MMA/N-对甲苯基马来酰亚胺乳液共聚的研究

通过乳液共聚得到N－对甲苯基马来酰亚胺（NPTMI），甲基丙烯酸甲酯（MMA）的二元共聚物，用扭辫分析，热重分析和维卡软化点测定仪研究了不同NPTMI含量对共聚物热性能的影响，以及共聚物的力学性能，流变性能，研究结果表明，共聚物初始分解温度（Tini)，失重50％时的温度，玻璃化转变温度（Tg)及维卡软化点（TViout)都随NPTMI的含量增加而提高，当NPTMI含量为15％时，Tg提高14．1℃，Tini提高23．2℃，TVicut提高8．9℃，工聚物熔体呈假塑性流体，同时共聚物熔体非牛顿指数随NPTMI含量的增加而增大。     

N-对甲苯基马来酰亚胺与丙烯腈共聚动力学及共聚物的热性能

以AIBN为引发剂,研究了不同配比的丙烯腈(AN)与N-对甲苯基马来酰亚胺(NPTMI)在80℃的自由基溶液共聚合 ,并根据FTIR谱图确证了共聚物的存在。根据元素分析的结果,用FR法得到竞聚率的值rAN=0.57,rNPTMI=1.47。用GPC测定了共聚物的分子量并分别用DSC、TGA对其玻璃化温度和热失重情况进行了研究,发现共聚物具有良好的热性能。     

N-环己基马来酰亚胺／甲基丙烯酸甲酯／苯乙烯乳液共聚物与PVC共混的研究

通过乳液共聚合得到N-环己基马来酰亚胺(ChMI)、甲基丙烯酸甲酯(MMA)、苯乙烯(St)的三元共聚物(ECMS)，用共聚物作耐热改性剂与PVC共混，用TBA和TGA研究了共聚物含量对共混物热性能、力学性能、流变性能及维卡软化点的影响。结果表明随三元共聚物含量的增加，共混物的玻璃化温度及维卡软化点逐渐上升；PVC第一阶段降解完毕。后平台区残留量逐渐上升；拉伸强度提高，冲击强度下降；熔体表观粘度增加，呈假塑性流体。     

氯化聚氯乙烯/聚氯乙烯/抗冲击改性剂共混对埋地式高压电力电缆套管的维卡软化温度及力学性能的影响

研究了氯化聚氯乙烯(PVC-C)/聚氯乙烯(PVC)/抗冲击改性剂(CPE/ACR)共混体系对埋地式高压电力电缆PVC-C护套管的维卡软化温度和力学性能的影响。结果表明,在基础配方不变的情况下,PVC-C/PVC共混体系中,随着PVC-C含量的增加,管材的维卡软化温度提高,抗冲击性能下降;在PVC-C/PVC配比不变的情况下,冲击改性剂CPE(氯化聚乙烯)和抗冲ACR(丙烯酸酯类共聚物)的加入份数的提高,管材的抗冲击性能提高,维卡软化温度降低。     

多单体固相接枝共聚物对废聚丙烯/稻糠复合体系结构与性能的影响

用固相接枝法接枝合成了聚丙烯(PP)与甲基丙烯酸甲酯(MMA)／马来酸酐(MAH)／丙烯酸丁酯(BA)的多单体接枝共聚物(GPP)，将其应用于废聚丙烯(RPP)／稻糠(RC)复合体系，研究了接枝共聚物对体系的力学性能、微观形态、热性能的影响。结果表明，在RPP／RC复合体系中加入固相接枝共聚物，可有效提高复合材料的拉伸强度、弯曲强度、弯曲模量和维卡软化点。     

纳米ZnO／ABS复合材料的制备及性能研究

制备了改性纳米ZnO／丙烯腈-丁二烯-苯乙烯共聚物复合材料，研究改性纳米ZnO用量对复合材料维卡软化温度及紫外线老化前后力学性能的影响。结果表明：适量添加改性纳米ZnO既可有效提高ABS复合材料的维卡软化温度及各种力学性能，又可赋予复合材料优良的耐老化性能。改性纳米ZnO用量为3％时，ABS复合材料的维卡软化温度达102℃，比纯ABS树N（98．7℃）提高3．2℃；紫外线老化前后复合材料的拉伸强度较纯ABS树脂分别提高37．4％和44．6％、断裂伸长率提高0．9％和357％、硬度提高45．4％和29％、缺口冲击强度提高13.8％和44．7％、无缺口冲击强度提高12．4％和44.4％。     

甲基丙烯酸甲酯-N-环己基马来酰亚胺-丙烯腈共聚物的合成及其与PVC共混的研究

通过悬浮聚合得到了甲基丙烯酸甲酯-N-环己基马来酰亚胺-丙烯腈三元共聚物，将其作为耐热改性剂与PVC共混。研究了单体配比对共聚物的玻璃化转变温度和溶度参数的影响及共聚物含量对共混物热性能和力学性能的影响。结果表明，共聚物的玻璃化转变温度随N-环己基马来酰亚胺（CHMI）用量的增加明显提高，随丙烯腈（AN）用量的增加而降低；溶度参数随CHMI用量的增加上升，随AN用量的增加而下降。将此共聚物与PVC共混，当其用量为PVC的40％（质量分数，下同）时，PVC的维卡软化点提高了20℃。     

PA6/长玻纤/氯化钙复合材料结构与性能研究

采用熔融挤出工艺制备了尼龙(PA)6/长玻璃纤维(LGF)/氯化钙复合材料;研究了LGF含量对复合材料力学性能、维卡软化点、结晶性能的影响.结果表明,LGF的加入可以提高PA6的结晶速率和结晶度;当LGF质量分数为30％时结晶度最大,达到33.1％.随着LGF含量的增加,复合材料的力学性能及维卡软化点温度均大幅提高,当...     

SMA-g-VC共聚物的合成与性能

通过在氯乙烯单体悬浮聚合过程中加入苯乙烯-马来酸酐共聚物(SMA),合成苯乙烯-马来酸酐接枝氯乙烯共聚物(SMA-g-VC),使其耐热性能、力学性能以及流变性能高于PVC/SMA共混体系,克服了共混体系冲击强度大幅下降的缺点,通过拉伸试验机、红外、旋转流变、维卡软化点等对其力学性能、结构特征、流变性、耐热性能与PVC/SMA共混体系对比分析,结果表明:SMA-g-VC共聚物在1 640 cm~(-1)以及3 236 cm~(-1)处出现新的红外吸收峰,拉伸强度、断裂伸长率、冲击强度、维卡软化点均比共混体系高,且其加工流变性能更好、塑化时间更短。     

PP/ABS-g-MAH/SCF复合材料的制备及性能表征

采用熔融共混法制备了聚丙烯(PP)/马来酸酐接枝丙烯腈-丁二烯-苯乙烯共聚物(ABS-g-MAH)/短碳纤维(SCF)复合材料,并利用万能电子试验机、冲击试验机、维卡软化和负荷热变形温度测试仪、热重分析仪以及熔体流动速率仪分别研究了其力学性能、热学性能及流动性能。力学性能测试表明:以PP-g-MAH作为增容剂,适量的加入SCF(5%~10%),复合材料的力学性能提升明显。维卡软化温度实验结果显示:SCF的加入提高了复合材料的维卡软化温度。热重分析表明:随着体系内SCF含量的逐渐增加,复合材料失重5%时的温度(T_(5%))有逐渐上升的趋势,说明SCF的加入在一定程度上提高了复合体系的热稳定性。熔体流动速率分析表明:随着SCF含量的不断增加,复合材料的熔体流动速率下降明显,流动性能受到抑制。     

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。