酸化处理碳纳米管改性双马来亚酰胺树脂性能的研究

采用浓硫酸和浓硝酸混合酸（体积比3：1）处理多壁碳纳米管，使其表面产生羟基和羧基，并通过SEM、红外、热重等进行表征；将酸化后的CNTs加入到双马来亚酰胺树脂休系中，研究不同含量的CNTs对体系力学性能、热性能的影响。结果表明，CNTs的表面产生了羟基和羧基，将其加入到双马来亚酰胺树脂中进行改性，提高了其与基休的结合性与分散性；随着CNTs用量的增加，体系的力学性能和耐热性能有先提高后降低的趋势；当CNTs质量分数为1.5％时，冲击强度达到最火值，比纯BMI提高53．2％。     

碳纳米管改性双马来酰亚胺树脂体系的性能

采用原位聚合法将碳纳米管(CNTs)与双马来酰亚胺(BMI)复合制备BMI/CNTs复合材料,通过差示扫描量热仪分析了CNTs的用量对BMI树脂体系反应活性的影响。研究了CNTs的用量对复合材料静态力学性能、动态力学性能及耐湿热老化性能的影响。结果表明,随着CNTs用量的增多,体系的反应活性呈降低趋势,而力学性能、耐湿热性能均有所提高;当CNTs质量分数为1.5%时,复合材料的冲击强度和弯曲强度分别提高了近63.1%和10%,其后随CNTs用量的增大均略有下降。     

处理方法对碳纳米管织构性质及负载Pd-Pt催化剂萘加氢反应活性的影响

采用酸性KMnO4溶液、浓HNO3／H2SO4混酸、中性H202溶液和高温熔融KOH分别对碳纳米管（CNTs）进行了氧化处理，用氮气物理吸附、高分辨透射电镜（HRTEM）、傅立叶变换红外光谱（FTIR）、化学滴定和X射线衍射（XRD）对处理后CNTs的表面性质和体相结构进行了研究，考察了其处理前后的变化及其负载的Pd—Pt催化剂在萘加氢为四氢萘反应过程中的的活性。结果表明：KMnO4和混酸处理后，CNTs表面上形成了大量含氧基团，H2O2处理时含氧基团量生成量则较少，而KOH处理后生成的含氧基团量很少，但CNTs比表面积显著提高，同时也使其体相结构破坏。CNTs负载的Pd-Pt催化剂上萘加氢反应的活性随表面羧基类基团含量的升高而增加。     

超电容器碳纳米管与钼复合电极材料的研究

以碳纳米管（CNTs）为基体材料，用浓硝酸回流处理碳纳米管，TEM（透射电子显微镜）研究表明碳纳米管的端帽被部分打开，通过液相反应对碳纳米管进行表面改性，制备CNTs／Mo复合电极材料，复合电极使电解液和导电材料的接触面积增大，使电极反应的有效表面积增大，反应场所有所增加，从而提高电极电化学反应的活性。基于此复合材料的超电容器具有高比电容、高稳定性、良好的可逆性和长寿命等特点。循环伏安结果表明：CNTs/Mo复合电极的比电容比纯CNTs电极要高出20％。     

碳纳米管改性双马来酰亚胺/碳纤维复合材料力学性能研究

采用碳纳米管（CNTs）改性双马来酰亚胺（BMI）／碳纤维（CF）复合材料,通过X射线衍射（XRD）、红外光谱（FTIR）和透射电镜（TEM）等手段分析了CNTs表面处理工艺对其结构的影响。分析研究了CNTs加入量对复合材料力学性能的影响。结果表明,随着CNTs的加入,体系的力学性能得到了不同程度的提高,当CNTs加入的质量分数为1％时,体系的层间剪切强度和弯曲强度分别提高51、4％和10．1％。     

PA6／CNT复合材料的动态机械性能和增强机理分析

采用三种处理方法得到了不同表面性质的碳纳米管，与尼龙6共混制备了PA6／CNTs复合材料。考察了复合材料的动态机械性能。研究发现，碳纳米管的加入提高了尼龙6的储能模量和损耗模量，碳纳米管表面的性质决定了对复合材料动态机械性能的改变程度。经过高温高压剧烈反应的CNTs3#会断裂为尺寸较小的碳管，小尺寸碳管的成核作用使得复合材料结晶度提高，以及CNTs3#表面接枝的一NH2和未反应的-COOH，会造成尼龙6大分子链段的交错缠绕，因而PA6／CNTs3#的储能模量和损耗模量最大。混酸和加热搅拌条件下氧化CNTs1#含有比单纯浓硝酸氧化的CNTs2#更多的-COOH，所以PA6／CNTs 1#的储存模量和损耗模量大于PA6／CNTs2#。     

