高性能双组分室温固化环氧胶的研制

以环氧E-51、增韧剂R-1000、偶联剂KH-560、聚酰胺651、酚醛胺和促进剂DMP-30为原料,制备了一种高粘接性能、双组分室温固化环氧胶。研究了DMP-30的用量对环氧胶适用期的影响;R-1000、KH-560的用量和A、B组分配比对环氧胶粘接性能的影响。结果表明,m₍聚酰胺+酚醛胺/m_DMP-30=100/12时,环氧胶的适用期为40～45min;m_E-51/m_R-1000=100/16、m_E-51/m_KH-560=100/2,m_A/m_B=3.0/1.0时,环氧胶的粘接性能最佳。     

适用于低温固化环境的环氧树脂体系的选择

环氧固化体系的干燥时间与固化促进剂用量以及固化的环境温度密切相关。随着固化促进剂用量的增加,体系的干燥性能逐步得到提升。本文解析了固化促进剂DMP-30的作用机理并用红外谱图法表征了微观反应过程,并且通过对DMP-30在-15℃到5℃的低温固化条件下对环氧固化体系干燥性能的影响,以及不同的DMP-30加入量对体系机械性能影响的研究,结合考察环氧活性稀释剂对降低环氧固化体系粘度的作用,最终得出了环氧体系中较为合适的环氧促进剂加入量和环氧稀释剂的种类。     

室温固化环氧胶粘剂的研制和改性

以环氧E-51、聚酰胺651、促进剂DMP-30、溶剂苯甲醇、偶联剂KH-560为原料,制备了一种室温固化的高粘接性胶粘剂。研究了DMP-30和苯甲醇用量对胶粘剂粘接性能的影响,并用氧化石墨烯对环氧胶粘剂进行增韧改性。结果表明,DMP-30和苯甲醇的用量分别为15%和20%时,胶粘剂的剪切强度最高。另外,氧化石墨烯对环氧胶粘剂有明显的增韧效果,用量为0.6%时,胶粘剂的剪切强度最高,达到25.81 MPa,比未添加时提高了34.3%。     

室温快固环氧密封胶的增韧改性研究

以DER331、DER791为基体,692为稀释剂,纳米二氧化硅、纳米碳酸钙、重钙为填料,聚硫醇与聚醚胺为复配固化剂,研究了促进剂DMP-30添加量对凝胶时间及剪切强度的影响,CYH-277、聚氨酯改性环氧树脂添加量对环氧密封胶抗冲击性能的影响,AB组分配比对环氧密封胶剪切强度的影响。结果表明:DMP-30可提高环氧密封胶的固化速度,CYH-277对聚硫醇/聚醚胺体系的抗冲击性能影响不明显,聚氨酯改性环氧可提高聚硫醇/聚醚胺体系的抗冲击性能,A/B组分配比值在0.9~1.1时,固化时间和凝胶时间最小,环氧密封胶的剪切强度也最大,环氧胶可在30 min固化。     

环氧粘合剂粘接聚四氟乙烯板/不锈钢的耐温性研究

考察了经表面化学活化的3种纯聚四氟乙烯(PTFE)板和1种聚苯酯填充PTFE板在室温和高温下的拉伸性能,用两类环氧粘合剂DG–3S和JF205–1对这4种PTFE板与不锈钢进行了粘接,研究了室温和高温下这两种粘合剂的粘接效果。结果表明,4种活化PTFE板经高温老化后的拉伸性能变化不明显;室温下两种环氧粘合剂对4种PTFE板与不锈钢的粘接性能均良好,但DG–3S粘合剂不适合高温下对PTFE板/不锈钢的粘接,经耐热改性的JF205–1粘合剂在300℃下的粘接性能则较好;JF205–1粘接聚苯酯填充PTFE板/不锈钢的实际粘接性能较好且具有高的耐磨性能和抗蠕变性,在满足实际粘接要求的情况下可应用于制造发动机零部件。     

