聚酰胺胺树形分子对羧基化聚乙烯的表面修饰

通过紫外光接枝方法,以丙烯酸为单体对低密度聚乙烯薄膜进行表面改性,然后用聚酰胺胺(PAMAM)分子对羧基化的聚乙烯表面进行修饰,制备了表面固定PAMAM树形分子的低密度聚乙烯薄膜。通过接触角测量,衰减全反射红外光谱,扫描电镜等方法的表征,证明丙烯酸成功接枝到聚乙烯薄膜表面,聚酰胺胺树形分子通过与羧基的结合形成团簇结构,反映了接枝链在薄膜表面的聚集状态。     

液相自组装Ce、W掺杂VO2薄膜的制备及其性能研究

利用三氯十八烷基硅烷(octadecyltrichlorosilane--OTS)为模板,以草酸、五氧化二钒,硝酸铈、钨酸铵、为原料,利用自组装薄膜技术,在玻璃基片上成功制备了氧化钒薄膜。测量了紫外光照射后OTS薄膜的亲水性。通过X射线衍射研究了自组装氧化钒薄膜的晶体结构,利用扫描电镜观察了薄膜的表面形貌,表明通过自组装制备的氧化钒薄膜通过退火处理后,可以良好的在玻璃基片上成膜,薄膜质量良好。通过FTIR测试表明,1%Ce和1.5%W共掺杂的VO2薄膜其相变温度从65℃降低到28℃。     

SiO2纳米粒子自组装膜的制备与表征

通过静电自组装技术在玻璃基底上组装了具备纳米尺度形貌的Al2O3 和SiO2 纳米粒子薄膜,采用液滴法测量其接触角,利用紫外-可见分光光度计测量其光学吸收特性,并利用原子力显微镜(atom force microscope, AFM)对两种纳米粒子薄膜及空白对比试片的表面结构进行了表征.结果表明,利用静电自组装原理在玻璃基片上组装的表面材料确实具备纳米形貌,且粗糙程度不同,具体为nano-Al2O3＞nano-SiO2＞CTAB＞control.这将为微生物细胞及动物细胞在纳米材料表面上的粘附考评实验做好准备.     

二苯胺型光敏重氮树脂光化学反应动力学研究方法初探

用动态红外、紫外光谱法研究了二苯胺型光敏重氮树脂在水溶液中光分解反应动力学，得到了二苯胺型光敏重氮树脂在水溶液中光分解反应速率方程、动力学方程及量子效率。     

聚乙烯醇缩丁醛薄膜老化机理研究

利用红外光谱和力学性能的变化研究了聚乙烯醇缩丁醛薄膜的热老化和紫外光老化机理,结果表明,在热老化及紫外光老化过程中,PVB薄膜的拉伸强度均是先增大然后再减小。这是由于在热老化过程中PVB薄膜发生了增塑剂的损失及PVB分子主链和侧链的断裂,而在紫外光老化过程中,主要是发生PVB分子链之间的交联反应,仅有少量的分子链发生断裂。PVB薄膜的光老化和热老化都是由树脂中存在少量聚醋酸乙烯分解生成的自由基诱导而发生的,添加适量的热稳定剂和紫外吸收剂可以吸收薄膜加工时生成的自由基,从而提高薄膜的稳定性及粘结性能。     

铁酸铋功能陶瓷薄膜的液相自组装制备

利用自组装单层膜技术,以三氯十八烷基硅烷(octadecyl trichlorosilane,OTS)为模板,以硝酸铋和硝酸铁为原料,在玻璃基片上成功制备了铁酸铋(BiFeO3)晶态薄膜。采用接触角仪测量了紫外光照射后OTS单层膜的亲水性。通过X射线衍射、扫描电镜和能谱仪等表征了BiFeO3薄膜的物相、表面形貌及微观结构。结果表明:紫外光照射使OTS单层膜由原来的强疏水性转变为良好的亲水性,说明OTS自组装膜层表面已被羟基化。在70℃沉积8h并经600℃退火2h制备的BiFeO3薄膜结晶良好,薄膜样品的表面平整,厚度较为均匀,薄膜厚度约为100nm。     

市场纵横

纳米紫外光屏蔽涂料开创高性能领域在紫外光屏蔽方面,作为重要的光学颜料,纳米TiO2的紫外光屏蔽特征一直受到广泛关注。因为用作涂料基料的高分子树脂受到太阳中紫外线的长期照射会导致分子链的降解,影响涂膜的物性,传统的紫外光吸收剂主要为有机物,但是有机紫外光吸收剂的寿命短、有毒,而纳米TiO2粒子是一种稳定的无毒的紫外光吸收剂。将无机纳米材料与树脂复合制备的涂层涂覆在固体表面,得到纳米级“褥垫”可以缓解原子或分子簇的高速冲击。该技术可以用来制备纳米级表面涂层。美国NSF最近也提出了一个有关项目申请,其要点是研究含无机…     

玻璃表面静电自组装TiO2基薄膜研究

采用静电自组装薄膜技术在玻璃基片表面上制备了TiO2基薄膜。研究TiO2基薄膜的光催化活性和超亲水性。     

铂纳米颗粒自组装膜的微图像化

从硝基重氮树脂(NDR)与包裹巯基乙酸的铂纳米颗粒(MA-PtNP)的静电自组装，制备了感光性的自组装多层超薄膜，经选择性紫外曝光和十二烷基硫酸钠(SDS)水溶液显影，光照部分的膜，因层与层之间的离子键转变为共价键，不再被SDS水溶液洗脱而留下来；未光照部分的膜，层与层之间仍是离子键，在显影时被除去，从而形成图像、用AFM和SEM对形成的图像进行了表征．     

聚乙烯管道电熔连接过程中的易发问题及质量控制

聚乙烯管道中的电熔连接,是将预埋了电热丝的电熔管件组装到聚乙烯管道元件上,连接时电热丝发热使管件与聚乙烯管路上的连接部位达到熔融状态,在聚乙烯树脂熔胀压力的作用下,使连接界面两侧的树脂分子重新绕结组合,冷却后达到连接目的的连接过程.电熔连接方式有电熔承插连接、电熔鞍形连接.本文将从电熔连接质量问题的现象入手,分析问题产生的原因,并阐述电熔连接施工过程中的质量控制.     

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.     

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.