影响脱醇型RTV-1硅橡胶硫化速度的因素

以α,ω-二羟基聚二甲基硅氧烷(107硅橡胶)、交联剂、催化剂、偶联剂为原料,制得脱醇型单组分室温硫化(RTV-1)硅橡胶。考察了107硅橡胶的黏度、交联剂用量、催化剂种类、偶联剂类型和用量对脱醇型RTV-1硅橡胶硫化速度的影响。结果表明,当107硅橡胶的黏度为60 000 m Pa·s,交联剂用量为4%,1%的钛酸酯配合物1作为催化剂,偶联剂KH-792的用量为0.3%时,制得的脱醇型RTV-1硅橡胶具有较好的硫化速度,表干时间为15 min,8 h硫化深度为1.32 mm,24 h硫化深度为2.24 mm。     

脱醇型单组分室温硫化硅橡胶的研制

以乙烯基三甲氧基硅烷为封端剂,对α,ω-二羟基聚二甲基硅氧烷(107胶)进行封端制得烷氧基封端的107胶,以此为基胶,加入交联剂、填料、自配的钛催化剂,制得了一种贮存稳定性较好的脱醇型单组分室温硫化硅橡胶;并考查了交联剂的用量、填料的用量以及不同型号自配的催化剂对胶的性能以及贮存稳定性的影响。结果表明,100份封端107胶中添加5份交联剂、120份填料、4份催化剂制备的胶贮存期大于12个月,拉伸强度达到2.38MPa,断裂伸长率达到435%。     

单组分脱醇型密封胶的研制

以端羟基聚二甲基硅氧烷(107硅橡胶)为基胶、甲基三甲氧基硅烷和乙烯基三甲氧基硅烷为交联剂、纳米碳酸钙和气相法白炭黑为补强填料、硅烷偶联剂为增粘剂,有机钛为催化剂,制得单组分脱醇型室温硫化(RTV-1)硅橡胶。研究了基胶黏度,填料、交联剂、增粘剂的种类和用量对脱醇型RTV-1硅橡胶性能的影响。较佳配方为:100份黏度50 000 mm2/s的107硅橡胶、5份甲基三甲氧基硅烷与乙烯基三甲氧基硅烷按质量比7∶3复配的交联剂、0.4～0.6份自制氨基硅烷偶联剂。按此配方制得的RTV-1硅橡胶的性能较好。     

烷氧基封端107硅橡胶的制备新工艺

采用烷氧基硅烷对107硅橡胶进行封端改性,研究了烷氧基封端107硅橡胶的封端工艺。探讨了催化剂种类、封端剂种类、催化剂用量、反应温度和反应时间对107硅橡胶封端效果的影响。结果表明,往107硅橡胶中加入0.01~0.1份KOH碱胶,1份乙烯基三甲氧基硅烷,在80℃下反应60 min,再以磷酸酸胶中和体系,可以避免室温硫化硅橡胶出现"黏度上涨"现象,获得最佳的封端效果。     

照明用高强度有机硅密封胶的研究

以烷氧基聚二甲基硅氧烷(封端107硅橡胶)为原料,气相白炭黑和纳米碳酸钙等为补强填料,甲基三甲氧基硅烷及聚甲基三甲氧基硅烷混合物为交联剂,采用双乙酰乙酸乙酯钛酸二异丙酯螯合物催化剂,氨基环氧基硅烷回流物为粘附促进剂,制备高强度有机硅密封胶。研究了封端107胶黏度、补强填料用量、混合交联剂用量、催化剂用量对高强度有机硅密封胶性能的影响。结果表明,采用黏度为1500 mPa·s封端107硅橡胶100份,白炭黑35份,碳酸钙100份,交联剂3份,催化剂2份,粘附促进剂0.8份,制得的密封胶综合性能最佳,具有最大的拉伸强度和剥离强度。     

烷氧基封端聚二甲基硅氧烷的合成及表征

以α,ω-二羟基聚二甲基硅氧烷为基础聚合物、烷氧基硅烷为封端剂,在催化剂存在下进行脱醇缩合反应,制得烷氧基封端聚二甲基硅氧烷。探讨了催化剂用量和封端剂种类对封端效果的影响,采用红外光谱和核磁共振表征产物结构,并考察了产物的贮存稳定性。结果表明,实验成功制得了烷氧基封端聚二甲基硅氧烷,较佳的催化剂用量为0. 09%。当采用乙烯基三甲氧基硅烷作为封端剂时,封端效率为94%,产物经100℃×72 h和常温12个月贮存后,黏度变化率均小于5%,经钛酸酯法测试无明显"黏度高峰"现象,贮存稳定性良好,可作为单组分室温硫化硅橡胶的基础聚合物。     

