用造纸黑液合成AA/AM高吸水树脂研究

以造纸黑液、丙烯酸(AA)、丙烯酰胺(AM)为原料,以过硫酸铵(APS)为引发剂,采用溶液聚合法制备了木质素接枝共聚丙烯酸-丙烯酰胺高吸水树脂;采用红外光谱对树脂进行了初步表征,测定了树脂的吸水性能;利用控制变量法研究了单体配比、丙烯酸中和度、引发剂用量、反应温度对树脂吸水倍率的影响;最佳合成条件为:NAM:NAA=0.2,AA中和度为60%,引发剂用量为0.1%,聚合温度为70℃,此时树脂对去离子水的吸水倍率为730g·g-1。     

喷雾干燥制备吸水树脂的研究

以喷雾干燥制备为主要工艺手段，探究单体浓度、中和度、引发剂、交联剂以及反应温度对吸水树脂产品性能的影响，主要考察对去离子水及生理盐水的吸收倍率，确定了丙烯酸单体占反应体系质量65%,中和度70%,引发剂过硫酸钾占反应体系质量0.45%,内交联剂N,N-亚甲基双丙烯酰胺占反应体系质量0.035%,反应温度140℃的最佳工艺参数，去离子水吸水倍率到达713g/g,生理盐水吸水倍率达到35g/g。     

麦秸秆纤维素与丙烯酸接枝共聚制备耐盐性吸水树脂的研究

应用小麦秸秆与丙烯酸接枝共聚制备了耐盐性吸水树脂,进行了结构表征,研究了单体配比、丙烯酸中和度、引发剂和交联剂用量以及反应温度对吸盐水倍率的影响。研究发现,接枝共聚的适宜条件为:丙烯酸单体与麦秸秆质量比为8∶1,丙烯酸中和度为70%,引发剂过硫酸钾-硫代硫酸钠的用量为单体的3.5%,交联剂N,N-亚甲基双丙烯酰胺用量为单体质量的0.24%,反应温度为70℃。在此条件下制备的树脂吸盐水倍率最高,吸盐水(CNaC l=0.9%)可达68 g/g,可应用于医疗卫生等方面。     

玉米淀粉接枝丙烯酸制备高效吸水树脂的研究

本文在紫外光照射下以芬顿试剂为引发剂,制备玉米淀粉接枝丙烯酸高效吸水树脂。通过单因素法考察了中和度、淀粉与丙烯酸质量比、交联剂及引发剂用量等因素对反应的影响,并通过红外光谱分析仪(FT-IR)对产品结构进行表征。实验结果表明:在N2保护下淀粉乳浓度为5.88%,丙烯酸与淀粉的质量比为1.3∶1,引发剂用量和交联剂用量占淀粉的质量百分数分别为5.00%和2.00%,聚合温度为40℃,聚合反应时间为1h,中和度为65%,所制备淀粉吸水树脂的吸水倍率可达到631g·g-1。     

有机改性凹凸棒土复合P (AA-co-AM)高吸水性树脂的制备及性能研究

以过硫酸铵为引发剂,表面丙烯酰基化的凹凸棒土(AT-MPS)为交联剂,采用水溶液聚合法制备了丙烯酰基化凹凸棒土复合聚(丙烯酸-co-丙烯酰胺)高吸水性树脂[AT-MPS/P (AA-co-AM)].考察了中和度、丙烯酸与丙烯酰胺的单体比、引发剂用量以及凹凸棒土用量对复合吸水树脂吸液性能的影响.采用红外光谱(FTIR)、热失重分析(TGA)以及扫描电镜(SEM)等方法对复合吸水树脂进行了表征.结果表明,丙烯酸中和度为75％、m(AA)∶m(AM) =4∶1、引发剂用量为0.8％、AT-MPS用量为8％时,复合吸水树脂的最大吸水倍率为347.7 g/g,最大吸盐水倍率为43.5 g/g.红外光谱分析结果表明,凹凸棒土参与了聚合交联反应;SEM表明,凹凸棒土在复合吸水树脂中具有良好的分散性.     

耐盐性高吸水树脂的合成及性能研究

以N,N-亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,采用水溶液聚合法合成了耐盐性聚丙烯酸钠-co-丙烯酰胺高吸水树脂.研究了单体配比、丙烯酸中和度、引发剂、交联剂以及反应温度和烘干成型温度对吸盐水倍率和吸盐水速率的影响.对其结构以及外观形貌进行了表征.合成的高吸水树脂吸蒸馏水的倍率为1 390 g/g,吸盐水倍率为95 g/g.     

玉米秆制取吸水树脂的研究

以玉米秆为原料制取羧甲基纤维素钠,与丙烯酸接枝共聚制备吸水树脂.讨论了单体配比、丙烯酸中和度、交联剂用量及引发剂用量等因素对吸水性能的影响.实验发现,在丙烯酸单体与玉米秆质量比为8∶1、丙烯酸中和度为70%、交联剂N,N-亚甲基双丙烯酰胺为丙烯酸单体质量的0.24%、引发剂过硫酸钾为丙烯酸单体质量的3.5%、反应温度为60℃的条件下,所得树脂吸水倍率最高可达68 g/g.     

水溶液聚合法制备P(AA-AMPS-HPEG-2400)高吸水树脂

以丙烯酸,2-丙烯酰胺-2-甲基丙磺酸,甲基烯丙基聚氧乙烯为三元聚合单体,N,N-亚甲基双丙烯酰胺为交联剂,过硫酸钾引发,用水溶液聚合法制备了P(AA-AMPS-HPEG-2400)高吸水树脂。研究了单体配比,引发剂,交联剂,中和度和温度对树脂吸液性能的影响,并通过正交实验探讨了各因素对吸液倍率影响的强弱。结果表明,最佳反应条件为单体配比为10∶3∶1,中和度为75%,引发剂用量为0.8%,交联剂用量为0.07%,反应温度65℃,制得的高吸水树脂吸蒸馏水倍率达到893 g/g,吸生理盐水的倍率达到93 g/g。     

反相悬浮聚合法制备超强吸水树脂

以环己烷作为分散介质,以司班80作为分散荆,N,N-亚甲基双丙烯酰胺和多元醇作为交联剂,过硫酸铵作为引发剂采用反相悬浮聚合法分两阶段合成了核壳型超强吸水树脂,得到的产品呈颗粒状,吸去离子水倍率为998g／g,吸生理盐水的吸液倍率达到147g／g。探讨了分散荆、交联剂、反应温度、丙烯酸中和度及核壳比对超强吸水树脂物理状态及吸液能力的影响。     

蒙脱土改性三元共聚高吸水树脂制备与性能研究

以酸处理有机蒙脱土为改性剂,采用水溶液聚合法制备蒙脱土改性丙烯酸基三元共聚高吸水性树脂。在丙烯酸∶丙烯酰胺∶烯丙基磺酸钠单体质量配比为8∶4∶0.5,中和度70%,反应温度75℃,交联剂用量为单体的0.1%,引发剂用量为单体的0.18%和有机蒙脱土用量为单体的4%条件下,所制得树脂的吸水倍率、吸生理盐水倍率和吸人工尿液倍率分别为735.6,58.5,46.6 g/g。     

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。