双邻苯二甲腈改性环氧及其玻纤复合材料制备

采用双邻苯二甲腈树脂(BAPh)对环氧树脂E-44(EP)进行改性,同时制备了BAPh/EP/玻纤复合材料。采用示差扫描量热仪,热重分析,力学性能测试及氧指数仪研究了改性树脂的热性能、力学性能及阻燃性能,并对BAPh/EP/玻纤复合材料的力学性能进行了表征。结果表明,当BAPh质量分数达到50%时,改性树脂固化物在空气中的起始分解温度达到377.6℃,比纯环氧提高74.3℃,氧指数达到34.5%,复合材料的弯曲性能指标达到最大,添加双邻苯二甲腈后环氧树脂的耐热性、力学性能和阻燃性能得到了明显改善。     

环氧树脂/纳米纤维素复合材料的制备与性能研究

以木粉为原料制备纳米纤维素（CNF）,经甲基丙烯酸缩水甘油酯（GMA）改性后采用溶液共混法与环氧树脂（EP）复合,制得EP/CNF⁃GMA复合材料;通过对EP/CNF、EP/CNF⁃GMA复合材料力学性能、透光性能、亲水性、热稳定性和微观结构的表征,研究了CNF和GMA含量对复合材料性能的影响及其机理。结果表明,EP/CNF复合材料的拉伸强度、断裂伸长率、透光率随CNF含量的增大呈先增后减的变化趋势,亲水性随CNF含量的增大而增大;CNF含量为0.6 %（质量分数,下同）时,EP/CNF复合材料性能最优,拉伸强度为32.166 MPa,断裂伸长率为20.995 %,600 nm处透光率为79.8 %,接触角为77.34°。经GMA改性后,CNF与EP的相容性得到了改善,提升了EP/CNF复合材料的力学性能和热稳定性;随GMA含量的增加,EP/CNF⁃GMA复合材料的拉伸强度、断裂伸长率、透光率和亲水性均发生变化;GMA含量为4.8 %时EP/CNF⁃GMA复合材料性能最佳,拉伸强度为57.933 MPa,断裂伸长率为18.762 %,600 nm处透光率为86.3 %,接触角为81.42 °。     

发散法接枝聚酰胺-胺改性碳纤维织物及其应用研究

采用发散法,以乙二胺(EDA)为引发核,与丙烯酸甲酯(MA)通过迈克尔加成和酰胺化反应将1.0代聚酰胺-胺(1.0 G PMMAM)接枝到碳纤维织物(CFF)表面,同时将1.0 G PMMAM作为双酚A型环氧树脂(EP)的固化剂,制备了接枝改性CFF/EP复合材料,分析了改性CFF的表面结构及改性前后CFF/EP复合材料的力学性能。结果表明:通过迈克尔加成和酰胺化反应,1.0 G PAMAM被成功地接枝在CFF表面;接枝改性后CFF表面粗糙度增加,沟壑变得更密,且其类石墨的有序结构遭到破坏,无序性增加;接枝改性CFF/EP复合材料的弯曲强度、剪切强度和冲击强度较未改性CFF/EP复合材料分别提高了102%,99%和30%。     

苎麻织物增强不饱和聚酯树脂复合材料成型工艺及其阻燃性能

为了探究苎麻织物增强不饱和聚酯(UP)树脂复合材料的模压成型工艺以及提升其阻燃性能,通过差示扫描量热对树脂固化工艺进行研究,通过对苎麻织物克重、模压压力以及织物铺层层数进行探究,得出复合材料的最佳制备工艺;利用植酸(PA)对苎麻织物进行阻燃改性,研究PA含量对复合材料阻燃及其力学性能的影响.结果表明,UP的最佳固化工艺...     

超支化聚合物接枝纳米TiO_2/环氧树脂复合材料的制备与表征

利用偶联剂KH-550和超支化聚(胺-酯)(HBP)对纳米TiO2进行改性,并制备了纳米TiO2/环氧树脂(EP)复合材料。对复合材料的结构、力学性能、加工性能以及热性能进行了研究。研究结果表明,HBP接枝改性纳米TiO2(TiO2-g-HBP)的引入可明显提高复合材料的力学性能、热性能及加工性能;当w(TiO2-g-HBP)=1%时,复合材料的力学性能最好,其冲击强度和弯曲强度比纯EP分别提高了135.51%和22.98%;扫描电镜(SEM)结果显示,TiO2-g-HBP/EP复合材料由脆性断裂转变为韧性断裂。     

