废旧PU硬泡的降解及其与PP共混物的性能研究

采用二乙醇胺为降解剂对废旧聚氨酯(PU)硬泡进行降解处理,制备了降解PU/聚丙烯(PP)共混材料;研究了不同降解程度的PU硬泡对PU/PP/PP-g-MA共混材料性能的影响。结果表明:随着降解时间的增加,PU硬泡的凝胶的质量分数由91.4%下降到3.6%,降解产物的玻璃化转变温度由75℃下降到36℃;FTIR证明了降解产生了带有氨基和羟基基团的PU,这些基团成为反应增容的活性点;PU/PP/PP-g-MA复合材料的断裂伸长率由100%上升到1800%,SEM表明复合材料具有有良好的均匀性和相互作用。     

淀粉/WPUR生物可降解塑料的制备与性能

以玉米淀粉与水性聚氨酯(WPUR)为主要原料,以甘油为增塑剂,采用熔融共混工艺制备了生物可降解热塑性淀粉塑料(TPS)/WPUR共混物。考察了TPS/WPUR共混物的微观结构、成型加工性能、力学性能和耐水性能等。结果表明,WPUR不仅有利于TPS的塑化和改善其熔体流动性,而且也有利于提高其拉伸性能和耐水性。     

制备条件对胺改性纳米ZnO光催化性能的影响

采用有机胺化合物对溶胶-凝胶法制备的纳米ZnO进行改性。以紫外灯作为光源,以甲基橙水溶液为光催化反应模型降解物,研究胺改性后ZnO的光催化性能。并通过考察改性剂的量、凝胶温度、恒温搅拌时间及煅烧温度对改性纳米ZnO光催化性能的影响,确定最适宜的胺改性ZnO的制备条件。试验结果表明,二乙醇胺作为改性剂的效果较好,其最适宜制备条件为:二乙醇胺的掺杂量为n(二乙醇胺)/n(ZnO)为0.50,凝胶温度为80℃,凝胶老化时间1.5 h,煅烧温度500℃。此时,甲基橙降解率与未经过改性的ZnO相比提高了1倍。     

废弃聚氨酯硬泡的回收再利用研究

以废弃聚氨酯硬泡为原料,研究了降解条件对降解效果的影响以及降解产物对开孔型聚氨酯硬泡性能的影响。具体考察了醇解剂、胺解剂、催化剂对硬泡溶解能力和产物特性的影响,以及再生多元醇的羟值、用量对泡沫开孔率和尺寸稳定性等的影响。结果表明：使用固体酸催化并采用先醇解后胺解的方式可有效降解板材废泡,降解所得再生多元醇的羟值为550～800 mgKOH/g,用量占组合聚醚质量分数的10%～40%时,可获得性能优良的开孔型聚氨酯硬泡。     

废旧聚酯纺织品的热降解动力学

通过分析废聚酯纺织品的组分、黏度、含水率,并与常规聚酯切片对比,证明其由纯聚酯纤维布料组成,黏度低而杂质含量高。在氮气气氛下采用热失重分析测试布泡料和常规聚酯切片的热降解参数,发现布泡料的起始分解温度和最大分解速率温度都低于常规聚酯切片。用Kissinger法分析常规聚酯切片和白布泡料的热降解动力学,样品的ln(β/T2max)和1000/Tmax之间均呈现良好的线性关系,说明Kissinger方程可以很好地表述其热降解过程。计算发现白布泡料的活化能和指前因子均低于常规聚酯切片。     

催化剂对废旧PU硬泡回收再利用的影响

用含有小分子醇的交联剂和催化剂使废旧聚氨酯（PU）硬泡进行降解能够获得多元醇,将降解料与聚醚多元醇、催化剂和发泡剂共混以制备白料,然后与黑料异氰酸酯混合均匀,得到再生PU硬泡。通过对降解产物的黏度、羟值以及获得的再生PU硬泡材料的密度、强度、吸水率、热稳定性、扫描电子显微镜、红外光谱和热失重等进行测试分析,得出了催化剂添加量对废旧PU材料回收再利用的影响因素。结果表明,催化剂（KOH）用量为0.9 g时废旧PU的降解效果最好,获得的再生PU硬泡的密度为37.6 kg/cm³,压缩强度为164.2 kPa,热导率为0.015 24 W/（m·K）,吸水率为0.429 5 %。     

