有机硅改性丙烯酸阳极电泳漆的合成

以乙醇为溶剂,将正硅酸乙酯(TEOS)与乙烯基三乙氧基硅烷(VTEOS)经酸催化合成了一种表面带有乙烯基的活性二氧化硅粒子,然后将其与丙烯酸树脂聚合得到透明的有机硅改性阳极电泳漆。研究了有机硅的添加方式对反应过程,有机硅含量对改性丙烯酸树脂的玻璃化转变温度、黏度以及电泳漆性能的影响,采用傅里叶变换红外光谱、差示扫描量热和热重分析等对改性丙烯酸树脂进行了表征。结果表明,有机硅的最佳添加方式是与部分单体预混后逐滴滴加。随着有机硅含量的增大,改性丙烯酸树脂的黏度、玻璃化转变温度和耐热性提高。当有机硅添加量为0.8%~1.2%时,电泳漆膜的综合性能较好。     

环氧-丙烯酸电泳漆的合成与应用

将改性环氧树脂和改性丙烯酸树脂混合乳化,合成了环氧–丙烯酸电泳漆。与原环氧型电泳漆相比,新合成的电泳漆的机械性能和耐盐雾性能均达到企业标准,人工加速老化试验400h后,漆膜完好,色差ΔE=0.24。按同样的原理,往原环氧电泳漆中加入丙烯酸树脂,使其转变成环氧–丙烯酸电泳漆。车架涂装生产证明,该电泳漆膜克服了原来涂层耐老化性差的问题。采用混合而非整槽更换的方式,既节约了成本,又利于环保。     

聚甲基苯基硅氧烷改性环氧树脂的合成与应用

聚甲基苯基硅氧烷(PMPS)接枝改性E-20环氧树脂.通过对环氧值、红外光谱(IR)和差热分析(DSC)分析表明有机硅成功接枝了环氧树脂且环氧基保持不变.探讨了有机硅含量对改性树脂固化体系玻璃化转变温度(Tg)、耐热性能的影响.结果表明:当m(E-20):m(DC-3074)=7:3时,化学改性树脂固化体系的耐热性能明显提高,同时作为耐高温防腐蚀涂料,此改性树脂固化物具有良好的涂膜性能.     

海洋操作平台钢结构用防护涂料的制备与性能

以聚己内酯、新戊二醇与顺丁烯二酸酐合成了聚酯树脂,然后与六亚甲基二异氰酸酯(HDI)反应以提高支化度,引入有机硅后再同丙烯酸单体反应制得丙烯酸改性聚酯树脂。以此丙烯酸改性聚酯树脂和适量的颜填料为甲组分、拜耳3390固化剂为乙组分,开发了适用于海洋气候的钢结构表面防护涂层。研究了顺丁烯二酸酐含量、丙烯酸改性聚酯树脂羟基含量、n(─NCO)∶n(─OH)值和聚合条件对面漆性能的影响。当顺丁烯二酸酐的用量为聚酯树脂的5%,自制的丙烯酸改性聚酯树脂羟基含量为4.5%±0.3%,n(─NCO)∶n(─OH)=1.1~1.4时,所制备的丙烯酸改性聚酯树脂面漆配以环氧富锌底漆及环氧云母氧化铁中涂漆得到的涂层体系能够满足海上平台钢结构的防护要求。     

紫外光固化丙烯酸酯改性有机硅的研究进展

综述了紫外光固化丙烯酸改性有机硅材料的研究进展,介绍了含丙烯酰氧基有机硅、含丙烯酸基有机硅、含丙烯酸和环氧基有机硅、聚氨酯改性丙烯酸类有机硅的合成、性能及应用,并展望了其发展趋势。     

