NDQ催化剂催化丙烯聚合

采用以二醇酯为内给电子体合成的NDQ催化剂,在5 L高压釜中催化丙烯本体聚合,评价了NDQ催化剂的聚合性能.结果表明:NDQ催化剂具有较高聚合活性、立构定向性;NDQ催化剂在低氢气浓度下氢调不敏感,适宜生产低熔体流动速率的树脂;得到的聚丙烯具有相对分子质量分布宽的特点.     

新型MgCl2/PET复合载体催化剂及丙烯聚合Ⅱ.丙烯聚合

用MgCl2和聚对苯二甲酸乙二酯（PET）制备了一种新型复合载体,负载钛后应用于丙烯催化聚合。考察了聚合温度、助催化剂用量、氢气加入量及外给电子体种类等对催化剂和产物性能的影响。聚合温度为70℃、n（Al）／n（Ti）为200、氢气加入量为1L,采用环己基甲基二甲氧基硅烷作为外给电子体时,催化剂具有较高的催化活性,同时聚丙烯具有较高的等规指数,相对分子质量分布宽。     

以9-烷氧甲基-芴甲酸酯作内给电子体的Ziegler-Natta催化剂

设计并合成了一系列9-烷氧甲基-芴甲酸酯类化合物,对其进行了核磁共振氢谱表征,并将其作内给电子体用于制备Ziegler-Natta催化剂,且对所制催化剂进行了丙烯聚合性能评价。结果表明:催化剂活性较高,用该催化剂制备的聚丙烯具有较高等规指数。此外,该催化剂在聚合过程中通过配合使用不同外给电子体能产生协同作用,在保证催化剂活性的同时提高聚丙烯等规指数。在同样的催化剂制备工艺和聚合条件下,与用邻苯二甲酸二正丁酯、9,9-双甲氧甲基芴和2,3-二异丙基琥珀酸乙酯作内给电子体的催化剂相比,该系列的部分催化剂具有相当或更优的活性和立体定向性。     

NDQ型催化剂在聚丙烯新产品开发中的应用

NDQ型催化剂以二醇酯为内给电子体,在5 L高压釜中进行了催化剂丙烯聚合性能评价。采用NDQ型催化剂,以环己基-甲基-二甲氧基硅烷为外给电子体,在单环管聚丙烯装置上开发了聚丙烯PPH-M12,PPT5015,PPB2025等产品。根据NDQ型催化剂的性能特点优化了聚合工艺参数(包括预聚合温度、聚合温度和聚合压力)。结果表明:用NDQ型催化剂制备的PP的相对分子质量分布较宽,分子链规整度较高,具有更好的加工性能和力学性能,并且不含邻苯二甲酸酯类塑化剂。     

钛基催化聚酯研究

对自制钛基聚酯催化剂在聚合工艺及合成产品性能方面进行了研究。结果表明,该钛催化剂用于聚酯生产时,可以生产出具有低二甘醇含量、较高的玻璃化转变温度和熔点的聚酯。     

中分子量聚乙烯齐格勒-纳塔催化剂的研究

合成了一种钛系齐格勒-纳塔烯烃聚合催化剂，该催化剂具有较高的乙烯聚合活性，其乙烯聚合动力学平稳，氢调敏感,所得到的乙烯聚合物具有中等分子量分布。     

中国专利

用于烯烃聚合的催化剂组分及其制备方法本发明提供了一种用于烯烃聚合的催化剂组分的制备方法及其获得的催化剂组分。该方法中采用以球形卤化镁加合物为载体,并采用以二醇酯类化合物与1,3-二醚类化合物复配作为内给电子体所制备的球形催化剂,通过控制内给电子体的反应温度及控制催化剂的洗涤程度使所得催化剂在用于烯烃聚合,尤其是丙烯聚合时,显示了超高的聚合活性和较高的立构定向性,并且即使在较低烷基铝浓度下仍保持了很高的活性,所得聚合物的相对分子质量分布较宽,灰分相对较低。     

一种Ziegler-Natta载体催化剂用于乙烯淤浆聚合的研究

对载体型催化剂进行乙烯淤浆聚合,研究了催化剂的乙烯聚合动力学,分析了聚合温度、压力,助催化剂及氢气加入量对聚合结果的影响.研究结果表明,最佳聚合条件为:聚合时间2 h,聚合温度80℃,聚合压力0.83MPa,Al/Ti比(物质的量比)115,H2/C2H4比(压力比)0.52.在此条件下,催化剂具有较高的催化效率,聚合物形态较好,表观密度较高,流动性很好.     

DQC-700型催化剂催化丙烯聚合

采用仪器分析和化学分析法表征了DQC-700型催化剂的组成、结构及其颗粒形态。以环己基甲基二甲氧基硅烷为外给电子体,用DQC-700型催化剂催化丙烯本体聚合,评价了预聚合温度对预聚合倍数、预聚物等规指数和预聚物粉料粒径分布的影响,研究了催化剂的聚合性能和聚丙烯粉料中的细粉含量。结果表明:DQC-700型催化剂具有较窄的粒径分布(粒径分布跨度1.0)、较大的比表面积(300 m2/g)、较高的聚合活性[45 kg/(g·h)]和立构定向性(聚丙烯等规指数98%)。     

Prec催化剂在工业本体装置上的应用

文章研究无须预聚直接聚合生产而不发生破碎的球形催化剂,使用该催化剂在工业本体上进行了丙烯聚合研究,研究了丙烯聚合过程中催化剂催化聚合产生热量和压力变化情况。结果表明：催化剂的初始聚合活性释放比较平稳。通过电子显微镜观测和粒度分析,表明催化剂具有良好的球形形貌,破碎少,粒径分布窄。DSC分析表明,催化剂具有较低熔点和较高熔融焓的特性。该催化剂不经过预聚依然能够在聚合过程中保持颗粒的完整性,得到形貌良好的聚丙烯颗粒,性能达到应用要求,可以进行大规模催化剂生产应用。     

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。