PU/PA纳米粒子改性酚醛树脂胶粘剂的研究

采用自乳化法制备PU/PA纳米粒子,并对酚醛树脂进行增韧改性.考查了丙烯酸酯单体种类、用量以及环氧树脂用量对改性酚醛树脂粘接性能的影响.借助TG、DSC、SEM和TEM对改性酚醛树脂体系的耐热性能、固化反应和微观形态进行了表征.结果表明,PU/PA纳米粒子的加入使酚醛树脂的常温和高温粘接强度显著增加,提高了酚醛树脂的固...     

保温高分子材料的研究进展

综述了硬质聚氨酯泡沫塑料与聚苯乙烯保温材料的阻燃改性、酚醛树脂的增强增韧改性、相变材料保温性能的研究进展,以及这些材料在建筑工程领域的应用。硬质聚氨酯泡沫塑料和聚苯乙烯保温材料的阻燃改性主要是通过在基体中添加无机或有机阻燃剂来实现,酚醛树脂的增强增韧主要是通过添加高分子纤维、无机纤维或纳米粒子等实现,相变材料通过相转变过程中的吸热和放热来达到保温效果,通常与其他保温材料共同使用。     

微-纳米无机粒子改性聚丙烯材料的最新进展

综述了近年来微-纳米无机刚性粒子填充改性聚丙烯(PP)材料的最新进展,介绍了微米级、纳米级和微-纳米组合无机刚性粒子的添加对PP复合材料性能的影响。无机刚性粒子越细,越有利于PP材料的增强增韧;无机刚性粒子的表面改性处理对复合材料的微观结构和性能有重要影响。微米无机刚性粒子可提高PP材料的抗冲击强度与刚性,但强度会有所降低;均匀分散的无机纳米粒子同时起到增强增韧的双重作用;具有粒径级的组合粒子的填充改性优于单一无机粒子。     

纳米粒子增韧聚氯乙烯的研究

综述了纳米粒子在聚氯乙烯(PVC)增韧改性中的研究现状及作用机理,分别介绍了纳米CaCO3、纳米SiO2、纳米黏土及“核壳”纳米粒子等在PVC增韧改性中的研究与应用,得出了纳米复合技术在PVC增韧改性中均能提高材料韧性和强度的特点。最后,对发展价格低廉的新型纳米增韧增强粒子进行了展望。     

SiO2纳米粒子改性填充PC的力学与流变性能

采用SiO2纳米粒子填充改性聚碳酸酯(PC),为使无机纳米粒子在基体PC中分散均匀,经硅烷偶联剂KH-550对SiO2纳米粒子进行表面处理,分析了改性SiO2纳米粒子对复合材料机械与加工性能的影响,并对复合材料进行了分析表征,探讨了无机刚性纳米粒子填充改性典型工程塑料PC的特点并探索其增强增韧的机理,研究了复合物的粘流变性能. 结果表明,改性SiO2纳米粒为球形,在PC基体中分散均匀,湿法改性制备的PC/SiO2纳米粒子复合材料的力学拉伸性能和流变性能最好.     

纳米无机粒子改性聚丙烯研究进展

综述纳米CaCO3、纳米TiO2、纳米SiO2对聚丙烯(PP)的改性研究进展。重点讨论了纳米无机粒子对PP改性的机理和影响因素。结果表明,纳米粒子可改善PP的力学性能(增强、增韧)、抗老化性能及抗菌性能等。     

纳米SiO_2在塑料中的应用

本文论述了纳米SiO2粒子增强增韧塑料的机理,纳米SiO2粒子改性聚合物的方法,复合材料的制备技术及其性能。并讨论了近年来纳米SiO2改性塑料的发展状况。     

纳米SiO2在塑料中的应用

本文论述了纳米SiO2粒子增强增韧塑料的机理,纳米SiO2粒子改性聚合物的方法,复合材料的制备技术及其性能.并讨论了近年来纳米SiO2改性塑料的发展状况.     

纳米无机刚性粒子改性聚丙烯研究进展

综述了纳米CaCO3、纳米TiO2、纳米SiO2对聚丙烯（PP）的改性研究进展。重点讨论了纳米无机粒子对PP改性的机理和影响因素。结果表明，纳米粒子可改善PP的力学性能（增强、增韧）、抗老化性能及抗菌性能等。     

纳米SiO2在塑料中的应用

本文论述了纳米SiO2粒子增强增韧塑料的机理,纳米SiO2粒子改性聚合物的方法,复合材料的制备技术及其性能.并讨论了近年来纳米SiO2改性塑料的发展状况.     

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.     

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。     

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.