环氧树脂复合泡沫材料的制备研究

以缩水甘油酯环氧树脂(EP)、酸酐固化剂和空心玻璃微珠为主要原料,通过添加一定的活性稀释剂,高温固化制备了EP复合泡沫材料。研究了空心玻璃微珠的表面改性对复合泡沫材料性能的影响。结果表明,复合泡沫材料性能与空心玻璃微珠的表面性能密切相关,当EP/固化剂/稀释剂的质量比为100/120/15、KH-560改性的空心玻璃微珠用量为30份时,所制备的复合泡沫材料密度为0.826 g/cm3,压缩强度达115.8 MPa,比强度为140.2。     

环氧树脂/空心玻璃微珠复合浮力材料制备及性能

采用硅烷偶联剂KH–550改性空心玻璃微珠(S38HS),并通过旋转脱泡–浇注–模压成型法制备了环氧树脂/空心玻璃微珠复合浮力材料。研究了空心玻璃微珠表面处理、体积分数对复合浮力材料压缩强度和密度的影响。结果表明,表面处理有利于改善环氧树脂和空心玻璃微珠之间的界面,从而提高复合浮力材料的压缩强度。添加高体积分数的空心玻璃微珠有利于降低复合浮力材料的密度,而材料的压缩强度随着空心玻璃微珠体积分数的增加而降低,应该综合考虑空心玻璃微微珠的含量,以获取所需的密度和压缩强度。当空心玻璃微珠体积分数为60%时,复合浮力材料的压缩强度和密度分别为61.41 MPa和0.66 g/cm³。     

一种新型三相复合环氧基泡沫材料的制备

采用滚球法制备了玻璃纤维增强环氧树脂空心球(GFR-EHS),并将GFR-EHS与空心玻璃微珠(HGMS)加入到环氧树脂(EP)中制备了EP/GFR-EHS/HGMS三相复合泡沫材料。利用万能试验机、扫描电子显微镜、电子数码扫描仪等对复合泡沫材料的密度、压缩强度、宏观及微观形貌进行了表征。结果表明:HGMS及GFREHS在EP中分散均匀,界面结合紧密,所制得复合泡沫材料的密度为0.51 g/cm3,压缩强度为27.3 MPa,制备的复合泡沫材料可用作深海浮力材料。     

空心玻璃微珠/环氧树脂基复合泡沫材料研究进展

综述了环氧树脂基复合泡沫材料中空心玻璃微珠的改性方法,以及近几年来环氧树脂基复合泡沫材料在强度、密度、吸水率等方面的研究进展。并展望了环氧树脂基复合泡沫材料的未来发展方向。     

高性能复合泡沫材料的制备与性能研究

以环氧树脂、氰酸酯树脂和中空玻璃微珠为原料制备了高性能复合泡沫材料,通过示差扫描量热分析和热重分析以及弯曲性能和吸水率测试研究了玻璃微珠含量对复合泡沫材料性能的影响。结果表明,玻璃微珠的加入促进了环氧与氰酸酯间的固化反应。加入玻璃微珠后,复合材料的最大热分解温度和玻璃化转变温度变化不大,但初始热分解温度略有下降。与纯树脂基体相比,复合材料的弯曲模量基本保持不变,但在玻璃微珠质量分数从5%增至10%时,弯曲强度急剧下降。此外,随着空心玻璃微珠含量的增加,复合泡沫材料的密度逐渐降低,吸水率逐渐增加。     

轻质环氧复合材料的制备与性能研究

制备了一种以空心玻璃微珠为填充材料的轻质环氧复合材料,确定了材料的固化工艺,并对不同型号的空心玻璃微珠进行了筛选.研究了玻璃微珠填充量对材料密度及力学性能的影响.研究发现,复合材料的密度随空心玻璃微珠填充量的加大呈现先降低后略有升高的趋势;拉伸强度和压缩强度均随填充量的增加而减小;拉伸弹性模量和压缩弹性模量随着填充量提...     

空心玻璃微珠对乘用车专用阻尼材料性能的影响

以含有机硅苯乙烯-丙烯酸酯共聚乳液(简称"苯丙乳液")为基料,制备了含有2种不同粒径空心玻璃微珠的复合阻尼材料。采用傅里叶红外光谱仪和动态力学分析仪研究了乳胶膜的化学结构、阻尼性能和玻璃化转变温度;通过扫描电子显微镜表征了乳胶粒的粒径分布以及复合阻尼材料中玻璃微珠的分布及破碎情况;采用漆膜冲击仪、电子万能试验机和自制的阻尼系数测定仪研究了不同型号及其不同配比的空心玻璃微珠对复合阻尼材料的力学性能以及阻尼性能的影响。结果表明,粒径大的空心玻璃微珠相比于粒径小的空心玻璃微珠更易破碎,且粒径小的空心玻璃微珠与基体界面黏结性更好;而混合添加则对阻尼性能的提高更有利;随着基体内部混合空心玻璃微珠中粒径较小的微珠的质量分数的提高,复合阻尼材料的冲击强度和拉伸强度随之增大;当大粒径和小粒径空心玻璃微珠的质量比为1:1,且其总含量为15%(质量分数,下同)时,复合阻尼材料的阻尼性能为最佳。     

空心玻璃微珠增强聚四氟乙烯复合材料的制备及拉伸强度的研究

研究了空心玻璃微珠增强聚四氟乙烯复合材料的拉伸强度的变化。研究表明：复合材料的拉伸强度与空心玻璃微珠含量、烧结工艺条件和偶联剂的种类有关;用复合偶联剂处理过的玻璃微珠填充树脂,改善了微珠与树脂的相容性及分散性,从而提高了材料的拉伸强度。并对材料的拉伸强度进行了理论预测。     

环氧树脂基固体浮力材料的研制及表征

采用空心玻璃微珠填充环氧树脂研制固体浮力材料。间苯二胺 (MPD)、顺丁烯二酸酐 (MA)、二氨基二苯砜(DDS)及 593四种固化剂对比研究表明,MPD和DDS环氧树脂固化体系轴向压缩强度可达 210MPa。γ 氨丙基三乙氧基硅烷(KH—550)偶联剂在无机玻璃微珠与有机环氧树脂的复合过程中,可增加环氧树脂与微珠之间的亲合,电镜照片观察到微珠与环氧树脂间无界面沟隙,粘结界面均匀。空心玻璃微珠质量填充量为 25%时,复合材料密度降低至 0. 61g/cm3,轴向压缩强度仍能保持在 40MPa以上。     

HGB/EP复合泡沫材料界面破坏模拟研究

空心玻璃微珠(HGB)/环氧树脂(EP)复合泡沫材料是一种新型的结构功能双重材料,其两种材料相互间的黏结性能对复合材料的力学性能有较大的影响。通过设计玻璃与环氧树脂的黏结力实验测得了黏结力与变形的关系。建立玻璃微珠与环氧树脂的数值模拟模型,采用实验所得数据在其间设置黏结单元,对六种情况下的模型施加拉伸和压缩均布载荷进行数值模拟,考察两种材料间界面的变形和破坏情况,研究了界面破坏时复合泡沫材料所受的极限载荷,分析了极限载荷随玻璃微珠半径及填充比的变化规律,发现其与相关文献实验结果一致。     

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。