纳米CaCO_3高填充ABS复合材料的制备

分别采用苯乙烯-丁二烯-苯乙烯共聚物(SBS)和乙烯-乙酸乙烯共聚物(EVA)作增韧剂,利用熔融挤出法制备纳米CaCO_3高填充丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)/CaCO_3复合材料,研究了纳米CaCO_3填充量和增韧剂种类对ABS/CaCO_3复合材料力学性能和熔体流动速率的影响。结果表明:SBS对ABS/CaCO_3复合材料的增韧效果优于EVA;当ABS用量为100.0 phr、纳米CaCO_3填充量为25.0 phr、SBS用量为5.0 phr时,可得到力学性能符合GB/T 10009—1988要求的ABS/CaCO_3复合材料;当SBS和EVA用量较低时,SBS更能明显提高ABS/CaCO_3复合材料的熔体流动速率。     

纳米CaCO_3-AES复合材料制备和性能研究

分别以氯化聚乙烯(CPE)和苯乙烯-丁二烯-苯乙烯共聚物(SBS)作为增韧剂,利用熔融共混挤出法制备了纳米CaCO_3填充丙烯腈-三元乙丙橡胶-苯乙烯接枝共聚物(AES)复合材料,研究了纳米CaCO_3填充量和增韧剂种类对纳米CaCO_3-AES复合材料力学性能和热氧老化性能的影响。结果表明,适量的纳米CaCO_3加入到AES树脂中,可以与AES基体充分吸附、键合,提高AES树脂的力学性能;以CPE和SBS作为CaCO_3-AES复合材料增韧剂,添加质量分数12%的纳米CaCO_3的CaCO_3-AES复合材料,分别用质量分数12%的CPE、SBS改性复合材料,与未改性AES树脂相比,其拉伸强度相当,弯曲强度提高了10%,抗冲强度提高了20%;CPE增韧CaCO_3-AES的抗老化性能明显优于同比例的SBS增韧CaCO_3-AES。     

阻燃ABS的增韧研究

分别以苯乙烯-丁二烯-苯乙烯共聚物(SBS)、乙烯-1-辛烯共聚物(POE)、三元乙丙橡胶(EPDM)为增韧剂,研究了它们对阻燃丙烯腈-丁二烯-苯乙烯共聚物(ABS)复合材料力学性能和阻燃性能的影响。结果表明:以SBS为增韧剂所得复合材料的综合性能优于以POE或EPDM为增韧剂所得复合材料;随SBS用量的增大,复合材料的冲击强度提高,当SBS用量为15%时,其冲击强度达到15.91kJ/m2,较未经增韧改性复合材料的冲击强度提高了9.99kJ/m2;并且SBS的加入不会对复合材料的阻燃性能产生不利影响。     

PA6/PA6-g-MAH/云母复合材料的增韧研究

分别以乙烯-乙酸乙烯共聚物(EVA)、乙烯-1-辛烯共聚物(POE)、苯乙烯-丁二烯-苯乙烯共聚物(SBS)为增韧剂,研究了它们对聚酰胺6(PA6)/聚酰胺6接枝马来酸酐(PA6-g-MAH)/云母复合材料力学性能的影响。结果表明:以EVA为增韧剂所得复合材料的力学性能优于以POE或SBS为增韧剂所得复合材料;复合材料的冲击强度随EVA用量的增大而上升,当EVA用量为10%时,其冲击强度达到19.01 kJ/m2,较未经增韧改性的复合材料提高了5.29 kJ/m2;但复合材料的拉伸强度和弯曲模量均随增韧剂用量的增大而降低。     

氯化聚乙烯对ABS/PVC合金性能的影响

以氯化聚乙烯(CPE)为增韧剂,用双螺杆挤出机共混制备丙烯腈-丁二烯-苯乙烯塑料(ABS)/聚氯乙烯(PVC)合金。研究了PVC及CPE用量对ABS/PVC合金的拉伸强度、弯曲强度、缺口冲击强度、维卡软化温度、氧指数和熔体流动性的影响。结果表明,随着PVC用量的增加,ABS/PVC合金的拉伸强度略有增加,弯曲强度基本不变,冲击强度呈现先略增加然后显著降低的趋势,维卡软化温度降低,氧指数增加;随着CPE用量增加,ABS/PVC合金的缺口冲击强度增加,拉伸强度和弯曲强度降低,氧指数和维卡软化温度变化很小,当ABS/PVC/CPE为40/60/15时,合金的拉伸强度为39.8 MPa、弯曲强度为60.8 MPa、缺口冲击强度为18.3 kJ/m2,氧指数为29.7%。     