固化促进剂对环氧树脂固化物性能的影响

借助透光率/雾度仪、DSC和SEM比较了四乙基溴化铵(TEABr)、二甲基苄胺(DBMA)、2-乙基-4-甲基咪唑(2,4-EMI)、2,4,6-三(二甲基胺基甲基)苯酚(DMP-30)以及有机膦/溴络合物(AO-4)对E-51环氧树脂/酸酐固化体系性能的影响。结果表明,固化促进剂的加入可不同程度地提高环氧树脂的固化速率,改善固化物的透明度和耐热稳定性。AO-4质量分数为0.5%～1.0%,120℃下反应得到的环氧/酸酐固化物无色透明,综合性能最佳。     

DMP-30作用下丙酮对环氧树脂与E玻纤结合的影响

采用丙酮稀释含有促进剂DMP-30的环氧树脂(E-51)胶液,并以此胶液对E玻璃纤维进行包覆。通过示差扫描量热法、凝胶化实验和傅里叶变换红外光谱研究了DMP-30作用下环氧树脂的固化特性;通过弯曲强度实验和扫描电子显微镜分析探讨了丙酮对该树脂胶液包覆玻纤的增强效果。结果表明:环氧树脂E-51/固化剂甲基六氢苯酐/促进剂DMP-30质量比为100/72.9/1.5,固化工艺为102℃/0.5 h+124℃/1 h+141℃/1 h,丙酮质量分数为5%(以环氧树脂为基准)时,体系的弯曲强度比无丙酮稀释时提高了24.7%。这是由于丙酮降低了树脂胶液粘度,改善了树脂胶液与玻纤的界面结合,形成均匀的结合状态。     

非等温DSC法研究环氧树脂/聚硫醇体系固化动力学

采用实时红外光谱(Real-Time FTIR)和非等温DSC法研究了促进剂2,4,6-三(二甲胺基甲基)苯酚(DMP-30),N,N-二甲基苄胺(BDMA)和三乙胺(TEA)对环氧树脂/聚硫醇体系固化的影响。利用n级模型和Malek法对体系DSC曲线进行分析,计算树脂体系的反应动力学参数。结果表明,DMP-30的催化效率高于BDMA和TEA。25℃下质量分数5%的DMP-30对环氧树脂/聚硫醇体系的促进作用最明显,20 min内环氧基的转化率达到85.2%。加入促进剂后的环氧树脂/聚硫醇体系可用双参数自催化模型来拟合,反应级数m,n分别为0.297和1.276,活化能为37.344 k J/mol。     

促进剂对低温固化剂-环氧树脂体系性能的影响

分别选用二乙烯三胺和间二甲苯二胺与甲醛、腰果酚按照不同比例反应制得13种改性胺环氧低温固化剂,通过剪切强度,反应活化能和固化度测定以及红外光谱分析研究了不同促进剂DMP-30用量对环氧树脂及上述胺体系的物理性能、固化过程及固化产物性能的影响。结果表明:DMP-30与环氧树脂/胺体系具有一定的匹配性,促进剂具有正负效应。对于环氧和改性胺反应配比n(腰果酚)∶n(间二甲苯二胺)∶n(醛)=1.0∶1.0∶1.0的体系而言,促进剂的最佳添加质量分数为2%。     

缠绕复合式气瓶的环氧树脂胶粘剂

研究一种煤矿安全生产中用于复合式氧气瓶的低温固化环氧树脂胶粘剂,在以多亚乙基多胺为固化剂主料的基础上,调整硫脲、2-甲基咪唑、DMP-30用量,确定其最佳质量比为1 00∶0 20∶0 03∶0 20,选择适宜的反应温度和时间,合成出完全符合实际需要的固化剂。使用该固化剂与环氧树脂及溶剂混配制胶,其固化时间小于7h,固化温度低于70℃,凝胶时间大于3h。该胶应用于气瓶缠绕粘接各项性能指标均能达到要求。     

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.     

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.     

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。     

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.     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Some Large Wood-Boring Beetles in Southeastern USA

Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.