GC-MS法测定聚丙烯(PP)熔喷专用料中二叔丁基过氧化物(DTBP)的残留量

建立气相色谱-质谱法测定聚丙烯(PP)熔喷专用料中的二叔丁基过氧化物(DTBP)残留量的方法。试样用四氢呋喃提取、超声波萃取，提取液净化后用气质联用仪分析。二叔丁基过氧化物(DTBP)的平均回收率为98.62%,6次平行测定的RSD值≤2.25%，方法测定低限为1 mg/kg，满足聚丙烯(PP)熔喷专用料中的二叔丁基过氧化物(DTBP)残留量的检测。     

三甘醇双[3-(3′,5′-二叔丁基-4′-羟基苯基)丙酸]酯的合成与表征

以3—(3′,5′—二叔丁基—4′—羟基苯基)丙酸甲酯和三甘醇为原料,有机锡为催化剂,通过酯交换法在甲苯作溶剂的条件下合成了三甘醇双[3—(3′,5′—二叔丁基—4′—羟基苯基)丙酸]酯：通过实验考察了反应温度、催化剂及催化剂用量、反应时间及物料配比等因素对反应的影响。结果表明,最佳反应条件为：反应温度120～125℃,催化剂为有机锡,催化剂用量0．25g,反应时间3．5h,3—(3′,5′—二叔丁基—4′—羟基苯基)丙酸甲酯与三甘醇物质的量比为2．10：1,在此条件下,产物收率在94％以上,产品熔点为106-107℃,通过元素分析、红外光谱分析、核磁氢谱对产品结构进行了表征。     

二叔丁基过氧化物的热分解动力学分析及T D24的获取

为研究二叔丁基过氧化物-甲苯体系的热分解特性及其热危险性,采用质量分数20％二叔丁基过氧化物为研究对象,利用绝热加速量热仪(ARC)探究不同升温速率和样品质量对其热分解行为的影响;并分别利用Townsend方法和外推法获取了混合体系达到最大反应速率所需的时间为24 h对应的温度T D24,并分析对比了两种方法计算结果的...     

二叔丁基过氧化物含量测定方法的改进

二叔丁基过氧化物是高分子化学中常用的引发剂之一。其纯度对聚合反应的影响很大,因此在生产过程中需准确测定其含量以控制产品质量。含量测定常用的碘量法,是基于过氧化物与碘离子的反应:     

抗氧剂1076的合成研究

介绍了以2,6－二叔丁基苯酚,丙烯酸甲酯进行加成反应制取β-（3,5－二叔丁基－4－羟基苯基）丙酸甲酯,再由β-（3,5－二叔丁基－4－羟基苯基）丙酸甲酯和十八碳醇在催化剂的作用下进行酯交换合成抗氧剂1076的方法,并确定了最佳的工艺条件,且产品收率大于92％。     

2，6—二叔丁基对苯醌合成工艺研究

研究了2,6－二叔丁基对苯醌的合成工艺,选择了最佳合成方法,即催化分子氧氧化法,该法以2,6－二叔丁基苯酚和氧气为原料,采用自制催化剂,进行气液相氧化,通过多次对比实验,确定了最佳催化剂用量和产品提纯方法,产品收率为70％,纯度大于99．5％。     

抗氧剂1076的合成改进研究

对以2，6－二叔丁基苯酚、丙烯酸甲酯和十八碳醇为主要原料合成抗氧剂1076的原工艺条件进行改进，使总收率达80％以上。     

高固体分低黏度羟基丙烯酸树脂的制备

以丙烯酸(AA)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、叔碳酸缩水甘油酯(E-10P)、丙烯酸羟丙酯(HPA)为单体,以二叔丁基过氧化物(DTBP)为引发剂,采用溶液聚合法合成了高固体分低黏度的羟基丙烯酸树脂。通过研究引发剂用量、E-10P用量以及反应温度等反应条件对树脂固含量和黏度等性能的影响,确立了合成羟基丙烯酸树脂的最佳配方:引发剂二叔丁基过氧化物用量为2%,E-10P用量为15%,反应温度为150℃左右。在上述配方和工艺条件下制得的树脂为无色透明液体,固体分高达75%,黏度仅为1 350 mPa·s。     

己二醇双[3-(3,5-二叔丁基-4-羟基苯基)]丙酸酯的合成

以3－（3，5－二叔丁基－4－羟基苯基）丙酸甲酯（简称3，5－甲酯）与1，6－己二醇为原料，有机锡为催化剂，在无溶剂的条件下合成了己二醇双[3-(3,5-二频丁基－4－羟基苯基）]丙酸酯。通过实验考察了反应温度、催化剂用量、反应时间及物料配比等因素的影响。结果表明，最佳的反应条件是反应温度120－140℃，催化剂用量为反应物总质量的1．2％左右，反应时间4h,3,5-l甲酯与1，6－己二醇摩尔比为2．05：1。在此条件下，收率在95％以上，并通过元素分析、红外光谱分析、核磁氢谱对产品进行了结构表征。     

3,5-二叔丁基-4-羟基苯甲酸的合成研究

以N，N－二甲基乙酰胺为溶剂的碱性环境中，常压下通过CO2与2，6－二叔丁基苯酚反应来制备3，5－二叔丁基－4－羟在苯甲酸。     

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。