水性聚氨酯/纳米二氧化钛复合材料的制备和表征

以聚己内酯二元醇(PCL)、聚乙二醇(PEG)和异佛尔酮二异氰酸酯(IPDI)为主要原料合成了稳定的水性聚氨酯(WPU)乳液,再用钛酸四丁酯制备了可再分散的纳米Ti O2粉末,采用物理混合法制备了WPU/纳米Ti O2复合材料。讨论了Ti O2含量对材料力学和耐水性能的影响,并采用X射线衍射(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)和紫外可见分光光度计(UVVis)对材料进行表征。结果表明,当Ti O2质量分数为2%时,复合材料力学性能最好,拉伸强度增加了37.35%,断裂伸长率增大了11.03%;并且复合材料的吸水率降低,抗水解性能提高;在光照条件下可完全降解罗丹明B。     

氧化石墨烯增强聚氨酯阻燃及力学性能的研究

为提高聚氨酯(PU)材料的阻燃及力学性能,采用熔融共混的方法制备了含磷阻燃剂的氧化石墨烯/聚氨酯(GO/PU)复合材料。分析了GO/PU复合材料的微观结构及燃烧后碳层的形貌,研究了GO的用量对GO/PU复合材料阻燃性能及其老化前后力学性能的影响。结果表明:随着GO用量的增加,GO/PU复合材料的阻燃性能逐渐增加,加入5%的GO时,LOI值达到39.8%,垂直燃烧等级为V-0级;加入含磷阻燃剂后,GO/PU复合材料力学性能有所下降;添加GO后,对GO/PU复合材料的力学性能起到增强的作用,复合材料的耐老化性能也随着GO含量的增加而提高。     

天然黑色素改性聚氨酯及紫外遮蔽线性能的研究

采用聚氨酯与天然黑色素通过物理共混制备得到聚氨酯/天然黑色素复合材料(PU/M),主要研究了不同天然黑色素含量对聚氨酯的紫外遮蔽性能和力学性能的影响。结果表明,天然黑色素的引入,明显提高聚氨酯的紫外遮蔽性能,当质量分数2%时,亚甲基蓝溶液仅降解22%;同时天然黑色素赋予聚氨酯更佳优异的力学性能,当质量分数1%时,力学性能达到最佳。     

木塑复合材料耐光老化性对篮球架的影响研究

木塑复合材料有着绿色环保、延展性强、硬度高等优势,可运用于室外篮球架的材料制作,任何材料都存在老化、氧化的问题,影响篮球架的适用范围。以木粉/聚丙烯复合材料为例,研究了木粉组分和亚磷酸三酯（抗氧化剂168）2个因素对木塑复合材料耐光老化性能的影响,阐述了木塑复合高分子材料耐光老化性保护对篮球架的作用。实验表明：木质素有助于复合材料的力学性能保持,纤维素可促进复合材料光老化过程中的颜色稳定性;当VE质量分数为0.2%、抗氧化剂168质量分数为l. 0%时,复合材料的耐光老化性能最佳。复合材料耐光老化性能的改善有助于进一步扩大材料的其他性能优势。     

聚氨酯海绵改性环氧树脂复合材料的摩擦学性能研究

以聚氨酯（PU）海绵作为三维支撑材料,吸附氧化石墨烯（GO）和石蜡（PW）,制备了改性环氧树脂（EP）复合材料。对该复合材料进行摩擦学性能测试,结果表明：当PW质量为PU的3.5倍时,复合材料的摩擦系数最小,相比纯EP摩擦系数降低了57.77%;当PW质量为PU的2.5倍时,复合材料的比磨损率最低,相比纯EP比磨损率降低了94.08%。采用扫描电子显微镜对复合材料的磨损表面进行表征,认为GO和PW的协同作用对改善复合材料的摩擦学性能起着关键作用。     

