核桃壳粉/丁苯橡胶复合材料的制备与性能研究

采用核桃壳粉(WSP)和丁苯橡胶(SBR)制备WSP/SBR复合材料,研究WSP和偶联剂Si69对复合材料硫化特性、物理性能和动态性能的影响。结果表明,添加未改性的WSP,混炼胶的F_(max)-F_L总体减小,复合材料的物理性能降低,抗湿滑性能提高;经偶联剂Si69改性后,混炼胶的硫化时间延长,交联密度增大,复合材料的拉伸强度提高,耐磨性能改善,压缩疲劳温升降低,胶料的抗湿滑性能提高,滚动阻力降低。     

白炭黑/溶聚丁苯橡胶复合材料的填料网络结构与动态黏弹性能

用橡胶加工分析仪研究了白炭黑用量和偶联剂Si 69原位改性对白炭黑/溶聚丁苯橡胶复合材料中填料网络结构与动态黏弹性能的影响.结果表明,白炭黑用量为30份(质量,下同)时网络结构尚未形成,不能测定结合胶;填充了50份和 70份的白炭黑复合材料的结合胶含量较低,其网络结构的结点类型以刚性结点为主,混炼胶和硫化胶的Payne效应明显.混炼胶的温度扫描结果表明,随白炭黑用量增加,复合材料中填料的聚集程度加剧.经Si 69原位改性后,复合材料的结合胶含量大大提高,网络结构的结点类型以柔性结点为主,混炼胶和硫化胶的Payne效应明显减弱.在10.04%的大应变下进行频率扫描时,经Si 69原位改性硫化胶的储能模量和损耗因子随频率的增大而增大,且明显低于未改性者.     

烷偶联剂原位改性白炭黑/溶聚丁苯橡胶 复合材料的流变性能和力学性能研究

制备3种硅烷偶联剂（Si69,Si75,NXT）原位改性白炭黑/溶聚丁苯橡胶（SSBR）复合材料,研究硅烷偶联剂对白炭黑/SSBR复合材料流变性能和力学性能的影响。结果表明：硅烷偶联剂NXT在降低善白炭黑填料网络化程度方面比偶联剂Si69和Si75的效果更明显;硅烷偶联剂NXT改性白炭黑/SSBR复合材料（混炼胶和硫化胶）的剪切储能模量较低,Payne效应较弱,加工性能较好,损耗因子和活化能较小,拉伸储能模量对温度依赖性较弱,硬度、拉伸强度和拉断伸长率相当,撕裂强度较大,白炭黑分散性优异,白炭黑与橡胶之间的相互作用较强。     

偶联剂Si69改性白炭黑对NR/SSBR并用胶性能的影响

试验研究偶联剂Si69用量和白炭黑改性方法对白炭黑填充NR/SSBR并用胶性能的影响.结果表明,当采用直接加入法改性白炭黑时,随着偶联剂Si69用量的增大,Payne效应减弱,NR/SSBR并用胶的t10延长,t90缩短,硫化胶的物理性能提高,偶联剂Si69用量以4 5份为宜.与直接加入法改性白炭黑填充并用胶相比,预处理法改性白炭黑填充并用胶的Payne效应减弱,拉伸强度和撕裂强度增大;高温静置处理法改性白炭黑填充并用胶的定伸应力、拉伸强度和损耗模量增大.     

硅烷偶联剂对白炭黑Z1165MP填充SSBR/BR性能的影响

研究了硅烷偶联剂NXT、Si747改性白炭黑Z1165MP填充SSBR/BR的硫化特性、物理性能及动态性能,并与Si69进行了对比。结果表明,与偶联剂Si69和Si747相比,NXT具有较好的抗焦烧性能,当偶联剂用量较高时,这种优势更加明显,3种偶联剂的抗焦烧能力顺序为NXTSi69Si747。Si69和Si747改性体系,当偶联剂用量分别达到3.2份和6.4份后,硫化胶的拉伸强度明显下降,拉断伸长率逐渐降低;NXT改性体系,拉伸强度在实验用量范围内变化不大,拉断伸长率明显降低,当用量达到1.6份后,降低程度明显减小。3种改性体系的撕裂强度均有所改善,压缩疲劳温升和阿克隆磨耗体积明显降低。混炼胶和硫化胶的G′0.56%和G′0.56%-G′100%均随着偶联剂用量的增加明显降低,当偶联剂用量达到4.8份后NXT和Si747改性体系的Payne效应较Si69改性体系小。     

