水性环氧树脂/双氰胺体系的研究

多官能团酚醛环氧树脂F-51与适量二乙醇胺反应,制得一种分子中含环氧基和亲水基团的改性F-51环氧树脂,该树脂成盐后具有良好亲水性。以双氰胺为固化剂,对体系的反应性及固化物主要性能进行研究,结果表明固化反应起始温度显著降低,固化膜的硬度达6H,并具有很强的附着力。     

二乙醇胺改性水性环氧树脂的制备研究

采用二乙醇胺对双酚A型环氧树脂(E-44)进行化学改性引入亲水性基团,制备出了稳定性良好的水性环氧树脂。通过研究二乙醇胺用量、反应温度对水性环氧树脂体系稳定性的影响,确定了最佳的原料配比;研究了水性环氧树脂的粒径分布。研究表明:随着二乙醇胺用量的增加,环氧树脂的亲水性增强。随着二乙醇胺与环氧基物质的量比的增大,水性环氧树脂的粒径变小,当二乙醇胺与环氧基的物质的量比为0.5∶1时,能够制备出性能稳定的环氧树脂水溶液。     

二乙醇胺改性水性环氧树脂乳液的制备及其性能研究

以二乙醇胺(DEOA)、环氧树脂E-51为主要原料,合成了DEOA化学改性的自乳化水性环氧树脂乳液,并与水性环氧树脂固化剂按一定比例配制成涂膜。采用红外光谱对改性环氧树脂结构进行表征,通过纳米粒度分析仪和透射电镜(TEM)研究了环氧树脂乳液的粒径和形貌,同时研究了反应温度对环氧基转化率的影响,DEOA加入量对乳液稳定性、粒径的影响。结果表明,随着DEOA用量的增加,环氧树脂乳液的稳定性提高,粒径减小且分布变窄。当n(DEOA):n(环氧基)=0.35:1时,乳液粒径约30~60 nm,制备的涂膜铅笔硬度为3H,柔韧性为1 mm,附着力为1级,耐冲击性为50 kg/cm。     

水性环氧固化剂的制备及其涂膜性能研究

采用丙烯酸丁酯改性三乙烯四胺(TETA),以环氧树脂E-51为封端剂,制备水性环氧固化剂。研究表明:在反应温度为70℃、反应时间为3 h、n(三乙烯四胺加成物)∶n(环氧树脂)为2∶1时,制备的水性环氧固化剂性能优良,与环氧乳液配制的涂料的涂膜具有硬度高,附着力好、流平性好、光泽高等优点。     

水溶性甲基丙烯酸改性光敏酚醛环氧树脂的制备及性能

以含环氧基的光敏性甲基丙烯酸酚醛环氧树脂为原料合成了一种可以在质量分数为1%的碳酸钠溶液中溶解的含环氧基的光敏性甲基丙烯酸酚醛环氧树脂(AMAFEE),研究了该树脂的合成条件及工艺.发现当反应温度为95℃、选用溴化季铵盐作为反应的催化剂、反应时间为3 h可获得在低浓度碱溶液中溶解的涂料用树脂AMAFEE.当树脂中投料比n(环氧基)∶n(羟基)∶n(琥珀酸酐)=5∶5∶5时,以此树脂制备的涂料具有优良的力学性能.光敏实验证明,AMAFEE树脂中的碳碳双键具有较高的光学反应活性,光照15 s后转化率可达60%以上.     

二乙醇胺对环氧阴极电泳涂料固化温度的影响

在环氧阴极电泳涂料的生产过程中,采用胺对环氧基团开环是重要的一步反应。由开环反应得到的羟基,在一定温度下与封闭异氰酸酯发生交联反应,得到坚韧耐用、满足各项需求的电泳漆漆膜。本研究针对二乙醇胺用量对环氧阴极电泳涂料固化温度的影响进行研究,发现在其他条件完全相同的情况下,随着二乙醇胺用量的增加,漆膜的固化温度会逐渐降低。当环氧基:二乙醇胺=2∶1(物质的量的比)时,固化温度为145℃;当环氧基:二乙醇胺=1.8∶1时,固化温度140℃;环氧基:二乙醇胺=1.5∶1时,固化温度可低至130℃。进一步提高二乙醇胺用量,则会影响最终的乳化效果,对乳液稳定性产生负面影响。     

