有机耐高温涂层的制备及影响因素

以黏度为2400、3900和5300的树脂和改性环氧有机硅树脂为基料,添加钛白粉、氢氧化铝等不同的无机填料和其他添加剂,制备耐高温涂料。测试其性能,考察不同种类填料和助剂的添加量对耐高温涂料性能的影响。结果表明,改性环氧有机硅树脂+8%的氢氧化铝+10%钛白粉配方,涂层具有更好的耐冲击性、表面硬度、附着力及耐热性能。     

环氧改性有机硅耐热涂料的配方研究

以HG-43环氧改性有机硅树脂为基料,配以金属氧化物和硅酸盐类填料,制备了环氧改性有机硅耐热涂料。讨论了树脂含量以及空心玻璃微珠和阻燃剂的用量对涂料性能的影响,采用热失重分析、隔热性能和氧–乙炔烧蚀试验等方法对涂料的耐热性能进行了表征。结果表明,当HG-43环氧改性有机硅树脂用量为30%、空心玻璃微珠的用量为18%、复合阻燃剂用量为9%时,所制备的环氧改性有机硅耐热涂料的附着力2级,硬度4H,氧–乙炔线烧蚀率为0.278 mm/s,质量烧蚀率为0.075 8 g/s,具有良好的隔热性能。     

颜填料对环氧改性有机硅耐高温涂料综合性能的影响

以刚玉粉和钛白粉为颜填料,以环氧改性有机硅树脂为基料,制备了环氧改性有机硅耐高温涂料。研究了不同颜基比和不同颜填料配比对环氧改性有机硅树脂耐高温涂料综合性能的影响。     

含羟基柔性链段纳米二氧化硅的制备及其对高速列车涂层性能的影响研究

采用两步法对纳米二氧化硅进行有机无机杂化改性,首先通过异氰酸酯的桥接作用,在纳米二氧化硅的表面引入环氧树脂分子,再利用环氧基团的碱式开环反应,形成可参与交联固化的羟基,制备了表面接枝含羟基柔性链段的纳米填料,研究了纳米二氧化硅不同用量对涂层材料力学性能与耐磨性能的影响。结果表明,有机无机杂化改性后的纳米二氧化硅能与有机树脂发生化学反应,改善了无机纳米二氧化硅在涂层中的分散性,提高了有机/无机的界面相容性,从而提高了涂层的韧性和致密性。当改性纳米二氧化硅的添加量为6%时,与添加未改性纳米填料的涂层相比,其耐磨性提高了24%,拉伸强度提高了25%,断裂伸长率提高了50%,涂层的饱和吸水率降低了40%。     

含羟基柔性链段纳米二氧化硅的制备及其对高速列车涂层性能的影响研究

采用两步法对纳米二氧化硅进行有机无机杂化改性,首先通过异氰酸酯的桥接作用,在纳米二氧化硅的表面引入环氧树脂分子,再利用环氧基团的碱式开环反应,形成可参与交联固化的羟基,制备了表面接枝含羟基柔性链段的纳米填料,研究了纳米二氧化硅不同用量对涂层材料力学性能与耐磨性能的影响。结果表明,有机无机杂化改性后的纳米二氧化硅能与有机树脂发生化学反应,改善了无机纳米二氧化硅在涂层中的分散性,提高了有机/无机的界面相容性,从而提高了涂层的韧性和致密性。当改性纳米二氧化硅的添加量为6%时,与添加未改性纳米填料的涂层相比,其耐磨性提高了24%,拉伸强度提高了25%,断裂伸长率提高了50%,涂层的饱和吸水率降低了40%。     

环氧有机硅类烧蚀涂料研究进展

从烧蚀机理、基体树脂、功能填料、工艺制备等方面论述了环氧有机硅烧蚀涂料的研究现状。介绍了环氧改性有机硅树脂的制备方法,以性能分类详细汇总了各类功能填料的作用机理,并对该研究领域的发展前景进行了展望。     

低压高效石墨烯复合涂料的电热性能研究

分别在环氧、环氧改性有机硅、乙烯基树脂3种体系中,以石墨烯为导电填料,研究不同含量的石墨烯对涂料电热性能的影响。结果表明:石墨烯填充在乙烯基树脂中时,发热效率最高,石墨烯复合环氧树脂的涂层附着力最好;石墨烯与环氧改性有机硅复合综合性能最佳。当温度为25℃时,石墨烯含量为3%的环氧改性有机硅涂层在20 V低电压下通电2 min,涂层维持温度为61℃,涂层功率为12.5 W/dm~2,而且涂层物理性能最佳。石墨烯复合环氧改性有机硅树脂的电热涂料能满足安全、便捷、高效的要求。     

环氧改性有机硅防热涂料研究进展

介绍了环氧改性有机硅涂料的防热机制,阐述了以环氧树脂物理改性和化学改性有机硅涂料的研究进展,讨论了功能填料对涂层防热、耐候、机械强度等性能的积极影响,并对该研究领域的发展前景进行了展望。     

聚酰胺改性对介孔SiO_2填料/环氧涂层性能的影响

通过红外、拉伸试验、电化学阻抗谱(EIS)研究了聚酰胺(PA)改性的介孔SiO_2(MCM-41)填料对环氧复合材料的力学性能和耐腐蚀性能的影响。实验结果表明:相对于添加未PA改性的SiO_2填料/环氧涂层,添加了PA改性的介孔SiO_2填料/环氧涂层柔韧性和耐蚀性提高。     

常温固化环氧有机硅共缩聚树脂耐高温涂料的研究

采用一种国产有机硅树脂和环氧树脂,在160～240℃共缩聚合。以低分子量聚酰胺为固化剂,钛白粉、铝粉为耐温填料,制备一种有广泛用途的、常温固化的环氧有机硅耐高温涂料。采用正交实验法研究了共缩聚合温度、原料配比等因素对涂层耐高温性能的影响。     

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。