二乙烯基苯改性煤沥青的中间相转化行为研究

进行了二乙烯基苯(DVB)改性煤沥青的中间相转化行为研究．采用偏光显微镜研究DVB改性煤沥青的光学结构；采用FT-IR和元素分析研究改性煤沥青的热解过程．研究表明，改性煤沥青的光学组织结构显著改善，随交联剂DVB用量的不同，可得到超镶嵌(SM)、广域(D)和小域(SD)三种光学结构；随热解温度的升高，改性沥青中的甲基和亚甲基特征峰的吸收强度逐渐减弱，C／H原子比增加，芳构化程度提高．     

酚醛树脂改性沥青的流变性能及热解动力学研究

以酚醛树脂(PF)为改性剂,在对甲苯磺酸(PTS)的催化作用下,对C/C复合材料基体前驱体中温煤沥青进行了共炭化改性,并对其热解机理进行了研究。首先,对原料煤沥青及共炭化改性后煤沥青的流变性能进行了测试,并采用热重分析(TGDTG)对改性前后煤沥青热解行为进行了研究,计算出了热解动力学参数。结果表明,在催化剂PTS的催化作用下,煤沥青发生了脱甲基反应,并且当PF含量为9%时,共炭化改性的煤沥青其流变曲线与热固性树脂U型曲线相似;根据DTG曲线可以把PF共炭化改性煤沥青的主要热解过程分为两个阶段,由Kissinger法计算得到其活化能和反应级数分别为248.06,15.69kJ·mol~(-1)和1.11、1.14。     

对甲基苯甲醛改性煤沥青的中间相转化行为

进行了对甲基苯甲醛（PMB）改性煤沥青的中间相转化行为的研究，采用FT-IR和元素分析研究改性煤沥青的热解过程；采用偏光显微镜研究PMB改性煤沥青的光学结构，研究表明，改性沥青含有大量的甲基和亚甲基，随热解温度的升高，改性沥青中的甲基和亚甲基特征峰的吸收强度逐渐减弱，C／H原子比增加，芳构化程度提高；此外，改性煤沥青的光学结构为广域（D）组织。     

高性能炭材料生产用煤沥青的研究

研究了软化点在评价煤沥青聚合程度中的作用；描述了热聚合改质过程中煤沥青热解缩聚行为，分析了中温煤沥青热聚合改质过程中各种沥青组分随热聚合温度和热聚合时间的转变规律，探讨了QI组分影响煤沥青热聚合改质的机理，认为原料煤沥青所含原生QI炭微粒促进了热聚合改质过程中煤沥青芳烃分子的聚合；描述了煤沥青的流变性能及其在炭材料实际生产中的意义，研究了中温沥青和改质沥青高温流变性能的差异，探讨了硬脂酸和油酸对煤沥青的改性作用；分析了煤沥青的热解缩聚特征，研究了升温速率对煤沥青热解缩聚的影响。     

二乙烯基苯改性煤沥青的流变行为

研究了二乙烯基苯(DVB)改性煤沥青的流变行为.采用SEM和EDAX对改性前后沥青的形貌和组成进行分析,采用旋转黏度计测试改性沥青的流变性能.研究表明:改性沥青中出现分布均匀的微纤;随着改性沥青中甲苯可溶物含量的减少,其黏性流动活化能变大;改性沥青的剪切速率越高,改性沥青的表现黏度越小.     

呋喃树脂改性煤沥青的机理及热行为研究

以呋喃树脂为改性剂对煤沥青进行了改性，采用傅立叶红外光谱（FT-IR）和扫描电镜（SEM）对呋喃树脂改性煤沥青的机理进行了分析；采用热重和示差扫描量热技术（TG-DSC）对改性前后煤沥青的热解行为进行了分析．实验结果表明，呋喃树脂在煤沥青中起增塑作用，其增塑过程通过四步完成，呋喃树脂与煤沥青发生增塑作用时需要吸收热量；呋喃树脂改性煤沥青的耐热性提高，呋喃树脂对煤沥青的残炭率影响不大．     

升温速率对煤沥青热解缩聚的影响

用TGA对煤沥青的热失重过程进行了研究,分析了煤沥青的热解缩聚特征,并对中温沥青和改质沥青热解缩聚行为进行了比较,研究了升温速率对煤沥青热解缩聚的影响,发现快速升温使煤沥青组份更多地分解逸出,不利于提高煤沥青的结焦值。     

对甲基苯甲醛改性煤沥青的研究

以对甲基苯甲醛 ( 4 - methyl benzaldehyde,简称 4- MB)为改性剂 ,在对甲苯磺酸( PTS)的作用下对煤沥青进行了改性研究 .采用傅立叶红外光谱 ( FT- IR)和核磁共振氢谱 ( 1H-NMR)对煤沥青改性机理进行分析 ;采用扫描电镜 ( SEM)观察改性后煤沥青的形貌 ;采用光学显微镜观察改性沥青热解产物的光学结构 .结果表明 ,对甲基苯甲醛在酸性催化剂的催化作用下与煤沥青发生亲电取代反应 ,改性后煤沥青出现纤维结构 ,改性沥青热解产物的光学组织结构为较好的广域 ( D)结构 .因此 ,改性后的煤沥青有望作为优质的炭材料基体前驱体 .     

超高功率石墨电极生产用炭糊料热解缩聚行为研究

通过TGA对超高功率石墨电极生产用炭糊料的热失重过程进行了研究,分析了炭糊料的热解缩聚特征,并对炭糊料和黏结剂煤沥青的热解缩聚行为进行了对比分析.结果表明,炭糊中煤沥青热解挥发过程不同于单体煤沥青,骨料针状焦的存在使黏结剂煤沥青易发生缩聚反应,从而有利于煤沥青稠环芳烃分子缩聚成焦,从而提高了黏结剂煤沥青的结焦值.     

煤沥青改性后流变性能的变化分析

为了探讨对苯二甲醛(TPA)对煤沥青改性后流变性能的变化,采用旋转黏度计测定了煤沥青及TPA改性的煤沥青的表观黏度,研究了表观黏度与温度的关系;采用示差扫描量热法研究了煤沥青和TPA改性的煤沥青的热行为。结果表明,TPA改性的煤沥青的黏度与温度的关系曲线呈现W型,在200℃～225℃处于低黏流区,表观黏度值200mPa.s～400mPa.s,可以作为浸渍剂煤沥青使用;TPA改性的煤沥青在高于225℃时,表观黏度值迅速上升;TPA改性的煤沥青在低黏度区域具有较低的活化能,这对煤沥青的浸渍工艺有益。     

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。