环氧树脂增韧固化剂的合成与性能研究

以聚硫橡胶、乙二胺为原料合成了新的环氧树脂固化剂(简称DAJL),通过力学性能测试研究了其用量对环氧固化产物性能的影响。结果表明,随着DAJL用量的增加,环氧树脂固化物的拉伸强度、弯曲强度均有所下降,冲击强度先增大后减小,当DAJL的质量分数为20%时,冲击强度达到最大(3.50 k J/m2),韧性较好,同时其他力学强度较高。冲击端口的SEM照片表明,DAJL固化剂的加入可以引发银纹,吸收冲击能,终止裂纹扩散。     

耐原子氧刻蚀有机硅改性环氧树脂的开发

通过端环氧苯基硅氧烷与双酚A型环氧树脂的共聚反应制得有机硅改性环氧树脂。研究了苯基硅氧烷用量对有机硅改性环氧树脂性能的影响。结果表明,有机硅改性环氧树脂固化物的冲击强度和耐原子氧剥蚀性能有明显提高;当改性剂苯基硅氧烷质量分数为30%时,有机硅改性环氧树脂的冲击强度由6.7k J/m~2提高到33.4 k J/m~2,原子氧辐照后质量损失降低为纯环氧树脂的20%。     

含硅聚氨酯改性水性环氧固化剂的制备与性能

以聚醚二元醇(N210)、异佛尔酮二异氰酸酯(IPDI)、羟基硅油为原料,合成了异氰酸酯基封端的含硅聚氨酯预聚体(PU-Si),再以PU-Si、环氧树脂E-51、丁基缩水甘油醚单封端的四乙烯五胺(TEPA-660a)为主要原料,制备了含硅聚氨酯改性水性环氧树脂固化剂,将制得的环氧树脂固化剂与环氧树脂E-51混和制得固化膜。用FTIR、TEM、SEM、TG和水接触角测试仪对聚合物的结构与性能进行了表征与测试,并考察了PU-Si含量对固化剂乳化性能、固化膜力学性能、热性能、断面形貌及吸水率的影响。结果表明:当固化膜中PU-Si的质量分数达到18%时,固化膜的综合性能最佳,此时冲击强度为22.45 k J/m~2,拉伸强度为44.7 MPa,热失重5%和50%时的温度分别为205.0和373.8℃,水接触角为96.8°,吸水率仅1.35%,与纯环氧树脂固化膜相比,其柔韧性、耐热性、耐水性等性能均有显著提高。     

聚氨酯改性非离子型水性环氧固化剂的制备与性能

以异佛尔酮二异氰酸酯(IPDI)、环氧树脂(E-44)和聚乙二醇6 000(PEG 6 000)为原料,制备了聚氨酯(PU)型反应性大分子环氧乳化剂,将这种乳化剂与E-44混合均匀后再与正丁基缩水甘油醚单封端的四乙烯五胺(TEPA-660a)反应制备出非离子型水性环氧树脂固化剂。采用红外光谱(FT-IR)、扫描电镜(SEM)、热失重(TG)和粒径测试等方法表征和测试了聚合物的结构、性能及乳液粒径,并研究了乳化剂含量对固化膜断面形貌、力学性能和热性能的影响。结果表明,当乳化剂用量占乳化剂和E-44质量分数的15%时,所制备的非离子水性环2氧树脂固化剂稳定性良好,粒径为216.5 nm,环氧固化膜冲击强度为16.32 k J/m,拉伸强度为33.7 MPa,5%和50%的质量热损失温度分别为175℃和365℃,与未改性环氧固化膜相比,韧性得到明显提高。     

PVC/环氧树脂E51共混物性能的研究

以504及554/504分别作为固化剂,采用锥形双螺杆挤出机实现了PVC与环氧树脂的熔融共混,制备了PVC/环氧树脂E51共混物。固化剂用量为环氧树脂E51用量的80%时,研究了环氧树脂E51用量、固化剂组成及固化时间对PVC/环氧树脂E51共混物力学性能及维卡软化温度的影响。结果表明:以504及554/504为固化剂,少量环氧树脂E51(4份以内)加入PVC后,有助于提高共混物的拉伸强度、弯曲强度;当环氧树脂E51为2份、固化时间为8h时,共混物维卡软化温度达到最大值100.2℃,比纯PVC高出16.5℃。     

