马来酸三乙醇胺双酯的合成及其对水泥性能的影响

本文以马来酸酐、三乙醇胺为原料,通过两者酯化反应合成马来酸三乙醇胺双酯,探讨反应温度、反应时间、物料摩尔比对其酯化程度的影响规律;并考察合成产物在不同掺量下对水泥力学性能(强度)和水化特性(水化热、化学结合水、微观形貌)的影响.研究结果表明:反应温度120℃,反应时间4h及马来酸酐和三乙醇胺的摩尔比为1:2时,马来酸酐与三乙醇胺的酯化程度最高,酯化率高达80.22％;在此反应条件下合成的马来酸三乙醇胺双酯的掺量为0.02％时,对水泥的力学性能和水化性能作用效果最佳;与三乙醇胺相比,两者对水泥早期强度的作用相当,但马来酸三乙醇胺双酯对水泥后期水化有明显促进作用,对水泥后期强度的激发优于三乙醇胺.     

马来酸三乙醇胺酯对水泥水化的影响

为克服三乙醇胺早强剂对水泥抗折强度和后期强度的影响,合成了马来酸三乙醇胺酯,并通过背散射电子成像(BSE)和BET分析,研究了马来酸三乙醇胺酯对水泥水化程度、C-S-H含量和水泥水化28 d分形维数的影响。结果表明:马来酸三乙醇胺酯可促进水泥水化尤其是水泥中硅酸盐相的水化;复掺马来酸三乙醇胺酯和聚羧酸减水剂,可显著提高水泥水化产物中C-S-H的含量;三乙醇胺降低了水泥石28 d的分形维数,马来酸三乙醇胺酯单掺及与聚羧酸减水剂复掺则使水泥石28 d的分形维数提高。由此可见,马来酸三乙醇胺酯作为增强型水泥早强剂具有广阔的应用前景。     

三乙醇胺和三异丙醇胺对矿渣水泥水化过程的影响

采用三乙醇胺和三异丙醇胺作为矿渣水泥的助磨剂,通过测定水泥的颗粒特性、凝结时间、胶砂强度和化学结合水量,研究不同掺量的助磨剂对矿渣水泥水化过程的影响,并利用X射线衍射和扫描电镜分析,研究矿渣水泥水化产物的物相组成和显微结构.结果表明:两种助磨剂均能显著提高矿渣水泥的水化速率,使水泥浆体中生成更多的水化产物,形成更致密的结构,三异丙醇胺对矿渣水泥的增强效果优于三乙醇胺.     

助磨剂原材料三乙醇胺改性的试验研究

为降低助磨剂生产成本,对三乙醇胺进行改性试验。试验研究了三乙醇胺与硫酸配比及反应时间对改性三乙醇胺的助磨作用及对水泥性能的影响,得到最佳合成条件为TEA∶ H2SO4=1∶0.5（摩尔比）,合成时间4h。按此条件生产的改性产物比三乙醇胺作助磨剂水泥3d抗压强度提高2%,可以替代三乙醇胺用于助磨剂生产。通过成本测算,改性后的三乙醇胺成本降低20%,可使助磨剂成本降低1　000元/吨。     

几种水泥助磨剂对粉煤灰水泥性能的影响

本文就三种水泥助磨剂-三乙醇胺、三异丙醇胺和自制助磨剂对粉煤灰水泥性能的影响进行了实验探讨,对生产实践提供了参考.实验分别将三乙醇胺(TEA)、三异丙醇胺(TIPA)及实验室自制的自制助磨剂以0.03％～0.08％的不同比例添加到粉煤灰水泥中,通过胶砂实验测试水泥强度并结合XRD和SEM表征,分析三乙醇胺,三异丙醇胺和实验室自制助磨剂对水泥水化过程的影响.结果表明:三种助磨剂都对粉煤灰水泥有很好的增强作用,TEA增强主要表现在后期28 d,胶砂实验的水泥试块抗压强度提高了26.8％到33.4％;TIPA增强作用主要表现在前期3d,胶砂实验的水泥试块抗压强度提高了7.1％到22.2％;自制助磨剂早期3d和后期28 d增强效果都明显,胶砂实验的水泥试块3d抗压强度提高了4.6％到8.6％,28 d强度提高了24.4％到30.4％.XRD和SEM研究显示各助磨剂增强机理并不一样.     

