸丙炔酯为引发剂,以氯化亚铜和氯化铜为催化剂,引发甲基丙烯酸(N,N-二乙基氨基乙酯)的原子转移自由基聚合(ATRP),合成出聚[甲基丙烯酸(N,N-二乙基氨基乙酯)](PDEAEMA),并用核磁共振氢谱(1H NMR)证实了产物的结构。     

双(2-二甲基氨基乙基)醚的制备及分离

在氮气保护下,加热N,N-二甲基乙醇胺和浓硫酸,使N,N-二甲基乙醇胺分子间脱水得到双(2-二甲基氨基乙基)醚。考察了反应时间、反应温度、浓硫酸的用量对产物收率的影响;最佳反应条件为:200~210℃,4~5 h,物料摩尔投料比为:n(浓硫酸)∶n(N,N-二甲基乙醇胺)=3.0∶1.0。用新型分离装置对反应液进行分离后,经减压精馏得到双(2-二甲基氨基乙基)醚[w(双(2-二甲基氨基乙基)醚≥98%],其收率为55.6%(以N,N-二甲基乙醇胺)。     

一种磺酸型水性聚氨酯扩链剂的合成、表征及应用

以自制的中间体N,N-二(2-羟乙基)-2-氨基丙烯为原料,对其进行磺化反应,控制温度、时间和摩尔比反应合成磺酸型水性聚氨酯扩链剂N,N-二(2-羟乙基)-2-氨基丙磺酸钠,借助核磁氢谱(¹H NMR)、红外光谱(FTIR)、元素分析、X射线衍射(XRD)等手段对合成产物进行了组成、结构和结晶性表征,用热重分析仪表征了产物的热稳定性。根据产物的磺化度确定最佳的合成工艺:反应温度为90℃,反应时间为8 h,N,N-二(2-羟乙基)-2-氨基丙烯和亚硫酸氢钠(NaHSO₃)的物料比为1:2.5,磺化率可达到94%以上。分别以二羟甲基丙酸(DMPA)和自制磺酸型单体作为亲水扩链剂制备羧酸型水性聚氨酯(CWPU)和磺酸型水性聚氨酯(SWPU),其性能对比结果表明:SWPU相比于CWPU具有较好的亲水性和耐热性能;固含量及稳定性方面,SWPU也是优于CWPU的。     

萘酚萘磺酸酯的合成研究

在N,N二甲基乙酰胺存在下,通过7-乙酰氨基-4-羟基-2-萘磺酸钠与三氯氧磷在乙腈中反应,合成7-乙酰氨基-4-羟基-2-萘磺酰氯。同时对三氯氧磷、N,N二甲基乙酰胺、乙腈与7-乙酰氨基-4-羟基-2-萘磺酸钠的投料比进行了考察,发现较优的投料物质的量比为3：4：30：1,在此条件下产物的收率可达90％。该工艺节省了大量溶剂环丁砜,而且重复性好。制备的磺酰氯与N,N-二甲基乙二胺,以碳酸钾做缚酸剂,在乙腈中通过缩合反应合成了萘酚萘磺酸酯。合成化合物的结构通过^1H和^13C核磁共振谱、质谱、红外光谱分析得以表征。     

对二氯苯和N-甲基-4-氨基丁酸钠的反应动力学

为了探究对二氯苯(DCB)与N-甲基-4-氨基丁酸钠(SMAB)的反应对聚苯硫醚(PPS)聚合反应的影响,采用动力学方法研究PPS聚合条件下DCB与SMAB的反应。通过分析反应网络、简化反应过程,建立产物N,N′-二甲基-N,N′-(1,4-亚苯基)-4,4′-二氨基二丁酸钠、N,N′-二甲基-N,N′-(1,3-亚苯基)-4,4′-二氨基二丁酸钠(均记为d-SPMAB)、N-甲基-N-(3-氯苯基)-4-氨基丁酸钠(m-SCMAB)、N-甲基-N-(4-氯苯基)-4-氨基丁酸钠(p-SCMAB)和对氯苯酚钠(p-SCP)的生成反应动力学模型;根据质量作用定律、采用稳态假设,推导出各产物的生成反应动力学方程,并运用实验数据进行线性拟合。结果表明：产物d-SPMAB、m-SCMAB、p-SCMAB和p-SCP的生成反应表观活化能分别为168.8、154.5、120.3和131.6 kJ·mol^-1;增大SMAB与DCB物质的量比可以加快反应,但不改变反应机理;水有利于DCB的水解反应,但溶剂化作用会阻碍DCB与SMAB的取代反应。     

双组分Iniferter引发苯乙烯聚合的研究

研究了由N,N-二乙基二硫代氨基甲酸苄酯(BDC)与四甲基秋兰姆化二硫(TMTD)组成的复合Iniferter(引发剂-转移-终止剂)引发苯乙烯的光聚合反应。     

雄激素受体拮抗剂MDV3100的合成研究

以3-三氟甲基-4-腈基-苯胺和二硫化碳为原料制备异硫氰酸酯4-异硫氰基-2-三氟甲基苯腈(2),以2-氟-4-硝基甲苯为原料,经氧化、酰胺化、催化氢化制得N-甲基-2-氟-4-氨基苯甲酰胺(5),5与2-溴异丁酸乙酯反应得到2-(3-氟-4-甲胺甲酰苯基)胺基苯胺-2-甲基丙酸乙酯(6),2和6在无水N,N-二甲基甲酰胺溶液中缩合得到MDV3100(1),结构经MS和1H NMR确证,总收率18%(以2-氟-4-硝基苯甲酸计,n/n)。     

N,N-二取代氨基苯甲醛的合成

通过N,N-二取代苯胺的酰基化反应,以高收率合成了三种用于制备腙类空穴传输材料的重要中间体,2-甲基-4-(N,N-二苄基)氨基苯甲醛、2-甲基-4-(N-乙基-N-苄基)氨基苯甲醛和4-(N-乙基-N-苄基)氨基苯甲醛,收率分别达99.2%、92.9%和94.8%,高效液相色谱纯度99.2%以上。通过官能团鉴定、紫外吸收光谱、红外吸收光谱、质谱以及元素分析等对产物的组成和结构进行了鉴定。     

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。