纳米粒子改性环氧树脂玻璃化转变温度的研究

采用示差扫描量热分析(DSC)研究了纳米A l2O3粒子改性的环氧树脂基体玻璃化转变温度与纳米粒子含量之间的关系以及纳米粒子含量对改性体系固化剂用量的影响。结果表明,随着纳米粒子含量的提高,改性树脂的玻璃化转变温度逐渐下降,由纯树脂的224℃下降到182.5℃(纳米粒子用量30%,固化剂添加量70%)。并且纳米粒子的加入会影响树脂基体的固化反应。达到玻璃化转变温度峰值时的固化剂用量并非按照改性体系中环氧树脂含量等当量比加入,而是与纳米粒子含量有关,纳米粒子含量越高,达到玻璃化转变温度峰值时固化剂用量越少。     

PVC/环氧树脂F51共混物性能的研究(一)

采用锥形双螺杆挤出机制备了PVC/环氧树脂F51复合材料,并固定固化剂504用量为环氧树脂F51用量的80%,研究了环氧树脂F51的用量、固化时间及固化剂体系对PVC/环氧树脂F51共混物的聚集态结构、力学性能及耐热性能的影响。研究表明:①当环氧树脂F51用量较少时(如2份),其以小颗粒均匀地分散在基体PVC中,但随着环氧树脂F51用量的增加,其在基体PVC中分散的颗粒越来越大,出现团聚现象;②当环氧树脂F51的用量为2份,固化时间为8h时,共混物的拉伸强度为69.9MPa;当环氧树脂F51的用量为4份,固化时间为8h时,共混物的弯曲强度为92.0MPa;③当环氧树脂F51的用量在6份,固化时间为8h时,共混物的维卡软化温度达到最大值,为102.1℃,比纯PVC增加了23.8℃。     

不同固化剂对于环氧树脂固化物的绝缘性能的影响研究

不同类型的固化剂所制备的环氧树脂固化物，其理化性能具有显著的差异。为了深入研究不同固化剂分子结构对环氧树脂固化物的电气性能的影响，利用3种常用的酸酐固化剂甲基四氢苯酐(MTHPA)、甲基六氢苯酐(MHHPA)、甲基纳迪克酸酐(MNA)与DER331双酚A环氧树脂反应制备了3种环氧树脂固化物，测试了这3种环氧树脂固化物的体积电阻率和击穿电压。结果表明：当固化剂为MTHPA时，环氧树脂固化物击穿电压最高，为40.4 kV·mm^-1，体积电阻率为4.29×10¹⁶Ω·cm，击穿电压较MNA提高了22.4%，体积电阻率提高了73.0%。基于有限元仿真分析了这3种不同结构环氧树脂固化物分子的最高占据轨道(HOMO)和最低未占据轨道(LUMO)的能级差，研究发现，当采用MTHPA作为固化剂的时候，LUMO-HOMO之差达到最大，为5.56 eV，仿真结果表明环氧树脂固化物能级差大小为MTHPA>MHHPA>MNA，该结果和实验结果一致。     

柔性环氧固化剂破解脆性难题

沈阳市东南化工研究所自主研发成功一种T-99柔性环氧树脂固化剂,其突出特点是几乎无味、黏度很低、水白透明、难以挥发、无毒环保。与E-51或128环氧树脂100质量份配合T-99固化剂50质量份,混合后可室温固化,固化物晶莹剔透,彰显柔性、韧性、弹性特征。与其他固化剂迥然不同,具有明显的创新超群性,破解了一直令人困惑的胺类固化剂固化环氧树脂的脆性难题。     

端环氧苯基三(二甲基硅氧烷基)硅氧烷改性环氧树脂的性能研究

采用端环氧苯基三(二甲基硅氧烷基)硅氧烷对环氧树脂进行改性,制备了一系列有机硅改性环氧树脂,研究了端环氧苯基三(二甲基硅氧烷基)硅氧烷对环氧树脂力学性能、热学性能及原子氧剥蚀性能的影响。结果表明,改性树脂的综合性能随着端环氧苯基三(二甲基硅氧烷基)硅氧烷含量的增加而增强。当有机硅质量分数为30%时,有机硅改性环氧树脂的拉伸强度、弯曲强度和冲击强度与纯环氧树脂相比分别由48.2 MPa、100 MPa、12.7 k J/m~2提高至57.2 MPa、126 MPa、18.5 k J/m~2;质量损失率10%时的热失重温度提高了64℃;经过36 h的原子氧辐照后,质量损失率仅为纯环氧树脂的6.4%。     

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.