活性硼酸锌的合成与表征

采用正交实验法探讨了以氧化锌和硼酸为原料、制备阻燃剂水合硼酸锌(2Zn0．3B2O3．5H2O)的最佳工艺条件，其最佳配比为ZnO：CH3BO3：H2O为10．9：61．8：360(质量比)；并在合成的过程中采用改性剂对其表面进行了改性，经偶联剂和阴离子表面活性剂改性后的硼酸锌，其表面由亲水性转为亲油性；同时采用红外光谱及热重分析对产品进行表征。     

微波辐射固相反应合成硼酸锌

以硫酸锌、硼砂为原料进行了微波辐射固相反应合成2375型硼酸锌(2ZnO·3B2O3·7.5H2O)的研究,探索出一种新的制备硼酸锌的工艺路线.实验考察了影响硼酸锌硼锌比[n(B2O3)/n(ZnO)]的因素,并对合成产品进行了表征.实验表明,微波辐射强度和原料配比对产品硼锌比有较大影响.通过差热分析,测定合成产品的失水温度为170～230℃,与2375型硼酸锌失水温度较接近;X射线衍射谱图的谱线位置和相对强度与7.5水硼酸锌的标准谱图相符;扫描电镜显示晶体为不规则形状,粒径1.5μm左右.     

硼酸锌粉体的氧化铝表面改性研究

为扩大硼酸锌的应用领域,采用氧化铝为表面改性剂对适合木材防腐杀菌剂用低水合硼酸锌(2ZnO·3B2O3·3.5H2O)进行表面包覆和改性.考察了氧化铝包覆量和水分等因素对产品流动性能和粒径的影响,确定了最佳工艺条件:氧化铝包覆质量分数为0.8%,水分质量分数为0.12%;并用激光粒度分析仪和热重-差热分析对样品进行了性能测定,改性产品的平均粒径为6.884 μm,脱水温度大于300 ℃;同时还对制备的改性硼酸锌样品和国外同类产品的性能进行了对比测试.实验结果表明,用氧化铝表面改性能减少硼酸锌粉末中粒径＞38 μm的粒子,提高硼酸锌的流动性和分散性.在木材防腐杀菌剂领域,硼酸锌有着广泛的应用前景.     

制备不同形貌的4ZnO·B_2O_3·H_2O型硼酸锌

本文介绍了水热法制备的硼酸锌(4ZnO·B_2O_3·H_2O)的合成方法及其性质。硼酸锌是一种新型、高效、无机无毒阻燃剂。为了改进制备硼酸锌的制备条件并研究其阻燃性能,以八水合五硼酸铵和七水合硫酸锌为原料,通过控制变量法优化实验条件,制备硼酸锌(4ZnO·B_2O_3·H_2O)。通过X-射线粉末衍射(XRD)、热重分析(TGA)及扫描电镜(SEM)对微米棒的组成、表面结构及形貌进行了分析。     

微波加热制备低水硼酸锌

以硼砂和硫酸锌为原料,研究了微波加热制备低水硼酸锌(2ZnO·3B2O3·3.5H2O)的工艺,考察了反应温度、液固质量比、微波辐射时间、微波功率等因素对硼酸锌产率和粒径分布的影响,通过优化实验,确定了最佳工艺条件.实验结果表明,在反应温度85℃,液固质量比3:1,微波辐射时间50 min,微波功率630 W的条件下可制备平均粒径为10.16μm的低水硼酸锌,产率达99.18%.同时采用XRD及TG分析对产品进行表征,XRD谱图与低水硼酸锌标准谱图吻合,TG分析显示产品脱水温度与低水硼酸锌的理论脱水温度接近.     

复合型改性无机阻燃剂在PVC中的应用

文章介绍了阻燃剂的阻燃作用及其分类,并综述了各种常用阻燃剂的阻燃机理。研究了稀土改性氢氧化镁(Mg(OH)2)、氢氧化铝(Al(OH)3)、三氧化二锑(Sb2O3)、硼酸锌(2ZnO·3B2O3·3.5H2O(ZB))、改性红磷为主的复合阻燃体系对糊状PVC阻燃性能的影响。通过氧指数测定仪对样品的氧指数测定,根据单因素分析寻找出复合无机阻燃剂的最佳配方。     

以工业副产锌泥水热合成硼酸锌及表面改性

以工业副产物锌泥及硼砂、硼酸为原料,150℃下水热反应3 h,制备水合硼酸锌(2Zn O·3B2O3·3H2O),样品呈长方体状,粒径约为3μm,并对所制备的硼酸锌进行XRD、TG-DTA、SEM、IR表征。以硬脂酸钠为改性剂,采用正交实验考察了改性剂用量、改性时间、改性温度等因素对硼酸锌改性的影响。结果表明,当硼酸锌的料浆质量分数为5%时,适宜的改性条件:硬脂酸钠用量为2%(质量分数)、前期磁力搅拌40 min、170℃下水热改性60 min。改性后样品的活化指数约为96%,亲油疏水;形貌由长方体开裂成片状,比表面积增大,更利于与高分子基材的融合。     

超细硼酸锌阻燃剂的制备及其性能研究

以硼砂和氯化锌为原料,研究了原料浓度、搅拌速度、乳化剂种类和用量等因素对硼酸锌粒径和粒径分布的影响。通过优化实验,制备了超细硼酸锌,数均平均粒径73nm,比表面积31.5m2/g,90%的粒子在纳米尺度范围。XRD衍射图与采用化学分析测定结果证明产物为低水硼酸锌(2ZnO.3B2O3.3.5H2O),电镜分析表明其晶体形貌为不规则的球形。将超细硼酸锌应用于聚氯乙烯,当硼酸锌用量为树脂质量的10%~30%,成炭率比未阻燃的聚氯乙烯大幅增加。表明超细硼酸锌在提高聚氯乙烯阻燃性的同时有很好的抑烟效果。     

CdS亚微米球的制备及性能研究

以Cd(NO3)2·4H2O为镉源,Na2S2O3·5H2O为硫源,采用水热合成法成功制备出CdS亚微米球.利用X射线衍射仪(XRD)和扫描电子显微镜(SEM),对得到的产物进行了表征,并利用紫外/可见(UV/Vis)分光光度计,对其光吸收性能进行了测试.结果表明,制备的亚微米球状CdS材料在可见光波段具有较好的光吸收...     

单分散Fe3O4亚微米球的粒径控制合成及表征

采用溶剂热还原法,以FeCl3.6H2O和乙二醇为原料,在200℃相对低温条件下成功合成四氧化三铁微米球。通过改变实验条件,可在115～435nm有效调控Fe3O4亚微米球的粒径。采用X射线衍射仪(XRD)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)对样品的结构、粒径、形貌和组成进行了分析,并于室温测试了它的磁学性能。结果表明,产物Fe3O4亚微米球为反尖晶石结构,330nmFe3O4亚微米球的矫顽力(Hc)为6644.93A/m,饱和磁化强度(Ms)为81.2emu/g,剩余磁化强度(Mr)为14.6emu/g。研究了乙二醇和NaOH的浓度、反应时间对产物形貌的影响,结果表明,乙二醇在Fe3O4亚微米球的形成过程中起着关键作用,并提出了可能的生长机理。     

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。