毒死蜱微胶囊悬浮种衣剂的制备研究

采用原位聚合法制备20%毒死蜱微胶囊悬浮种衣剂。以粒径和包封率为指标对乳化剂种类、囊芯比、调酸时间、固化时间和固化温度等条件进行单因素和正交优化设计。优化后的最佳反应条件为:农用乳化剂SP-EW3336用量3.5%,囊芯比1.0,调酸时间60 min,固化温度50℃,固化时间60 min,制得的微胶囊粒径为1.60±0.06μm,包封率可达77%。     

毒死蜱农药微胶囊剂制备工艺研究

为探讨溶剂挥发法制备毒死蜱微胶囊剂的工艺条件,本研究以聚甲基丙烯酸甲酯为囊壁材料,二氯甲烷为溶剂,水为连续相讨论芯材与壁材比、有机相与水相体积比,乳化剂浓度以及剪切乳化速度对毒死蜱微胶囊剂成囊的影响。研究结果证明成囊的最佳工艺条件:在室温条件下,以二氯甲烷溶解毒死蜱,芯材与壁材的比(w/w)为1∶2,有机相与水相的比(v/v)为15∶105~20∶100,以1.5%羟乙基纤维素(MW:20000)为乳化剂,有机相和水相混合后在15000 r/min下高速剪切乳化分散6 min,在室温下搅拌直至二氯甲烷完全挥发。在此条件下所得毒死蜱微胶囊剂呈球形,平均粒径约为8.5~8.8μm,包覆率在94.52%以上。     

响应面法优化三唑酮微胶囊的制备工艺

[目的]为三唑酮微胶囊的制备及三唑酮控制释放剂型的开发提供理论依据。[方法]以密胺树脂为壁材,采用原位聚合法制备三唑酮微胶囊,以包封率为评价指标,通过单因素法和响应面法优化试验,并研究了三唑酮微胶囊的物化性质。[结果]三唑酮微胶囊的最佳制备工艺为:以苯乙烯马来酸酐和十二烷基苯磺酸钠复配作为乳化剂,用量为0.82 g、壁材用量为14.43 g、反应初始温度20℃、转速800 r/min、反应的终点pH值为5、固化温度68℃、固化时间120 min,三唑酮微胶囊的包封率平均值可达85.31%,和预测模型值86.76%相比,相对误差仅为1.67%。[结论]响应面法能够有效的优化三唑酮微胶囊的制备工艺。     

聚苯乙烯包覆环氧树脂微胶囊的研制

以环氧树脂和稀释剂环氧丙烷丁基醚为囊芯,苯乙烯-二乙烯基苯为高分子囊壁材料,采用原位聚合法合成了一种全新的自修复微胶囊-聚苯乙烯包覆环氧树脂微胶囊。考察了不同种类与不同用量的乳化剂对囊芯与壁材溶液进行乳化以及反应温度、反应时间、引发剂添加方式等对聚苯乙烯包覆环氧树脂与活性稀释剂微胶囊合成工艺的影响。结果表明：实验成功合成了聚苯乙烯包覆环氧树脂微胶囊,最佳工艺条件为采用1％阿拉伯树胶作为乳化剂,先加入BPO引发反应5h后再加入过硫酸钾,反应温度在70～80℃,反应时间8h。     

界面聚合法制备聚脲蜂蜡相变微胶囊

以蜂蜡为微胶囊芯材,以甲苯-2,4-二异氰酸酯(TDI)和乙二胺(EDA)为单体,以辛基酚聚氧乙烯醚(OP-10)为乳化剂,采用界面聚合法制备聚脲蜂蜡相变微胶囊。探讨乳化剂用量、单体摩尔比和反应温度等因素对聚脲蜂蜡相变微胶囊的影响,并表征其包覆效果。结果表明,在乳化剂质量分数为2.40%,n(TDI)∶n(EDA)=1.2∶1.0,反应温度为70℃的条件下制备的聚脲蜂蜡相变微胶囊的平均粒径为70.3μm,耐热温度为210℃,相变温度为41℃,相变潜热为59.55 J/g。     