合成助磨剂对钛矿渣水泥性能的影响

采用三异丙醇胺、二乙醇胺、丙烯酸、HPEG400等原料合成了一类新型水泥助磨剂,检测了对钛矿渣水泥的助磨效果、物理力学性能和水化产物的影响.结果表明,加入助磨剂后,钛矿渣水泥的比表面积提高了9.5%~14.7%,3 d和28 d抗压强度分别提高了9.0%~21.2%和7.2%~10.6%.XRD和TG/DTA的测试结果表明,新型助磨剂能促进水泥水化的进行,但并不会产生新的水化相.     

三乙醇胺硫酸酯盐助磨剂的制备及其性能评价

三乙醇胺是现在常用的水泥助磨剂,但是因其存在制取成本高、后期水泥强度有所降低等弊端[1],需要对其改性。本文用氨基磺酸对三乙醇胺进行硫酸化,合成三乙醇胺硫酸酯盐助磨剂。由于氨基磺酸反应温和,无副产物,同时也克服了浓硫酸硫酸化反应时易碳化反应物以及反应时添加硫酸铵缓冲剂难分离等缺点。改性后的助磨剂由于含有硫酸基强吸附性基团,改变了三乙醇胺单一的特点。同时还分析了合成的三乙醇胺硫酸酯盐助磨剂的助磨效果以及对水泥性能的影响。     

聚羧酸减水剂配制助磨剂对水泥性能的影响

试验利用聚羧酸减水剂与三乙醇胺复配作为水泥助磨剂,通过小磨试验研究助磨剂对水泥颗粒的粒度分布、抗压强度以及水泥的比表面积等因素进行研究,研究表明粒度分布因素与压强有着明显的关联;其中粒度在3μm~32μm的百分数越多其水泥的强度越大;聚羧酸减水剂助磨剂助磨生产水泥相比较空白水泥其各期龄抗折分别增加11.7%、8.81%、3.02%,抗压强度其分别增加7%、12.06%、5.4%;其中通过XRD对水泥水化产物CH进行研究:聚羧酸减水剂助磨剂促进水泥水化反应,提高水泥强度发展。     

改性三乙醇胺化合物的合成及其对水泥助磨性能的影响

本文合成了五种改性三乙醇胺化合物,即三乙醇胺硫酸酯(GA_1)、三乙醇胺乙酸酯(GA_2)、三乙醇胺马来酸酯(GA_3)、马来酸三乙醇胺盐(GA_4)和油酸三乙醇胺盐(GA_5).以三乙醇胺为参比项,在不同添加量下,各化合物与水泥熟料和石膏在闭路磨机内粉磨一定的时间,通过分析粉体的比表面积(SSA)、粒径分布、中值粒径(D_(50)) 、均匀性系数(n)和强度,探讨了改性后的三乙醇胺会对水泥助磨效果产生的影响,并分析了作用机理.结果表明,改性三乙醇胺的助磨效果优于三乙醇胺,其中马来酸三乙醇胺盐的助磨增强效果最佳.     

一种液体水泥助磨剂对水泥适应性的研究

从与水泥适应性的角度,通过激光粒度、水泥凝结时间、流动度、水泥胶砂抗压强度、SEM分析,系统地研究了一种自制液体水泥助磨剂对普通硅酸盐水泥、粉煤灰水泥、矿渣水泥物理化学性能的影响.结果表明:掺加助磨剂的普通硅酸盐水泥、矿渣水泥、粉煤灰水泥标准稠度用水量变化不明显,凝结时间明显缩短,对体积安定性无影响.该助磨剂提高了普通硅酸盐水泥、粉煤灰水泥、矿渣水泥的抗压强度.通过SEM发现助磨剂增加了普通硅酸盐水泥的水化产物,提高了水化反应速率.显著减小了粉煤灰水泥颗粒粒径,促进粉煤灰水泥的早期水化.增加了矿渣水泥水化产物,使得颗粒间隙更加密实.     

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。