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81.
将甲基丙烯酸缩水甘油酯(GMA)、丙烯酸(AA)、马来酸酐(MAH)3种不同单体分别通过开炼机剪切加入废旧轮胎粉(GRT)后与聚氯乙烯(PVC)直接反应挤出,制备了3种PVC/GRT复合材料。利用万能电子试验机测定了材料的力学性能,实验结果表明:3种不同单体修饰的GRT/PVC复合材料中PVC/GRTg-GMA复合材料韧性提高显著,在GRT用量为5 phr,GMA、St、DCP用量分别为4、4、0.15 phr时,PVC/GRT复合材料缺口冲击强度提高25.6%。扫描电镜结果显示GMA的加入改善了界面相容性。 相似文献
82.
以甲基丙烯酸二甲氨基乙酯(DM)和环氧氯丙烷(ECH)为主要原料,合成了一种活性体O-甲基丙烯酰-氧乙基二甲基环氧丙基氯化铵(ODEAC)。采用单因素实验分别讨论了反应溶剂、反应温度、物料比及反应时间对产物的转化率和环氧值的影响,确定了最佳合成工艺为:反应温度60℃,反应溶剂为异丙醇,物料比n(ECH)∶n(DM)=1∶1.6,反应时间4 h,在该条件下目标产物的转化率可达91.67%。并采用傅里叶变换红外光谱仪(FTIR)和核磁共振波谱仪(1HNMR)对产物结构进行了表征。 相似文献
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85.
The microstructures of the porous ceramics are improved considerably using polymethyl methacrylate (PMMA) as a pore template since particles tend to adsorb irreversibly at the air-water interface. This paper presents a versatile approach for the production of porous SiO2 ceramics by a process of direct foaming with the addition of PMMA beads. The adsorption free energy of the colloidal suspension was found to be 2.0?×?109?kT. A wet foam stability of >80% was achieved using the surfactant hexylamine (0.05?M), which resulted in a colloidal suspension with the highest surface tension (116.2?mN?m??1). 相似文献
86.
以硅基底和光纤纤芯阵列为定位夹具,手工排列熔凝法得到的Au微球,获得3×3 Au微球阵列;在Au微球表面先用水浴法合成ZnO纳米线、后固定葡萄糖氧化酶,得到球形跨尺度阵列葡萄糖酶电极。对球形跨尺度结构的表面形貌、葡萄糖氧化酶的固定效果、酶电极的电化学性能进行了定量表征。球形跨尺度结构阵列葡萄糖传感器的线性范围为0~2.5mmol/L、灵敏度为17.24μA·(mmol/L)~(-1)·cm~(-2)、最低检出限为3.44μmol/L、Michaelis-Menten常数为1.85 mmol/L。 相似文献
87.
Shi Dongjian Sui Jing Duan Fang Chen Mingqing He Bingxiao 《Reactive and Functional Polymers》2013,73(8):1015-1021
Thermal-sensitive poly(N,N-diethylacrylamide) grafted poly(acrylonitrile/styrene) (PDEAm-g-PAN/PSt) polymeric microspheres were prepared from PDEAm macromonomer, St and AN by dispersion copolymerization. The polymeric microspheres had raspberry-like morphology with large surface area. Palladium–metal (Pd–M) (M: copper, Cu, silver, Ag) bimetallic nanoparticles were stabilized on the surface of the PDEAm-g-PAN/PSt microspheres via the coordinate interaction between amide groups in PDEAm and metal ions with the reduction of the corresponding ions. Transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and thermogravimetry analysis (TGA) results confirmed the size and composition of the immobilized Pd–M nanoparticles. The Pd–M bimetallic nanoparticles showed superior catalytic efficiencies for the reduction of 4-nitrophenol (4-NP) than the monometallic nanoparticles. The catalytic activity of the Pd–M bimetallic catalysts could be controlled by the molar ratio of Pd and M ions and composition of Pd–M nanoparticles. Moreover, the catalytic property of the Pd–M nanoparticles could be regulated by temperature and increased with increasing the temperature above lower critical solution temperature (LCST). Furthermore, the Pd–M nanoparticles could be easily recycled and reused to catalyze 4-NP for five times without loss of activity. These bimetallic nanoparticles possess great potential in future practical application in catalytic technology. 相似文献
88.
Câtâlina Ioan Maria Bercea Jean-Louis Vernet Bogdan C. Simionescu 《Polymer-Plastics Technology and Engineering》2013,52(2):255-266
The article presents some Theological results obtained on a large domain of shear rates for semidilute solutions of ultrahigh-molecular-weight poly(methyl methacrylate) at different concentrations. The observed unusual behavior was explained as being due to the flow instabilities of long-chain polymers in an entangled state. 相似文献
89.
Atsunori Nozoe Minoru Abe Keisuke Ohto Hidetaka Kawakita 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(11):1374-1378
BACKGROUND: The formation of polyphenol microspheres by the polymerization of 3‐methylcatechol was performed in a methanol/phosphate buffer solution using horseradish peroxidase (HRP), without the use of a surfactant or a water/oil interface, to be used for germanium recovery. RESULTS: The polyphenol microspheres were of diameter 1 mm. The functional group density of phenol group in the polymer was approximately 15 mol kg?1 determined by the Folin‐Denis method. In batchwise experiments, the amount of germanium adsorbed was 0.23 mol kg?1. CONCLUSION: Because germanium is a rare metal, a system for its recovery is required. Using the proposed system, continuous recovery of germanium can be achieved using multilayered microspheres. Copyright © 2011 Society of Chemical Industry 相似文献
90.
In this paper it is shown that elastic properties of a poly(methyl methacrylate) melt in the linear range of deformation are more significantly influenced by the addition of silica nanoparticles than viscous ones. The effect is the strongest in the steady-state which is reached at several thousand seconds. That is the reason why the often used dynamic-mechanical experiments are not a very suitable method for investigations of that kind. Therefore, creep and creep-recovery tests were applied for the characterisation of the filled materials. The linear steady-state recoverable compliances following from the recovery experiments increase by a factor of 6 at the highest measured volume content of 2.1%. This finding is explained by the existence of long retardation times in the filled materials resulting from interactions between the fillers and matrix molecules attached to their surfaces which reduce their molecular mobility. Retardation spectra calculated from the recovery curves quantify these assumptions. The model is supported by the experimental finding that the recoverable compliance becomes smaller above a certain stress applied and approaches that of the matrix as such a behaviour could be explained by a detachment of the molecules from the particle surface. The paper demonstrates that investigations of elastic properties of nanoparticle filled polymers in the molten state at long experimental times are a very sensitive tool to get an insight into interactions between particles and macromolecules of such systems. 相似文献