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1.
通过聚氨酯丙烯酸酯(PUA)预聚物中的端-NCO与双酚F型环氧丙烯酸酯(BPF-EA)低聚物中的侧-OH反应,制备了一种光活性聚氨酯改性环氧丙烯酸酯(PMEA)低聚物。将两种低聚物与活性稀释剂以及光引发剂均匀混合并进行了UV固化。研究了EA和PMEA低聚物及固化膜的性能。结果表明,制备的BPF-EA低聚物与自制的双酚A型环氧丙烯酸酯低聚物相比黏度大幅下降。EA和PMEA固化膜具有高的交联密度、良好的附着力以及优异的耐化学品性能。由于PUA预聚物的引入,聚合物链中具有一定量的柔性基团,PMEA固化膜的铅笔硬度、热稳定性和拉伸强度略有下降,断裂伸长率明显增加。固化膜的柔韧性变好。其中,以20%(质量分数)TPGDA为稀释剂配制的UV固化涂料,固化膜的综合性能最好。  相似文献   

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用环氧丙烯酸酯与聚氨酯丙烯酸酯共混聚合的方法制备出性能优良的UV固化光纤带涂料。讨论了齐聚物种类,齐聚物共混配比,不同官能度单体配比,齐聚物与单体的配比以及光引发剂及其含量对UV固化光纤带涂料的性能如剥离性、拉伸强度、延伸率和柔韧性的影响。  相似文献   

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用马来酸酐和聚乙二醇合成具有反应活性端基的聚乙二醇(PEG-MAH),并用其对环氧丙烯酸酯(EA)进行物理共混改性,测定了改性环氧丙烯酸酯固化膜的性能.试验结果表明,反应性聚乙二醇参与了环氧丙烯酸树脂的固化反应,提高了环氧丙烯酸树脂的冲击强度和附着力,但耐热性、耐酸碱性和耐水性降低.讨论了不同用量的反应性聚乙二醇(PEG-MAH)对涂膜性能的影响,结果表明加入20%用量的PEG-MAH涂层具有较好的综合性能.  相似文献   

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SiO_2消光剂(UV55C)对环氧豆油丙烯酸酯性能的影响   总被引:3,自引:0,他引:3  
谢慕华  耿云华 《化学世界》2002,43(7):356-358
考察了 Si O2 消光剂 (UV5 5 C)对环氧豆油丙烯酸酯及其涂膜性能的影响。试验结果表明 :Si O2 消光剂 (UV5 5 C)的加入 ,降低了环氧豆油丙烯酸酯的固化速率和其涂膜的光泽度 ,但提高了其涂膜的硬度、耐磨性和附着力  相似文献   

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UV固化环氧丙烯酸酯涂料研究进展   总被引:3,自引:0,他引:3  
综述了UV固化环氧丙烯酸酯的合成与改性,介绍了反应温度、原料配比、催化剂及阻聚剂的影响;改性主要是针对降低黏度,增加柔韧性,提高耐热、阻燃等性能。介绍了光引发剂及活性单体的研究进展,最后对光固化技术的发展趋势进行了展望。  相似文献   

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UV-光固化光纤涂料的研制   总被引:8,自引:0,他引:8  
本文采用环氧丙烯酸酯与聚氨酯丙烯酸酯共混聚合的方法制备出新型的UV.光固化光纤涂料,其主要性能较好.研究了基体组成、引发剂、稀释剂以及固化工艺对UV-固化光纤涂料的光固化速度的影响.通过实验发现,环氧丙烯酸酯与聚氨酯丙烯酸酯的配比为4:6~6:4、稀释剂的含量不大于20%时固化速度较快、性能较好,同时固化时灯距与固化膜厚度对固化速度的影响较大.  相似文献   

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201107058钢板防护涂层用含环氧和氨基甲酸酯丙烯酸酯树脂的可UV固化透明树脂组合物: 本发明涉及一种可UV固化树脂组合物,其含有:25%~45%(质量分数,下同)改性环氧丙烯酸酯低聚物和1O%~25%氨基甲酸酯丙烯酸酯低聚物。本发明可提供一种透明金属板,其具有耐腐蚀性、耐冲击性、耐刮伤性、附着性、抗腐蚀性以及可弯曲性(加工性),方法是在金属材料(如钢材,尤其是钢板)表面使用了本发明的可UV固化树脂组合物形成涂膜。  相似文献   

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通过共混法在聚对苯二甲酸乙二酯(PET)中添加光扩散剂制备PET光扩散膜。利用Mie散射理论计算了光扩散剂颗粒的折射率和粒径对光扩散效果的影响,并通过实验对理论计算结果进行验证。结果表明,光扩散剂颗粒折射率对光扩散效果的影响较小,而颗粒粒径的影响较大,与理论计算结果相吻合。探讨了光扩散剂添加量对光扩散效果的影响和原因,制备出透光率为85.3%、雾度为90.86%的PET光扩散膜。  相似文献   

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本文综述了UV固化环氧丙烯酸酯的合成和改性。改性主要是针对降低黏度,增加柔韧性,提高硬度、耐热、耐磨、阻燃等性能,最后对光固化技术的发展趋势进行了展望。  相似文献   

10.
UV光固化环氧丙烯酸酯耐磨涂料的研究   总被引:2,自引:0,他引:2  
石玉  李昕  穆鹏征 《中国生漆》2005,24(2):21-24
以E51和E44环氧树脂和丙烯酸为原料,制备了UV固化环氧丙烯酸酯耐磨涂料。不同光引发剂、稀释剂和助剂等对UV固化环氧丙烯酸酯涂料固化性能均有影响。研究结果表明,用安息香乙醚与二苯甲酮(质量比为2∶1)的混合体系作为光引发剂的引发效率最高,最佳涂料配方:环氧丙烯酸酯∶丙烯酸丁酯∶安息香乙醚∶二苯甲酮∶滑石粉为70∶20∶4∶2∶4(质量比)。  相似文献   

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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.  相似文献   

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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.  相似文献   

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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.  相似文献   

15.
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.  相似文献   

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Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.  相似文献   

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