改性碳纳米管与锶铁氧体复合材料的制备及性能研究

利用H2O2和浓H2SO4的混合溶液、浓硝酸分别对碳纳米管（CNTs）进行改性处理,并用改性CNTs与一定量的硝酸铁、硝酸锶反应．制备出了改性碳纳米管与锶铁氧体复合材料。利用IR、VSM、TEM等检测了材料的性能。结果表明,改性后的碳纳米管表面主要引入了羟基、羰基,其水溶性明显增强;复合材料的磁性能较好,但加入CNTs后,复合材料的矫顽力呈降低趋势,且随着CNTs含量的增加,矫顽力降低越大。空白实验表明,锶铁氧体的粒径在20nm左右,这也是复合材料磁性能较高的主要原因。     

二元胺型苯并噁嗪/双马来酰亚胺共混树脂及其玻璃布增强的层压板

苯并噁嗪(BZ)和双马来酰亚胺(BMI)按照不同的配比进行共混固化。用FTIR、DSC、凝胶化时间、DMA、TGA、万能电子拉力机分别研究了BZ/BMI共混体系的固化行为以及BZ/BMI固化树脂的热性能和剪切强度等。结果表明BZ和BMI除了发生均聚反应,还发生苯并噁嗪开环生成的酚羟基和双马来酰亚胺的双键生成醚键的反应。BZ和BMI共混后,固化温度比各自的固化温度都低。BMI的加入提高了共混树脂的热性能,BZ/BMI固化树脂的T_g达289℃,T_d5达387℃,T_d10达422℃,800℃的残炭率达55.3%。另外,BMI的加入提高了BZ/BMI固化树脂的剪切强度,当BMI的含量为60％时,BZ/BMI固化树脂的剪切强度为12.44 MPa。进一步,制备了玻璃布增强的BZ/BMI层压板,并对其力学性能和断面形貌进行了研究。结果表明,当BMI用量为40%时,BZ/BMI层压板的拉伸强度、弯曲强度、冲击强度分别达394 MPa、490 MPa、160 kJ·m^-2。     

晶须改性二苯甲烷型双马来酰亚胺树脂体系的研究

以硼酸铝晶须、钛酸钾晶须为增强剂，以N，N′-二胺基二苯甲烷型双马来酰亚胺(BMI)／O，O′-二烯丙基双酚A(BA)体系作为基体，采用浇注成型工艺制备了晶须增强二苯甲烷型双马来酰亚胺树脂基复合材料。研究了晶须对树脂体系凝胶特性的影响，晶须对体系固化反应性的影响；晶须的种类、表面处理方法、含量对树脂体系力学性能和热性能的影响；树脂体系的固化工艺材料对性能的影响。结果表明，晶须对树脂体系固化工艺影响不大；硼酸铝晶须增强效果优于钛酸钾晶须；偶联剂以丙酮作溶剂处理的效果优于乙醇水溶液，酸化溶剂的效果更好；晶须可明显改善体系的力学性能和耐热性，在晶须添加量为15％左右时，所得体系的综合性能较好；改进的固化工艺有助于树脂体系性能的改善。在本研究中，弯曲强度最大提高了约18％，热变形温度最大提高了12％。     

POSS改性BMI树脂固化动力学及固化工艺研究

以双马来酰亚胺(BMI)、二烯丙基双酚A(BA)和七苯基倍半硅氧烷三硅醇(POSS-triol)为原料,采用非等温差示扫描量热(DSC)法研究了BMI/BA/POSS-triol体系的固化反应过程。运用Kissinger极值法、Crane法、Flynn-Wall-Ozawa(FWO)等转化率法和T-β(温度-升温速率)外推法确定了改性树脂体系的固化反应动力学参数和固化工艺参数。结果表明:改性树脂体系的固化反应活化能和反应级数(接近于1)均随POSS-triol用量增加而变化不大,说明POSS-triol的加入并没有明显改变BMI/BA体系的固化反应机理;改性树脂体系的凝胶温度为175.7℃,固化温度为226.9℃,后处理温度为271.7℃。     

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。