高光泽度丙烯酸酯乳液的制备及性能

以自制固体碱溶性丙烯酸酯树脂(A-30)为大分子表面活性剂、甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸丁酯(BA)为软单体、丙烯酸(AA)为功能单体和N-羟甲基丙烯酰胺(NMA)为交联单体,采用半连续乳液聚合法合成了性能优良的纸张上光油用水性丙烯酸酯乳液。研究结果表明:当m(MMA)∶m(BA)=40∶56~45∶51、w(NMA)=3%(相对于总单体质量而言)以及w(A-30)=30%~50%(相对于乳液质量而言)时,乳液及其胶膜的综合性能良好,其硬度、附着力、储存稳定性、光泽度、耐磨性、耐水性及耐溶剂性俱佳,并且胶膜经有机溶剂擦拭22次后仍不掉色。     

高固含量丙烯酸酯微乳液的研究

以甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸丁酯(BA)为软单体、丙烯酸(AA)和N-羟甲基丙烯酰胺(NMA)为功能性单体以及过硫酸铵(APS)-亚硫酸氢钠为引发剂,合成了固含量为45%左右的丙烯酸酯微乳液。研究结果表明:普通乳化剂[烷基酚醚磺基琥珀酸酯钠盐(OS)、十二烷基硫酸钠(SDS)]、反应性乳化剂[烯丙氧基羟丙磺酸钠(HAPS)]、NMA和反应温度等对合成的丙烯酸酯微乳液性能有影响;当反应温度为80～85℃、w(OS)=4.2%、w(SDS)=2.2%、w(HAPS)=0.5%和w(NMA)=0.50%时,合成的丙烯酸酯微乳液的综合性能较好。     

自交联型涂料印花黏合剂的制备与性能研究

以甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸丁酯(BA)为软单体、丙烯酸(AA)为功能单体、N-羟甲基丙烯酰胺(NMA)为交联单体、过硫酸铵(APS)为引发剂、十二烷基硫酸钠(SDS)和壬基酚聚氧乙烯醚(NP-40)为复合乳化剂,采用预乳化半连续乳液聚合法合成了自交联型丙烯酸酯涂料印花黏合剂。研究结果表明:当m(MMA)∶m(BA)=0.38∶1、w(NMA)=3%、w(AA)=2.5%～3.0%、w(复合乳化剂)=3.0%且m(SDS)∶m(NP-40)=1∶(1.5~2.0)、w(APS)=0.8%、75~80℃聚合3 h和85℃保温1 h时,相应乳液的综合性能相对最好。     

PHMS/BA/VAc共聚乳液的研究

采用乳液滴加法将含氢聚甲基硅氧烷(PHMS)、丙烯酸丁酯(BA)和醋酸乙烯酯(VAc)进行乳液共聚,制得了稳定的PHMS／BA,／VAc聚合物乳液。讨论了PHMS和N-羟甲基丙烯酰胺(NMA)的用量对聚合物乳液的表面张力、离心稳定性及粒径大小的影响。结果表明：随着PHMS用量的增加,乳液的表面张力减小,平均粒径增大,稳定性提高;随着NMA用量的增加,平均粒径增大,在一定用量范围内,聚合物乳液的离心稳定性提高。     

亲水单体对聚氨酯丙烯酸复合乳液性能的影响

采用种子乳液聚合法,以甲苯二异氰酸酯(TDI)、聚醚二元醇(N210)、二羟甲基丙酸(DMPA)和甲基丙烯酸甲酯(MMA)为主要原料合成了聚氨酯丙烯酸(PUA)复合乳液。考察了DMPA对PUA乳液的制备和性能的影响;确定了DMPA的添加工艺及中和度。发现随DMPA添加量增加,PUA乳液的外观变好,乳液粒径变小,乳液黏度增大,乳液凝胶量降低,稳定性变好。随DMPA添加量增大,PUA乳液涂膜的吸水率增大,涂膜的耐水性越差。综合得到w(DMPA)=7 5%,采用后添加DMPA的工艺,且DMPA的中和度90%～100%,可得到性能优异的PUA复合乳液。     