改性伊利石对ABS／EVAC膨胀阻燃复合材料的协效作用

采用十六烷基三甲基溴化铵(OTAB)对伊利石(ILT)进行表面处理,以改善其与聚合物基体之间的相容性,通过对比实验得出有机改性伊利石(OILT)使复合材料具有更优异的综合力学性能。同时研究了OILT用量对丙烯腈–丁二烯–苯乙烯塑料(ABS)／乙烯–乙酸乙烯酯塑料(EVAC)阻燃复合材料力学性能、阻燃性能和热稳定性能的影响,结果表明,当OILT用量为1%时,复合材料的拉伸强度最大,为16.85 MPa,冲击强度达到4.3 kJ／m2,氧指数也达最大值27.3%,燃烧级别达到V–0级,且具有最好的起始热稳定性能。适量的OILT对ABS／EVAC阻燃复合材料具有良好的阻燃协效作用。     

适用于3D打印技术的ABS/SEBS复合材料制备

采用热塑性弹性体苯乙烯–乙烯–丁烯–苯乙烯嵌段共聚物(SEBS)对丙烯腈–丁二烯–苯乙烯塑料(ABS)进行改性,制备3D打印ABS/SEBS复合材料,研究了SEBS的用量对3D打印ABS/SEBS复合材料流动性能、力学性能与热降解行为的影响。结果表明,随SEBS用量的增加,ABS/SEBS复合材料的熔体流动速率先增加后降低;随SEBS用量增加,ABS/SEBS复合材料的冲击强度增加,SEBS能提高ABS/SEBS复合材料的断裂伸长率,但同时也使拉伸强度和弯曲强度降低;随SEBS用量的增加,ABS/SEBS复合材料的热稳定性增加;当SEBS质量分数为15%时,ABS/SEBS复合材料在3D打印中的综合性能最好。     

SBS对3D打印ABS复合材料性能的影响

用苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改性苯乙烯-丁二烯-丙烯腈共聚物(ABS),制备3D打印用ABS改性复合材料,研究了SBS的用量对ABS复合材料性能的影响。采用熔体流动速率仪表征了复合材料的熔体流动速率,万能力学试验机和悬壁梁冲击试验机测试了复合材料的力学性能。研究结果表明,随SBS用量增加,复合材料的熔体流动速率增加,5%SBS的加入能使复合材料的熔体流动速率增加42.1%;随SBS用量增加,复合材料的冲击强度增加,弯曲强度降低;SBS能提高复合材料的断裂伸长率,增加其韧性,但同时也使拉伸强度降低。     

PVC／胶粉热塑性弹性体的制备与性能研究

以聚氯乙烯(PVC)和胶粉为主要原料,采用共混的方法制备了PVC／胶粉热塑性弹性体,研究了胶粉的改性剂、PVC的改性剂和胶粉的用量等对PVC／胶粉热塑性弹性体性能的影响,并与国标GB／T 18173.1–2012所要求的性能进行比对。研究结果表明,使用橡胶再生剂RV改性胶粉所制得的PVC／胶粉热塑性弹性体综合性能最优;使用乙烯–乙酸乙烯酯塑料(EVAC)、苯乙烯–丁二烯–苯乙烯塑料(SBS)改性PVC时,EVAC的改性效果优于SBS,使用15份EVAC所制得的PVC／胶粉热塑性弹性体具有更佳的力学性能、耐老化性能,且满足国标要求;随着胶粉用量的增加,PVC／胶粉热塑性弹性体的综合力学性能下降,耐老化性能提高,使用30份改性胶粉时性价比最高,同时满足国标GB／T 18173.1–2012要求。     

增韧改性剂对ABS/DBDPE/Sb_2O_3共混体系性能的影响

研究了苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)、氯化聚乙烯(CPE)、ABS粉料、甲基丙烯酸甲酯-丁二烯-苯乙烯共聚物(MBS)和聚硅氧烷几种改性剂对ABS/DBDPE/Sb2O3体系的增韧作用。结果表明,SBS、CPE、ABS粉料、MBS和聚硅氧烷对阻燃ABS复合材料有很好的增韧作用,可获得具有良好阻燃性能和物理机械性能的复合材料,其中加入CPE、MBS及聚硅氧烷并不影响复合材料的阻燃性能。     

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。