紫外光固化有机硅改性环氧丙烯酸酯树脂的制备及性能

通过双酚F环氧树脂(EP)和丙烯酸的开环反应合成双酚F环氧丙烯酸酯树脂(BPFEA),然后以苯基三乙氧基硅烷(PTES)为改性剂接枝改性双酚F环氧丙烯酸酯树脂,系统研究不同改性比例下有机硅改性环氧丙烯酸酯树脂(PTES-BPFEA)的力学强度、柔韧性、耐热性等性能的影响。在10%的改性比例下有机硅改性树脂的综合性能最好,树脂的断裂伸长率达到17. 2%、柔韧性为1mm、铅笔硬度为6H,且树脂的吸水率较低,树脂的耐热性和耐碱性都得到增强。     

环氧化硅油改性邻甲酚醛环氧树脂的研究

采用侧基环氧化硅油(ES)及其改性物(PSA)改性邻甲酚醛环氧树脂(ECN),制备出一系列可用于电子封装等具有高韧性高耐热性的环氧基料。通过对固化物的冲击强度、拉伸强度、断裂伸长率和玻璃化转变温度(Tg)以及断裂面形态的测定,探讨了改性方法、有机硅组成与含量等对改性材料性能的影响。结果表明,用有机硅改性ECN后,其韧性和耐热性均有不同程度的提高,且环氧值高的ES和PSA的改性效果较好。其中环氧树脂经10份(质量份数,下同)ES-16或10份PSA-16改性后,韧性和耐热性均提高,符合电子封装等材料的改性要求,后者的耐热效果更为显著,Tg达183.46℃,比未改性环氧树脂提高了近20℃。     

有机硅改性环氧树脂的合成与性能

热熔法制备了系列聚甲基苯基硅氧烷(PMPS)改性环氧树脂,通过环氧值、红外光谱(IR)和凝胶色谱(GPC)分析表明,有机硅接枝到了环氧树脂上,且环氧基保持不变。探讨了改性方法、有机硅含量对改性树脂固化体系的微观形态、韧性及耐热性的影响。实验表明,当m(E-20)∶m(DC-3074)=7∶3时,化学改性树脂固化体系的韧性和耐热性能明显提高,玻璃化转变温度(Tg)为88.33℃,质量损失50%时的热分解温度(Td)为487.80℃,分别比物理改性环氧树脂提高了52.63℃和36.75℃,同时此改性树脂固化物还具有优良的涂膜性能。     

环氧酯改性苯丙树脂防锈乳液的合成研究

首先由亚麻油酸(FA)和E44按物质的量比n(FA)∶n(E44)=1∶1合成环氧酯;再以苯乙烯、甲基丙烯酸甲酯、丙烯酸丁酯为主要单体,丙烯酰胺、丙烯酸和乙烯基三(异丙氧基)硅氧烷为交联单体,环氧酯为改性单体,采用半连续种子聚合方法合成环氧酯改性有机硅苯丙乳液。研究了乳化剂的种类、用量及配比、交联单体及改性单体用量对乳液及涂膜性能的影响。确定复合乳化剂(SR-10/RP90)的最佳用量为2.5%,最佳配比为m(SR-10)∶m(RP90)=1∶1。实验发现:当丙烯酸用量为2%,丙烯酰胺用量为1.5%,乙烯基三(异丙氧基)硅氧烷用量为6%,环氧酯用量为10%,可以合成出性能优异的环氧酯改性有机硅苯丙乳液。由其制备的水性防锈涂料,具有良好的防锈性能。     

有机硅低表面能/自抛光海洋防污涂料的制备

采用接枝共聚的方法,即环氧和丙烯酸反应,环氧开环的同时生成带有羟基的丙烯酸单体,加入引发剂结合另外2种丙烯酸单体,在催化剂的作用下接入有机硅,制得有机硅环氧丙烯酸树脂。讨论了环氧树脂的用量对涂膜性能的影响、涂料的水解特性,并进行了实海挂板实验。结果表明:当环氧的用量为10%时,制备的防污涂料与水的接触角达到133°,附着力1级;有机硅/环氧改性丙烯酸树脂制得的防污涂料在海水中能够稳定地水解,兼具低表面能和自抛光的特性,实海挂板实验结果表明,涂料具有良好的防污性能。     

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。