改性淀粉对炭黑填充丁苯橡胶/顺丁橡胶并用胶性能的影响

用改性淀粉替代部分炭黑填充丁苯橡胶(SBR)/顺丁橡胶(BR)并用胶,考察了改性淀粉用量及偶联剂种类对混炼胶硫化特性及硫化胶物理机械性能和动态力学性能的影响.结果表明,用改性淀粉替代部分炭黑可对SBR/BR混炼胶的硫化产生明显的延迟作用,但改性淀粉用量的变化对焦烧时间与正硫化时间影响不大;添加偶联剂KH-570或NDZ-201延迟了混炼胶的硫化过程,KH-550能大幅度地促进硫化作用,Si-69对于体系的硫化性能略有影响;随着改性淀粉用量的增加,SBR/BR硫化胶的拉伸性能、耐磨耗性均有所降低,但弹性、动态生热和滞后性能得到了明显改善,改性淀粉最佳用量为5～8份;各种偶联剂均可提高SBR/BR硫化胶的拉伸性能,硅烷偶联剂Si-69和KH-570对弹性和动态生热也略有改善,添加偶联剂KH-550改善了SBR/BR硫化胶的抗湿滑性能,但滞后性能变差,添加偶联剂KH-570或Si-69对SBR/BR硫化胶动态力学性能的影响较小,综合考虑,以添加偶联剂KH-570较好.     

多相炭黑G10填充半钢轮胎胎面胶性能研究

研究偶联剂Si69用量对多相炭黑G10填充半钢轮胎胎面胶性能的影响，并与炭黑及炭黑/白炭黑并用填充胎面胶性能进行对比。结果表明：与炭黑填充胶料相比，炭黑/白炭黑并用填充胶料的门尼粘度较大，t90延长，t10缩短；与炭黑/白炭黑并用填充胶料相比，多相炭黑G10填充胶料的门尼粘度明显减小，t90缩短，混炼胶的Payne效应明显减弱，硫化胶的拉伸强度增大，阿克隆磨耗量和DIN磨耗量减小，压缩生热明显降低，混炼胶中炭黑分散性明显改善；随着多相炭黑G10填充胶料中偶联剂Si69用量的增大，胶料硫化特性和物理性能变化不大，损耗因子减小，其中偶联剂Si69用量为白炭黑用量8%的胶料生热较低，多相炭黑G10分散效果较好。     

湿法改性高岭土与不同填料在SBR中的应用

将湿法改性高岭土与未改性高岭土、炭黑、白炭黑以及碳酸钙分别填充到SBR中制备复合材料,并对其性能进行了研究。结果表明,炭黑填充SBR复合材料的综合性能最好,改性高岭土次之,白炭黑填充略好于高岭土填充,碳酸钙填充的性能最差;与未改性高岭土相比,改性高岭土胶料的加工性能得到改善,拉伸强度、定伸应力、撕裂强度均增大,耐磨性及耐老化性能变好。     

类绢云母/SBR复合材料性能及其改性研究

研究类绢云母/丁苯橡胶(SBR)复合材料的硫化特性及物理性能。结果表明:添加类绢云母后的SBR胶料物理性能提高;类绢云母对SBR的补强效果优于碳酸钙、高岭土和沉淀硫酸钡等通用无机填料;偶联剂改性有利于提高类绢云母/SBR复合材料的性能,偶联剂Si69的改性效果较突出;当偶联剂Si69用量为类绢云母用量的10%时,胶料的拉伸强度和耐磨性能较好。     

用硫化仪数学分析法确定白炭黑在丁苯橡胶中最佳填充量

以谷氨酸二硫代氨基甲酸镧(La-GDTC)改性白炭黑(Si O2)填充丁苯橡胶(SBR),采用硫化仪数学分析法确定了Si O2最佳用量,通过橡胶加工分析仪分析了填料网络结构的形成,研究了SBR/La-GDTC/Si O2复合材料的拉伸性能。结果表明,采用硫化仪数学分析法确定Si O2最佳用量为40份;当Si O2用量不超过40份时,SBR/La-GDTC/Si O2复合材料的Payne效应不明显,当Si O2用量为50份时,复合材料出现了明显的Payne效应;随着Si O2用量的增加,SBR/La-GDTC/Si O2复合材料的拉伸强度先升高后下降,当Si O2用量为40份时达到最大值(28.03 MPa),表明采用硫化仪数学分析法可以快捷、准确确定在橡胶复合材料中无机填料的最佳用量。     

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。