PP/改性纳米CaCO3复合材料力学性能与断裂形态研究

制备了反应性单体改性纳米CaCO3填充PP复合材料，研究了反应性单体丙烯酸(AA)和苯乙烯(St)在有、无过氧化二异丙苯(DCP)存在下改性纳米CaCO3填充PP复合材料的力学性能，并用扫描电子显微镜(SEM)研究了复合材料弯曲断面的形态。结果表明，PP／改性纳米CaCO3的力学性能优于PP／微米CaCO3的力学性能；在DCP存在下，AA、AA与St混合改性可使PP／纳米CaCO3的拉伸性能和弯曲性能提高，减小拉伸强度随CaCO3含量增加而下降的趋势；并可有效提高纳米CaCO3在基体中的分散性和界面粘结性。     

双单体改性对纳米CaCO3/PP结晶与熔融行为的影响

制备了界面改性纳米CaCO3／PP复合材料，用DSC研究了在有、无过氧化二异丙苯(DCP)存在下，反应单体丙烯酸(AA)及苯乙烯(St)对PP结晶与熔融行为的影响。结果表明：AA改性纳米CaCO3／PP可使结晶温度提高；St改性使纳米CaCO3／PP的结晶温度降低，但在DCP存在下结晶温度反而提高。AA和St双单体改性使纳米CaCO3／PP的结晶温度明显降低，但加有DCP的双单体改性却使纳米CaCO3／PP的结晶温度大幅提高，说明双单体接枝物有促进纳米CaCO3表面成核的作用。     

反应改性纳米CaCO3／PP复合材料的力学性能研究

利用反应性单体甲基丙烯酸（MA）接枝聚丙烯（PP）后，二步法制备了反应改性纳米CaCO3／PP复合材料。研究了复合材料的力学性能，并用扫描电子显微镜（SEM）观察了复合材料经液氮冷却脆断后断面的形态。结果表明，甲基丙烯酸接枝聚丙烯（MAPP）加入后与CaCO3反应使MAPP与纳米CaCO3微聚体之间产生离子键作用，使纳米／PP复合材料的力学性能得到大幅提升，对冲击性能的改善尤为明显。充分控制的MA反应量比单独依靠MAPP增容能够更为有效地提高纳米CaCO3的分散性和界面黏结性。     

反应单体改性纳米CaCO3／PP母料的制备和性质研究

用溶液法制备了反应性单体改性PP包覆纳米CaCO3母料，用IR、DSC和TGA等方法研究了母料中的化学作用、结晶与熔融行为、热稳定性和表面性质等。研究结果表明反应性单体改性PP形成接枝物包覆纳米CaCO3，纳米CaCO3的质量分数高达80％。不同单体对PP结晶温度有不同的影响结晶温度高低顺序为甲基丙烯酸甲酯〉丙烯酸甲酯〉丙烯酸丁酯-丙烯酸与苯乙烯混合物〉无单体-马来酸酐-丙烯酸〉苯乙烯。单体改性使母料接触角进一步提高。     

不同形态纳米级CaCO3改性PP研究

研究了不同形态纳米级CaCO3改性PP复合材料的力学性能及其对PP球晶形态的影响。结果表明，纳米级CaCO3形态不同，复合材料力学性能不一样，立方形纳米级CaCO3有利于改善复合材料的冲击性能，而纤维状纳米级CaCO3则能明显改善材料的拉伸性能。纳米级CaCO3能使PP球晶明显的细化．并能促进β晶型的生成。     

反应单体改性纳米CaCO3/PP母料的制备和性质研究

用溶液法制备了反应性单体改性PP包覆纳米CaC03母料，用IR、DSC和TGA等方法研究了母料中的化学作用、结晶与熔融行为、热稳定性和表面性质等。研究结果表明：反应性单体改性PP形成接枝物包覆纳米CaCO3，纳米CaCO3的质量分数高达80％。不同单体对PP结晶温度有不同的影响，结晶温度高低顺序为甲基丙烯酸甲酯〉丙烯酸甲酯〉丙烯酸丁酯。丙烯酸与苯乙烯混合物〉无单体。马来酸酐。丙烯酸〉苯乙烯。单体改性使母料接触角进一步提高。     

NBR改性PVC/nano-CaCO3复合材料的研究

将NBR、PVC及纳米CaCO3熔融复合以增韧PVC/纳米CaCO3复合材料.研究了复合材料的力学性能、流变性能、热性能及微观形态.结果显示NBR对PVC/纳米CaCO3具有增韧效果,材料的断裂伸长率明显增大,PVC/NBR/nano-CaCO3为100/12/8时冲击强度最大,达到了30kJ/m2,比对应的单独纳米CaCO3增韧的PVC提高了大约27%.NBR能降低PVC/CaCO3复合材料的熔体黏度,复合材料加工性能改善.同时NBR的加入使得复合材料的玻璃化转变温度降低,热稳定性变差.扫描电镜照片显示,PVC/NBR/nano-CaCO3为100/12/8时,NBR的加入提高了CaCO3的纳米级分散程度,冲击断面出现了纤维状形变,使得复合材料的冲击强度提高.     

纳米级CaCO3改性PP的研制

采用纳米级CaCO3改性PP，同时考察了POE(乙烯辛烯共聚物)对该改性体系力学性能的影响。结果表明采用纳米级CaCO3和POE改性PP能明显提高PP的力学性能，而且该复合材料在生产中具有实际应用价值。     

聚丙烯/纳米CaCO3复合材料的结晶行为研究

用超重力法制备的纳米CaCO3和PP熔融共混制备了PP/CaCO3复合材料,并对PP/CaCO3复合材料的结晶行为进行了详细研究。差示扫描量热分析表明,纳米CaCO3粒子的加入加快了PP的结晶速率,缩短了半结晶时间,130℃时含15份纳米CaCO3的PP/CaCO3复合材料的半结晶时间比纯PP的减少了8.92 min;结晶度有轻微下降,结晶温度为126.5 ℃时纯PP的结晶度为44.33 %,含15份纳米CaCO3的PP/CaCO3复合材料的结晶度为35.9 %。动力学研究数据表明,等温结晶过程符合Avrami方程,PP/CaCO3的n和k值都大于纯PP的;利用偏光显微镜观察了PP/CaCO3复合材料的结晶形貌及结晶生长过程,纳米CaCO3粒子的加入使球晶数量明显增多,意味着CaCO3起到了结晶成核剂的作用。     

聚丙烯/水相法改性纳米碳酸钙复合材料的结构与性能

用三官能团的有机改性剂对纳米碳酸钙进行表面改性，填充到聚丙烯中，制得PP／纳米CaCO3复合材料，同时对复合材料的力学性能、微观形态以及热性能进行研究。结果表明：PP／改性纳米CaCO3复合材料的力学性能及热性能都有较大幅度的改善。改性剂与纳米CaCO3形成化学结合，改性纳米CaCO3对PP有异相成核的作用，能诱导口晶型PP的产生，在提高复合材料强度的同时，使韧性明显提高。     

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。