聚氨酯/甲基二苯基氧化膦的冷结晶及阻燃性能研究

将新型阻燃剂甲基二苯基氧化膦（DPMP）与聚氨酯（PU）复合,并采用片状黏土为协效剂,通过极限氧指数（LOI）测试、垂直燃烧测试（UL 94）和微型量热分析（MCC）研究了DPMP和黏土对复合材料阻燃性能的影响,并采用示差扫描量热仪（DSC）、热失重分析仪（TG）分析了复合材料的结晶性能及热降解行为。结果表明,DPMP能促进PU冷结晶,从而提高其模量和力学性能。当PU复合材料中DPMP含量（质量分数,下同）为10%时,PU的LOI值从23%增加到28.3%。PU/10%DPMP的模量、断裂伸长率和拉伸强度分别为1.37 MPa、1 042%和13.84 MPa,纯PU的相应分别为1.17 MPa、811%和11.32 MPa。当体系进一步加入黏土,1%的黏土即可使PU/DPMP的滴落现象消失,UL 94达到V-0级。     

形状记忆剑麻微晶/聚氨酯复合材料的制备与性能（英文）

用剑麻微晶(MCFs)作为交联剂制备了交联型形状记忆聚氨酯(PU)复合材料,考察了MCFs含量不同的MCFs/PU复合材料的力学性能及形状记忆性能。结果表明,MCFs/PU复合材料的力学性能随MCFs含量的增加而明显提升。在MCFs质量分数为0.75%时复合材料具备最佳的力学性能,拉伸强度和扯断伸长率比纯PU可分别提高约80%和500%;同时可赋予MCFs/PU复合材料暂时形变并加热诱导其形状记忆,形状回复率最高可达96%,形状记忆性能优异。     

MC尼龙／Sm2O3纳米复合材料的制备及性能研究

用原位分散聚合法制备了一系列MC尼龙/Sm2O3纳米复合材料,并对其结构和力学性能进行了表征.结果表明,纳米Sm2O3使MC尼龙晶格尺寸发生了一定程度的改变;纳米Sm2O3的加入可以明显改善MC尼龙的力学性能,对MC尼龙同时具有增强和增韧双重效果;MC尼龙/Sm2O3纳米复合材料的力学性能随着纳米Sm2O3用量的增加呈先升高后降低的趋势.当纳米Sm2O3的质量分数为0.5%时,复合材料的拉伸强度和断裂伸长率达到最大值,分别比MC尼龙提高了18.8%和91.5%,当纳米Sm2O3的质量分数为1.0%时,复合材料的缺口冲击强度、穹曲强度和弯曲弹性模量达到最大值,分别比MC尼龙基体提高了36.6%、11.2%和11.5%.     

纳米Al2O3填充PTFE复合材料的制备及性能研究

通过机械搅拌和超声分散制备了纳米Al2O3填充聚四氟乙烯(PTFE)复合材料。研究了Al2O3用量、表面改性等因素对复合材料密度、硬度、力学性能、摩擦磨损等性能的影响。结果表明:当改性Al2O3的质量分数小于5%时,复合材料的拉伸强度、硬度要高于相同用量未改性Al2O3填充的复合材料;对改性Al2O3,当其质量分数为1%和9%时,复合材料的磨耗量较纯PTFE分别下降了55倍和286倍,而对未改性Al2O3,当其质量分数为1%和9%时,复合材料的磨耗量较纯PTFE分别下降了7倍和420倍;复合材料的密度与Al2O3的用量,表面是否经KH560改性关系不大;复合材料的摩擦因数随Al2O3用量的增加先减小后增大,对未改性Al2O3,当其质量分数为1%时,复合材料具有最低摩擦因数,而对于改性Al2O3,当其质量分数为3%时,复合材料具有最低摩擦因数。     

石墨烯/聚氨酯复合热界面材料的制备与性能研究

采用原位聚合法,分别以氧化石墨烯(GO)和多层石墨烯为填料,制备了石墨烯/聚氨酯(PU)复合热界面材料。对比了两种石墨烯对聚氨酯弹性材料的补强作用,研究了GO用量对GO/PU复合材料力学性能、导热性能和热稳定性的影响。结果表明:在相同用量下,氧化石墨烯对聚氨酯弹性材料的补强作用好于多层石墨烯; GO质量分数为1. 5%时,复合材料的力学性能最佳,导热系数和热失重5%时的热分解温度达到最大。     

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。