水性发用聚丙烯酸定型树脂的合成及性能

以丙烯酸(AA)、丙烯酰胺(AM)、甲基丙烯酸二甲氨基乙酯(DMAEMA)和丙烯酸丁酯(BA)为聚合单体,N-羟甲基丙烯酰胺(NMA)为交联剂,采用溶液聚合法制备了水性发用聚丙烯酸定型树脂,并应用于配制睹喱.探讨了单体组成和交联剂用量对树脂性能的影响.当m(AA):m(AM):m(DMAEMA):m(BA)=1.0:0.07:0.07:0.15,NMA用量为单体总质量的0.06%时,制得树脂无色透明,w=10%水溶液表观黏度2042 mPa·s;配制成睹喱后,卷曲保持率为73%,梳理时基本无白屑.     

含双丙酮丙烯酰胺(DAAM)的水性乳液的制备与性能研究

通过预乳化乳液聚合工艺,合成了含官能团单体双丙酮丙烯酰胺(DAAM)、丙烯酰胺、N-甲基丙烯酰胺(NMA)的自交联丙烯酸酯乳液。实验结果表明,DAAM用量的增加对乳液涂膜的硬度有影响,而涂膜的耐水性随NMA用量增加有显著提高,在DAAM用量为单体含量的2％,NMA用量为单体含量的4％时,涂膜的铅笔划痕硬度达2H,耐水性达96h以上。     

聚丙烯酸酯涂料印花黏合剂的合成与性能研究

以过硫酸铵(APS)为引发剂、甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸丁酯(BA)和丙烯酸异辛酯(EHA)为软单体、丙烯酸(AA)为功能单体和N-羟甲基丙烯酰胺(NMA)为交联单体,采用预乳化法合成出一种聚丙烯酸酯涂料印花黏合剂。讨论了单体滴加方式、预乳化液滴加时间、阴/非离子型乳化剂配比及用量、交联剂和各单体用量等对该黏合剂乳液性能的影响。结果表明:当w(BA)=15%、w(EHA)=8%、w(MMA)=20%、w(NMA)=3.0%、滴加时间为2.5 h、复合乳化剂中m(SDS):m(OP-10)=1:2且w(复合乳化剂)=6%时,该黏合剂乳液具有优良的综合性能,能够满足织物印花的使用要求。     

自交联含氟丙烯酸酯共聚物乳液的制备

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)等为主要单体,甲基丙烯酸六氟丁酯(HFMA)为含氟单体,N-羟甲基丙烯酰胺(NMA)为交联单体,采用种子乳液聚合法制备了自交联含氟丙烯酸酯共聚物乳液。研究了HFMA、NMA、复合乳化剂(SDS OP-10)、引发剂(KPS)用量、聚合温度、聚合时间和搅拌速度等因素对聚合反应最终转化率和乳液稳定性的影响,结果表明在m(MMA)∶m(BA)=1∶1及搅拌速率210 r/min条件下,HFMA、NMA、SDS OP-10和KPS加入量分别为总单体量的7%、3%、3%和0.5%(均为质量分数),以及聚合温度75℃、反应时间4 h时,制备得到的乳液单体总转化率高,乳液凝聚率低,聚合反应稳定,涂膜的综合性能优良。此外,含氟乳胶膜的FT-IR及TG-DSC分析结果表明,HFMA有效地参与了共聚反应,提高了涂膜的耐热性。     

一种铁杉改性拼板胶的研制

为得到一种性能优异的铁杉拼板胶,以多亚甲基多苯基多异氰酸酯(PAPI)为交联剂,对N-羟甲基丙烯酰胺(NMA)改性聚醋酸乙烯酯(PVAc)乳液胶的性能进行测试。结果表明:(1)利用NMA改性PVAc乳液,可以有效提高耐水性;(2)在NMA改性PVAc乳液胶的基础上,加入少量交联剂PAPI,可以显著提高湿状剪切强度。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.