涂料用水溶性光敏树脂的制备及性能

以含环氧基的光敏性丙烯酸酚醛环氧树脂为原料合成了一种可以在 1 %的碳酸钠溶液中溶解的光敏性酚醛环氧树脂 (AAFEE) ,研究了该树脂的合成条件及工艺。发现当反应温度为 95°C、选用溴化季铵盐作为反应的催化剂、反应时间为 3h可获得在低浓度碱溶液中溶解的涂料用树脂(AAFEE)。当树脂中 n(环氧基 )∶n(羟基 )∶n(琥珀酸酐 ) =3∶ 7∶ 6、3∶ 7∶ 5时 ,以此树脂制备的涂料具有优良的力学性能。光敏实验证明 ,AAFEE树脂中的碳碳双键具有较高的光学反应活性 ,光照 1 5s后转化率可达 60 %以上。     

非离子型水性环氧树脂固化剂的合成与性能研究

采用低相对分子质量的环氧树脂E-51与聚醚-4000反应制备环氧改性聚醚加成物,再与多乙烯多胺进行反应制备胺封端的聚醚-环氧-胺加成物,最后采用单环氧化合物进行封端,合成非离子型水性环氧固化剂,实验表明工艺可行。对环氧E-51改性聚醚-4000合成过程中的各影响因素进行了研究,并对非离子型水性环氧固化剂的固化性能进行了评价。最佳配方与工艺为:n(环氧树脂E-51)∶n(聚醚-4000)2∶1,催化剂选用含三氟化硼(BF3)质量分数2%的乙醚溶液(60℃时加入,加入量为2%)。与现有的市售水性环氧固化剂固化性能相比,非离子型水性环氧固化剂固化的环氧体系的柔韧性和耐冲击性有大幅提高。     

低黏度季戊四醇改性环氧丙烯酸酯的研究

以季戊四醇为核分子,按一定物质的量比与环氧树脂进行酯化反应合成一种球状季戊四醇环氧酯,再用丙烯酸与季戊四醇环氧酯上的端环氧基进行酯化开环反应,合成了适用于电子束(EB)固化的低黏度季戊四醇环氧丙烯酸酯,并采用红外光谱对产物进行表征和分析。结果表明:1)季戊四醇与环氧树脂生成季戊四醇环氧酯的最佳反应条件为n季戊四醇∶n环氧树脂=0.15∶1.00、催化剂用量为0.5%、反应温度为95℃、反应时间2.5 h;2)季戊四醇环氧酯与丙烯酸反应的催化剂四丁基溴化铵用量为0.5%、阻聚剂对羟基苯甲醚用量为0.5%、反应温度为85℃、反应时间6 h,制得黏度为2.41 Pa.s的季戊四醇环氧丙烯酸酯。     

聚氨酯改性环氧树脂阴极电泳涂料的制备与性能研究

利用聚醚二元醇、二环己基甲烷 -4,4'-二异氰酸酯（ HMDI）合成— NCO封端的聚氨酯预聚体,再与环氧树脂（E-44）反应生成聚氨酯改性环氧树脂,聚醚二元醇、 HMDI与环氧树脂 E-44的物质的量比为 1∶2∶2。以聚氨酯改性环氧树脂为主体,用一乙醇胺（ MEA）和二乙醇胺（ DEA）对树脂进行环氧开环,封闭型异氰酸酯为固化剂,用乳酸进行酸化中和,加入去离子水乳化得到阴极电泳涂料。结果表明： n（MEA）∶n（DEA）∶n（聚氨酯改性环氧树脂） =4∶4∶3,固化剂用量为 21%,中和度 65%,并加入去离子水可调节成固体分为 12%的稳定阴极电泳涂料,涂料乳白并伴有蓝相。最后在工件上进行电泳涂装,得到表面光滑平整、硬度 3H、耐冲击性 50 cm、耐盐雾 500 h、柔韧性 1 mm、附着力 1级 的阴极电泳漆膜。     

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。