路面材料自修复微胶囊制备工艺研究

以环氧树脂为囊芯,明胶和阿拉伯胶为囊壁,十二烷基硫酸钠(SDS)为乳化剂合成自修复微胶囊。考察了囊材和芯材的比例、反应时间、体系的pH、乳化剂的用量等因素对自修复微胶囊包覆率影响。确定了制备自修复微胶囊的最佳工艺:即囊材和芯材的质量比为10∶9,加入15 mL质量分数为4%的SDS为乳化剂,在pH低于4.0时持续反应3 h合成包覆率为69.9%的自修复微胶囊。     

壳聚糖-阿拉伯胶/雷公藤微胶囊的制备

以壳聚糖、阿拉伯胶为壁材,雷公藤提取物为芯材,采用复凝聚法制备壳聚糖-阿拉伯胶/雷公藤微胶囊。以雷公藤提取物含量、芯材比、反应温度、搅拌转速为考察因素,以载药量、包封率为评价指标,通过正交实验对制备工艺进行优化,并测定了微胶囊的药物释放性能。结果表明,微胶囊的最佳制备工艺为:雷公藤提取物含量15%、芯材比1∶1(g∶g)、反应温度45℃、搅拌转速500r·min~(-1),在此条件下,载药量与包封率分别达到86.22%和54.75%,所得微胶囊呈球形,未发生粘连现象,其在人工肠液中的药物释放性能稳定性高,50min左右即可释放出雷公藤有效成分。     

农药2,4-D微胶囊悬浮剂的研制

以脲醛树脂为壁材,采用原位聚合法制备2,4-D微胶囊悬浮剂。在固定合成脲醛树脂反应条件的基础上,通过改变成囊过程中囊心与囊壁比、固化剂种类及用量、搅拌速度、固化时间、固化温度、加酸时间、终点pH等的不同,进一步研究上述不同条件对微胶囊粒径大小、粒径分布范围、微胶囊包囊率的影响,从而筛选最优的成囊反应条件。实验结果显示该微胶囊能够满足实际需要。     

用于自内冷溶液除湿的复配石蜡微胶囊的特性

以三聚氰胺?甲醛树脂为胶囊壁材、固液复配石蜡为胶囊芯材,采用原位聚合法制备了用于自内冷溶液除湿的相变材料微胶囊,研究了单一或不同类型乳化剂复配、乳化剂用量对相变材料微胶囊粒径、微观形貌及热性能的影响. 结果表明,非离子乳化剂NP-10与阴离子乳化剂SDBS复配所制微胶囊相变潜热较低,非离子乳化剂Span80和Tween80按质量比1:1复配、乳化剂占芯材质量的60%、乳化转速为1000 r/min时,所制微胶囊综合性能最佳,表面光滑致密,分散性良好,粒径均一,平均粒径为0.45 ?m,相变潜热为52.48 J/g,囊芯含量为58.44%,相变温度适用于以LiCl溶液为除湿剂的自内冷溶液除湿系统.     

高强度明胶-阿拉伯胶电泳显示微胶囊的制备

以球磨法制备的炭黑、TiO2的四氯乙烯电泳分散体系为囊芯,以明胶、阿拉伯胶为壁材,采用复凝聚法制备了电泳微胶囊.详细研究了壁材比,反应温度、表面活性剂浓度、pH的控制、固化条件等因素对微胶囊性能的影响,并采用落球冲击实验对微胶囊强度进行了表征.结果表明,微胶囊制备的优化条件为明胶与阿拉伯胶用量比为1∶1(W∶w),反应温度50℃,十二烷基硫酸钠(SDS)浓度0.001g·mL-1,醋酸浓度5.0％ ～7.5％,戊二醛浓度10％～15％.囊壁固化条件是在pH=4.5～4.8、5℃时固化1h后,然后在pH=8～11、50℃时再固化70 min.在此条件下制备的微胶囊机械强度高且表面光滑,粒径分布在30～80 μm,产率高于90％.用微胶囊制备的显示器件具有良好的显示效果,反射率达到45％～56％,对比度为5～7,响应时间为190～400 ms.     

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。