线形无规共聚物SIBR的合成与表征

采用阴离子聚合法合成了苯乙烯-异戊二烯-丁二烯无规共聚物(SIBR),并通过1HNMR分析对产物序列结构进行了表征.实验证明,控制聚合温度在50～70℃,n(THF)∶n(Li)在(9～25)∶1之间或n(THF)∶n(Li)为7.0∶1且2G与Li摩尔比在0.08～0.45之间或2G与Li的摩尔比在0.10～0.35之间可调节1,2-PB与PB摩尔比在21%～32%之间、3,4-PI与PI摩尔比在39%～52%之间变化且苯乙烯单元在聚合物链上呈无规分布.     

星型SIBR合成中偶联反应的研究

以n-BuLi为引发剂,环乙烷为溶剂,SnCI4为偶联剂,在不同极性添加剂存在下合成了苯乙烯、异戊二烯和丁二烯的偶联星型无规共聚物SIBR。研究了聚合阶段不同极性添加剂（THF、THF－2G和2G)、偶联温度、偶联剂用量及偶联方式对偶联效果的影响。 研究结果表明适宜的工艺条件为：极性添加剂THF或THF－2G;偶联温度70℃;偶联剂用量n(SnCI4)/n(Li)=0.40-0.45(THF作极性添加剂）或0．35（THF－2G作极性添加剂）;二次偶联、偶联前加入适量极性添加剂及丁二烯戴帽,都可以提高偶联效果。     

四氢呋喃/叔丁基氧钾双组分调节剂在溶聚丁苯橡胶合成中的作用

以n- BuLi为引发剂,环已烷为溶剂,四氢呋喃(THF)为结构调节剂,THF和叔丁基氧钾(t - BuOK)为无规化剂,在聚合温度为50℃时进行苯乙烯与丁二烯的二元共聚,考察了t- BuOK/n - BuLi(摩尔比)对共聚物结构的影响.结果表明,在THF/n - BuLi(摩尔比)控制为50的条件下,当t - Bu...     

星形杂臂异戊二烯-丁二烯共聚橡胶的合成与表征

以环己烷为溶剂、正丁基锂(n-BuLi)为引发剂、四氢呋喃(THF)和五甲基二乙基三胺(PMDETA)为微观结构调节剂、二乙烯基苯(DVB)为偶联剂,采用"臂先"和"核先"相结合的方法合成了星形杂臂异戊二烯-丁二烯共聚橡胶[S-(PI)n-(PB)n],并对其结构进行了表征。结果表明,最佳聚合工艺条件为单体质量浓度0.1 g/mL、温度50~60℃、异戊二烯(Ip)聚合时间1 h;在偶联反应时间为1 h、[DVB]/[Li](摩尔比)为1.0、聚异戊二烯的单臂数均分子量为6×104~10×104的条件下,采用Ip与DVB(摩尔比5∶1)混合后的加入方式进行偶联反应,偶联效率可达70%,S-(PI)n-(PB)n的数均分子量为2.2×105~4.9×105,分子量分布可控制在1.80~2.10,PI和PB的平均臂数可达3~4,凝胶质量分数低于1.0%;当[THF]/[Li](摩尔比)为0.5、[PMDETA]/[Li](摩尔比)为1.0时,S-(PI)n-(PB)n中乙烯基质量分数可以达到63%。     

对称型双端过渡态丁二烯/苯乙烯嵌段共聚物的研制Ⅰ.共聚合反应动力学研究

以双卤代烷烃取代型双锂齐聚物为引发剂、环己烷为溶剂,丁二烯(B)、苯乙烯(S)单体采用1次加入的方法,合成了对称型双端过渡态丁二烯/苯乙烯嵌段共聚物S-(S/B)-B-(B/S)-S,并对双锂体系丁二烯、苯乙烯共聚合反应过程进行了研究,将丁二烯、苯乙烯共聚合反应动力学数据进行分段处理,求得不同引发温度、不同单体配比、不同极性添加剂用量[二乙二醇二甲醚(2G)/Li]下丁二烯聚合段、苯乙烯聚合段假一级表观增长反应速度常数kp1、kp2;求得不同2G/Li下丁二烯、苯乙烯共聚合反应的表观竞聚率,随着2G/Li的增大,丁二烯的表观竞聚率减小,苯乙烯的表观竞聚率增大,表明随着2G/Li的增大,丁二烯、苯乙烯逐渐向无规共聚合方向发展.     

中石油简讯

1．开发出负离子聚合法高苯乙烯含量橡胶 中国石油兰州化工研究中心研究人员以环己烷为溶剂、苯乙烯和丁二烯为单体、n—BuLi为引发剂、二乙二醇二甲醚（2G1为结构调节剂,通过活性负离子溶液聚合合成高苯乙烯橡胶,研究了引发剂种类、聚合温度、2G／n—BuLi（摩尔比）、苯乙烯／丁二烯f质量比1、相对分子质量及其分布对共聚橡胶力学性能的影响。     

三异丁基铝阻滞苯乙烯负离子聚合动力学

以环己烷为溶剂、三异丁基铝为阻滞剂、丁基锂为引发剂,研究了三异丁基铝与丁基锂摩尔比[n(Al)/n(Li)]和聚合温度对苯乙烯阻滞负离子聚合反应速率和动力学的影响规律,对相应的假一级表观增长速率常数进行了求解.结果表明,采用三异丁基铝/丁基锂体系引发苯乙烯阻滞负离子聚合,在苯乙烯转化率较低(小于60％)时,苯乙烯聚合速...     

一种具有优异光学性能的丁苯共聚物的合成

采用负离子聚合技术,在单体质量浓度为0．20—0．25g／mL,聚合温度为65—80℃时,通过四步聚合反应合成了一种具有较好光学性能的丁苯聚合物,探讨了四氧呋喃（THF）／正丁基锂（简称Li）及混合单体进料时间对产物光学性能的影响。结果表明,当THF／Li（摩尔比）为6,进料时间为60min时,产物光学性能最佳,雾度可降低至6％。     

2-氨基-6-硝基苯并噻唑的合成研究

研究了以对硝基苯胺为原料，在催化剂的作用下，合成2－氨基－6－硝基苯并噻唑。其适宜的工艺条件为：n（对硝基苯胺）：n（硫氰酸胺）：n(苯）＝1：1．15：6．5，反应温度为80－85℃，反应时间为10h；n(对硝基苯基硫脲）：n(催化剂）＝1：0．093，室温反应，反应时间为2h。产品收率为64．5％，纯度≥99％。     

苯乙酮酸的制备

苯乙烯在碱性水溶液中由高锰酸钾氧化制取苯乙酮酸，其中n(苯乙烯）：n（高锰酸钾）＝1：2．74，n（氢氧化钠）：n（高锰酸钾）＝1：2．5，反应温度为67－70℃时，产率为71．8％。     

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。