车灯用脱醇型RTV-1有机硅密封胶的研制

以α,ω-二羟基聚二甲基硅氧烷(107硅橡胶)为基础聚合物,碳酸钙为填料,配以增塑剂、交联剂等制得车灯用脱醇型单组分室温硫化(RTV-1)有机硅密封胶。研究了107硅橡胶黏度、填料粒径和用量、交联剂用量、增粘剂种类和用量对密封胶性能的影响。结果表明,采用50份黏度60 000 m Pa·s的107硅橡胶,50份平均粒径80 nm的碳酸钙配成基胶,增塑剂用量(占基胶质量)5%,甲基三甲氧基硅烷3%,钛酸酯配合物1%,脲基增粘剂复合物用量0.3%条件下制备的密封胶性能较优,表干时间12 min,挤出速率165 m L/min,深层硫化速度2.3 mm/(24 h),拉伸强度2.26 MPa,拉断伸长率388%,剪切强度1.74 MPa,对聚碳酸酯和经等离子处理的聚丙烯粘接良好,适用于车灯的粘接密封。     

钛酸酯催化双组分室温硫化硅橡胶的研制

以α,ω-二羟基聚二甲基硅氧烷为原料,甲基三甲氧基硅烷为封端剂制得烷氧基封端107硅橡胶,并以其为基胶,钛酸酯配合物为催化剂,纳米活性碳酸钙为填料,3-氨丙基三乙氧基硅烷为偶联剂,甲基三甲氧基硅烷、正硅酸乙酯为交联剂,制备了双组分脱醇缩合型室温硫化液体硅橡胶。研究了A组分粉液比、钛酸酯配合物用量对硅橡胶性能的影响。结果表明,随着A组分粉液比从0.80逐渐上升到1.10,硅橡胶的挤出性从113 g/min降至65 g/min,表干时间从24 min缩短至15 min,拉伸强度从1.48MPa上升至1.71 MPa,拉断伸长率从482%降至224%,邵尔A硬度从31度升至45度;随着钛酸酯配合物相对自制封端107硅橡胶的质量分数从0.5%增加到5%,硅橡胶的拉断时间由68 min缩短至8 min,硫化胶的剪切强度由1.03 MPa提高到1.75 MPa。     

单组分脱醇型透明有机硅密封胶的制备与性能研究

采用α,ω-二羟基聚二甲基硅氧烷经乙烯基三甲氧基硅烷封端制得烷氧基封端107硅橡胶,在烷氧基封端107硅橡胶中投入功能助剂和填料,制备一款综合性能较佳、储存稳定的单组分脱醇型透明有机硅密封胶;试验逐一分析了交联剂、催化剂以及催化剂、偶联剂种类对密封胶粘接、硫化性能和储存稳定性的影响。试验结果发现,选用烷氧基封端107基胶100份、交联剂4份、白炭黑填料9份、硅氮烷0.6份、自制偶联剂1.2份、催化剂锡混合物0.3份,以此配方所研制脱醇型有机硅密封胶储存长达9个月,拉伸强度为1.35MPa,拉断伸长率为173%,9min就可以表干,弹性硬度适中。     

超细活性碳酸钙补强脱酮肟型RTV-1硅橡胶的制备及性能

以超细活性碳酸钙为补强剂制备脱酮肟型单组分室温硫化(RTV-1)硅橡胶,并研究了107胶黏度、碳酸钙用量、交联剂和偶联剂种类及用量等对RTV-1硅橡胶性能的影响。结果表明,采用黏度为50 000 mPa.s的107胶、80份超细活性碳酸钙、10份甲基三丁酮肟基硅烷、2份乙烯基三丁酮肟基硅烷及2份硅烷偶联剂KH560,可制备出综合性能较好的脱酮肟型RTV-1硅橡胶,拉伸强度达2.29 MPa,断裂伸长率达500%。     

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.