膨胀阻燃环氧树脂/有机化凹凸棒土复合材料的制备及性能研究

考察了不同膨胀型阻燃剂(IFR)添加量对环氧树脂(EP)阻燃性能的影响,以及有机化凹凸棒土(OAT)对膨胀阻燃环氧树脂复合材料性能的影响,最后对复合材料的增韧机理及阻燃机理进行了简要分析。结果表明,在环氧树脂中加入25%的IFR,可使复合材料的氧指数(LOI)达到30%,并通过UL94 V-0级测试,但拉伸性能有所降低;在膨胀阻燃环氧树脂体系中,适量添加3%的OAT能使复合材料的力学性能有所提高,对氧指数未见协同改善效果,但都通过了UL94垂直燃烧测试。     

无卤阻燃型聚丙烯的制备及性能研究

利用双螺杆挤出机挤出制备了超细Mg(OH)2改性阻燃聚丙烯(PP)复合材料,研究了Mg(OH)2、复合增容剂的用量对复合材料力学性能、阻燃性能的影响.结果表明,Mg(OH)2经硬脂酸表面改性后,其在PP中的分散性及与PP的界面相容性明显得到改善,当Mg(OH)2用量为90份时,材料的氧指数达到27.5%;(乙烯/辛烯)共聚物接枝马来酸酐/(乙烯/丙烯/二烯)共聚物接枝马来酸酐复合增容剂能明显改善材料的力学性能和阻燃性能,当复合增容剂用量为15份时,材料的断裂伸长率达到141.06%,缺口冲击强度达到22.24 kJ/m2,拉伸强度达到18.51MPa,氧指数增至28.0%.     

纳米改性氢氧化铝/尼龙66复合材料的制备及其力学性能的研究

将自制的纳米改性氢氧化铝(CG-ATH),用不同表面改性剂进行改性,以不同比例添加到PA66中,制得复合材料.该种复合材料的阻燃性能、拉伸性能和冲击性能都有所改善,纯尼龙66与添加40份CG-ATH/PA66复合材料相比较,极限氧指数(LOI)从25提高到29,拉伸性能提高了31%,冲击强度提高了8.6%.但是,随着CG-ATH添加量的增加,复合材料的阻燃性能和力学性能均逐渐变差.     

多壁碳纳米管表面羧基化及其阻燃ABS的性能

采用硝酸氧化/低温等离子处理两步法,将多壁碳纳米管(MWCNTs)羧基化(MWCNTs-COOH),以改善其在ABS基体中的分散性。通过熔融共混的方法制备不同组分ABS/MWCNTs-COOH复合材料。利用红外、拉曼分析、扫描电镜对改性修饰后MWCNTs结构进行研究;利用扫描电镜、热重分析、极限氧指数、残炭分析、力学性能测试对ABS/MWCNTs-COOH复合材料分散性、热性能、阻燃性能、力学性能进行研究。实验结果表明,MWCNTs羧基化改性后提高了在ABS基体材料中的分散性;当MWCNTs-COOH含量为1%时,复合材料初始分解温度和最大分解温度分别提高了22.69℃和27.90℃,热稳定性提高,同时复合材料力学性能也得到改善,拉伸强度提高了18.3%;极限氧指数和残炭测试表明,MWCNTs-COOH加入提高了复合材料的极限氧指数,MWCNTs-COOH在复合材料燃烧过程中,会在材料表面形成网络状炭层,提高复合材料的阻燃性能。     

阻燃交联聚乳酸/苎麻复合材料的制备及性能

采用9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)对直接缩聚法制备的交联聚乳酸进行阻燃改性,并将改性交联的聚乳酸与苎麻纤维通过涂布和热压成型制备了阻燃交联聚乳酸/苎麻纤维复合材料。并研究了DOPO含量对力学性能、热稳定性和阻燃性能的影响,实验结果表明,随着DOPO质量分数的增大,复合材料的力学性能均有所下降,当DOPO含量为7%时,与未添加DOPO相比,拉伸强度降低了22.8%,拉伸模量降低了11.6%,断裂伸长率降低了6.07%,弯曲强度降低了22.7%,冲击强度降低了39.3%。但是,DOPO的引入起到了阻碍热分解、促进成炭的作用,改善了交联聚乳酸/苎麻纤维复合材料的热稳定性,另外,DOPO的加入也能提高复合材料的极限氧指数,提高复合体系的阻燃性能。     

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。