复合烯胺溶液吸收CO2降解实验研究

目前关于烯胺复合溶液降解的研究较少,而烯胺与N-甲基二乙醇胺(MDEA)复合溶液具有吸收容量大、吸收速率快的特点,已在胜利油田碳捕集测试平台进行了中试研究,具有较好的推广前景。研究讨论了20:5三乙烯四胺(TETA)/MDEA和20:4四乙烯五胺(TEPA)/MDEA热降解与氧化降解的降解率变化,分析了两者降解过程中CO_2负载、温度、铁离子的影响,研究表明增加CO_2负载、温度和Fe~(3+)会增大20:5 TETA/MDEA、20:4 TEPA/MDEA热降解和氧化降解程度,铁离子(Fe~(3+))在降解过程中起到了催化作用。     

微/纳米材料对聚氨酯硬泡性能影响的研究

以聚醚/聚酯多元醇、多异氰酸酯(粗MDI)、微/纳米材料和助剂等原料制成复合聚氨酯硬泡。对复合聚氨酯硬泡进行表征,并研究了微/纳米材料对聚氨酯硬泡性能的影响。结果表明,微/纳米材料对聚氨酯硬泡的泡孔结构有改善作用,对聚氨酯发泡时物料的流动性、硬泡的尺寸稳定性及压缩强度有一定的影响,加入纳米Fe3O4的发泡体系流动性变好,纳米Bi2O3使得硬泡的压缩强度增加。微/纳米材料的添加对聚氨酯硬泡的热分解温度有一定的影响,并能有效降低聚氨酯硬泡的导热系数。     

水性聚氨酯/聚乙烯醇复合纳米纤维的制备及结构研究

将水性聚氨酯(WPUR)与聚乙烯醇(PVAL)按照不同质量比制备质量分数为8%的纺丝溶液,通过静电纺丝制备WPUR/PVAL复合纳米纤维。运用扫描电子显微镜、傅立叶变换红外光谱仪和X射线衍射仪对WPUR与PVAL质量比不同的纺丝溶液制备的复合纳米纤维的微观形貌和结构进行分析。实验结果表明,PVAL的含量对复合纳米纤维的形成和形貌起着决定性的作用,随着溶液中PVAL含量的增加,纺丝过程中纺丝液逐渐从不连续复合纳米纤维转变为连续均匀的复合纳米纤维,纤维直径逐渐增大,当纺丝液中WPUR与PVAL的质量比为30∶70时,得到的复合纳米纤维形貌最佳,其平均直径为330.8 nm,具有最小标准差,为22 nm,同时随着纺丝溶液中PVAL含量的增加,所得复合纳米纤维的结晶性能增强。     

助剂对全水发泡阻燃聚氨酯硬泡性能的影响

采用聚醚多元醇、多异氰酸酯、泡沫稳定剂、液态阻燃剂、催化剂和水制备了全水发泡阻燃硬质聚氨酯泡沫塑料,研究了水用量、催化剂、泡沫稳定剂及阻燃剂对聚氨酯硬泡性能的影响。结果表明,水用量影响聚氨酯硬泡的泡沫密度、压缩强度、尺寸稳定性、吸水率等性能;不同催化剂复配影响聚氨酯硬泡的泡孔结构;泡沫稳定剂影响泡孔均匀性和聚氨酯硬泡的导热性能;磷酸三乙酯(TEP)对硬泡阻燃性能的影响优于磷酸三氯丙酯(TCPP)和阻燃聚醚多元醇(F-7190)。随TEP用量的增加,聚氨酯硬泡的氧指数增大,压缩强度降低;随F-7190用量增加,聚氨酯硬泡的氧指数略有增大,压缩强度先增大后变小。     

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。