炭黑品种对ACM/ECO并用胶性能的影响

研究炭黑品种对ACM/氯醚橡胶(ECO)并用胶硫化特性、物理性能、耐热老化性能、耐油性能和动态力学性能的影响.结果表明;炭黑品种对ACM/ECO并用胶的焦烧时间和正硫化时间影响不大;随着炭黑粒径的增大、结构度降低,ACM/ECO并用胶的拉伸强度、拉断伸长率、撕裂强度、压缩永久变形和耐油性能均有不同程度的下降;炭黑粒径对ACM/ECO并用胶的耐热老化性能和玻璃化温度影响不大,炭黑粒径大的并用胶tanδ值较大.     

稻壳源白炭黑/炭黑/天然橡胶复合材料的性能研究

试验研究稻壳源白炭黑/炭黑并用对天然橡胶硫化胶性能的影响。结果表明:当稻壳源白炭黑/炭黑用量比较高时,胶料的M_L较大,t_(10)较短,t_(90)较长,物理性能较差;当稻壳源白炭黑、炭黑用量较为均衡时,硫化胶的物理性能变化不大,动态力学性能较好;稻壳源白炭黑/炭黑用量比对硫化胶耐寒性能的影响不大;当稻壳源白炭黑/炭黑用量比为20/40和25/35时,硫化胶的综合性能较好。     

氢化丁腈橡胶/丁腈橡胶耐热密封复合材料的性能研究

研究炭黑、白炭黑、碳酸钙和陶土对氢化丁腈橡胶（HNBR）/丁腈橡胶（NBR）耐热密封复合材料的硫化特性、物理性能、耐热空气老化性能和耐油性能的影响。结果表明：白炭黑补强并用胶的耐热空气老化性能和耐油性能较好,但压缩永久变形大;陶土和碳酸钙补强并用胶的各项性能均较差;炭黑N220补强并用胶的物理性能较好,压缩永久变形小,更适合作为制备HNBR/NBR耐热密封材料的补强填料;炭黑N220和N330在并用胶中分散均匀,而炭黑N770分散不均匀,粒子聚集体较多。     

补强体系对NBR油封性能的影响

研究补强体系对NBR油封胶料性能的影响,通过台架试验评价油封的使用性能.结果表明,采用高耐磨炭黑/半补强炭黑或快压出炭黑补强的NBR硫化胶物理性能优异,但不适宜生产中高速油封;采用白炭黑/轻质氧化镁补强的NBR硫化胶物理性能略差,但可满足油封的要求,且耐热老化和耐油性能良好,所制备油封使用性能优异.     

补强剂对AEM/PAM15 TPV性能的影响

采用不同粒径的炭黑和白炭黑补强体系,填充不同硫化体系的AEM/PAM15TPV,研究了不同补强剂对不同硫化体系AEM/PAM15TPV的补强效果。结果表明,炭黑和白炭黑对于不同硫化体系AEM/PAM15TPV有一定的补强效果,其中对胺类硫化体系补强效果最好。经过补强,体系的拉伸强度和定伸应力提高,但补强剂用量过多时,体系的性能降低;加入炭黑和白炭黑增强了界面的相互作用,限制了分子链的运动,降低了拉断伸长率。     

ACM/EPDM并用胶的制备及性能

以丙烯酸酯橡胶(ACM)和三元乙丙橡胶(EPDM)为主要原料制备共混材料。通过ACM/EPDM的质量比、白炭黑用量和硫化工艺条件的研究发现,用白炭黑作补强剂的硫化胶性能优于用炭黑作补强剂的硫化胶;当EPDM/ACM为25/75,硫化条件为160℃×10 MPa×30 min时,该共混材料具有良好的力学性能、耐磨、耐热和耐油性,ACM/EPDM并用胶的性能优于ACM或EPDM的性能。     

NBR/PA12 TPV的制备与性能研究

采用动态硫化方法制备NBR/聚十二内酰胺(PA12)热塑性硫化胶(TPV),研究硫化体系、NBR丙烯腈含量和NBR/PA12并用比对NBR/PA12 TPV性能的影响。结果表明,采用马来酰亚胺衍生物类硫化剂A/促进剂DM硫化体系,NBR/PA12 TPV呈两相海-岛结构,体系中PA12的结晶度较大,综合物理性能较好;NBR丙烯腈含量越大、在NBR与PA12总量不变的前提下,PA12用量越大,NBR/PA12 TPV综合物理性能和耐油性能越好。     

白炭黑对再生顺丁橡胶／聚烯烃弹性体热塑性硫化胶性能的影响

采用动态硫化技术制备再生顺丁橡胶(RBR)/聚烯烃弹性体(POE)共混型热塑性硫化胶(TPV),研究硫黄硫化体系RBR/POE TPV的硫化特性、白炭黑对TPV物理性能和动态力学性能的影响。结果表明:RBR/POE TPV在硫黄硫化体系下能够继续硫化;随着白炭黑用量的增大,RBR/POE TPV的300%定伸应力和拉伸强度增大,拉断伸长率和拉断永久变形减小;偶联剂Si69改性白炭黑补强RBR/POE TPV的300%定伸应力、拉伸强度和储能模量与未改性白炭黑补强体系相比明显增大,拉断伸长率和拉断永久变形有所降低。     

水油环境用丁腈橡胶/氯丁橡胶共混胶性能研究

对丁腈橡胶(NBR)/氯丁橡胶(CR)并用胶在水、油环境下性能的影响因素进行研究,主要研究NBR/CR配比、硫化体系、炭黑和白炭黑对并用胶的物理性能、体积电阻率和耐水、耐油性能的影响。同时研究了硫化时间对NBR/CR并用胶性能的影响。结果表明:NBR/CR并用胶(并用比为70/30)最佳硫化体系为:氧化锌5,氧化镁6,促进剂DM0.4,硫黄2;随着CR用量的增大,NBR/CR并用胶拉伸强度和体积电阻率先增大后减小,耐油性能增强;炭黑N550填充的并用胶的综合性能最佳,且当炭黑N550用量为50份、白炭黑用量为20份时,并用胶性能最佳;最佳硫化时间为50 min。     

白炭黑/炭黑混合填料对氟橡胶/硅橡胶共混胶性能的影响

采用沉淀白炭黑和高耐磨炭黑作为氟橡胶/硅橡胶共混胶的填料.研究以不同质量比混合的沉淀白炭黑和高耐磨炭黑对氟橡胶/硅橡胶共混胶的硫化特性、门尼粘度、力学性能、耐热老化性能和耐油性能的影响,并通过RPA分析表征填料-填料的相互作用,采用SEM表征白炭黑/炭黑混合填料在氟橡胶/硅橡胶共混胶中的分散性.结果表明,随着混合填料中白炭黑所占比例的增大,氟橡胶/硅橡胶共混胶的硫化转矩升高,焦烧时间(t10)缩短,正硫化时间(t90)延长,门尼粘度增大.氟橡胶/硅橡胶共混胶的力学性能,耐热老化性能和耐油性能都随着混合填料中白炭黑用量增多而提高.RPA分析表明,全部采用白炭黑补强的共混胶Payne效应最明显,炭黑补强的共混胶Payne效应最弱.SEM分析表明,白炭黑在共混胶中分布比炭黑更加均匀,填料聚集体粒径较小.     

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。