十二烷基磺酸柱撑稀土类水滑石对PVC热稳定作用

采用共沉淀法制备了十二烷基磺酸柱撑镁铝镧类水滑石,采用X射线粉末衍射(XRD)、红外光谱(FT-IR)进行表征。将其应用于聚氯乙烯(PVC)中,利用刚果红试纸法、转矩流变仪等探讨了其对PVC热稳定性的影响,并通过紫外光谱分析了热稳定机理。结果表明:十二烷基磺酸柱撑镁铝镧类水滑石(简称产品)对PVC长期热稳定性较好。紫外光谱(UV)分析表明产品在加热初期可抑制PVC降解中短链共轭多烯的增长。产品与硬脂酸锌、季戊四醇复合使用时能产生良好的协同效应,可有效提高PVC热稳定性。     

PVC用月桂酸柱撑锌铝铈类水滑石热稳定剂的制备与性能

采用共沉淀法制备了一种新型的PVC热稳定剂——月桂酸柱撑锌铝铈三元类水滑石,采用X射线粉末衍射(XRD)、傅立叶变换红外光谱(FTIR)对其结构进行了表征。利用刚果红法、转矩流变仪等考察其对PVC性能的影响,并研究了与常见热稳定(助)剂的协同效应。结果表明,月桂酸柱撑锌铝铈类水滑石的长期热稳定性较好。当月桂酸柱撑锌铝铈类水滑石与季戊四醇、硬脂酸锌的质量比为1.5∶1∶1时协同效果较好,当3份该复合热稳定剂加入到100份PVC时,可使PVC静态及动态热稳定时间分别达到118min和47min,扭矩适中,拉伸强度为49.1MPa,断裂伸长率为51.8%,冲击强度为5.8kJ/m2,能够提高PVC的热稳定性能和力学性能。     

硬脂酸柱撑类水滑石的制备及应用

采用离子交换法制备了硬脂酸柱撑类水滑石,并用红外光谱分析对其进行了表征.通过HAAKE流变仪、颜色测定仪研究了硬脂酸柱撑类水滑石与钙锌热稳定剂并用时的热稳定性,重点考察了水滑石的结构对PVC稳定性能的影响.结果表明硬脂酸柱撑类水滑石与钙皂/锌皂复配显著改善了PVC热老化过程中的初期着色性.     

硬脂酸柱撑类水滑石的制备及应用

采用离子交换法制备了硬脂酸柱撑类水滑石,采用红外光谱分析对其结构进行了表征。通过HAAKE流变仪、颜色测定仪研究了硬脂酸柱撑类水滑石与钙锌热稳定剂并用时的热稳定性,重点考察了水滑石的结构对PVC稳定性能的影响。结果表明硬脂酸柱撑类水滑石与钙皂/锌皂复配显著改善了PVC热老化过程中的初期着色性。     

硬脂酸柱撑类水滑石的制备及应用

采用离子交换法制备了硬脂酸柱撑类水滑石，采用红外光谱分析对其进行了表征。通过HAAKE流变仪、颜色测定仪研究了硬脂酸柱撑类水滑石与钙锌热稳定剂并用时的热稳定性，重点考察了水滑石的结构对PVC稳定性能的影响。     

硬脂酸插层钙/锌稀土类水滑石对PVC的热稳定作用

采用共沉淀法分别合成了硬脂酸插层钙铝镧类水滑石和硬脂酸插层锌铝镧类水滑石,并通过X射线衍射和红外光谱进行结构表征。采用刚果红法、烘箱变色法、电导率法等考察钙/锌水滑石不同配比对聚氯乙烯(PVC)的热稳定作用,利用转矩流变仪和力学性能测试仪测定了最佳复配体系的流变性能和力学性能。结果表明,钙/锌水滑石复配后表现出良好的协同热稳定作用,能够有效地延长PVC的热稳定时间并抑制初期着色;其份数比为2.25/0.75时效果最佳,与添加相同量的硬脂酸钙/锌相比,表现出更优的热稳定性、流变性能和力学性能。     

镁铝型水滑石复合热稳定剂的研究

采用加热瞬间沉淀法制备镁铝水滑石,对所得产物进行FT-IR、XRD分析,用刚果红法测试镁铝水滑石单一作用以及和硬脂酸钙复合作用时对PVC热稳定性的影响.结果发现:水滑石单独作用时,占PVC 3％的水滑石效果最佳,PVC热稳定时间为37 min,热稳定温度为203℃.水滑石与硬脂酸钙复合作用时,水滑石占复合热稳定剂总量的80％时效果最佳,热稳定时间为51 min,热稳定温度为213℃,水滑石与硬脂酸钙有较好的协同作用.     

镧镁水滑石的制备及其对PVC热稳定性能的影响

采用共沉淀法,改变La~(3+)/Mg~(2+)投料摩尔比和陈化温度制备了一系列镧镁水滑石。采用镧镁水滑石作为PVC热稳定剂,通过刚果红实验和动态热稳定性实验,探讨了不同制备条件下镧镁水滑石对PVC静态、动态热稳定性能的影响。结果表明,La~(3+)/Mg~(2+)投料摩尔比和陈化温度是影响镧镁水滑石中镧含量的主要因素。镧镁水滑石可以显著提高PVC的静态、动态热稳定性能。镧镁水滑石制备过程中,陈化温度是影响PVC/镧镁水滑石热稳定性和加工性能的关键因素。当陈化温度分别为90、100和110℃时,PVC/镧镁水滑石静态、动态热稳定性能明显高于陈化温度为70℃时的性能;当陈化温度为100℃时,镧镁水滑石对PVC的静态、动态热稳定性的影响较优,同时,PVC/镧镁水滑石的塑化扭矩较低,相应的加工能耗较低。     

镁铝水滑石的制备与性能研究

采用盐碱共沉淀法制备镁铝水滑石,采用XRD、FT-IR和粒度分析等手段对合成样品进行分析和表征,利用静态热老化法和静态热稳定性实验研究了镁铝水滑石稳定剂在聚氯乙烯（PVC）中的热老化性能和热稳定性 能。实验结果表明：镁铝水滑石是良好的PVC热稳定剂和热老化剂,热稳定剂实验的最佳配方比为m（PVC）∶m（硬脂酸）∶m（镁铝水滑石）= 100∶2∶1.2;热老化实验的最佳配方为m（PVC）∶m［邻苯二甲酸二辛酯（DOP）］∶m（硬脂酸）∶ m（镁铝水滑石）=100∶70∶2∶2。     

十二烷基苯磺酸柱撑类水滑石的热稳定性研究

采用焙烧复原法制备了一种新型PVC热稳定剂——十二烷基苯磺酸柱撑类水滑石，采用红外光谱分析、热重分析、X射线粉末衍射分析对其进行了表征，并测定了采用十二烷基苯磺酸柱撑类水滑石复配的复合热稳定剂RZL1的热稳定性能。结果表明：采用十二烷基苯磺酸柱撑类水滑石复配的RZL1初期热稳定性较好，与日本产的稀土复合稳定剂相当，长期热稳定性优于国产稀土复合稳定剂。     

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。