precise synthesis and variation in the thermoresponsive property based on the supramolecular assembly of a novel urea end-functionalized poly(N-isopropylacrylamide) (PNIPAM) were studied. A series of PNIPAMs with diff...
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A new triphenylamine-containing aromatic diamine monomer, N,N-bis (4-aminophenyl)-N,N-bis(4-tert-butylphenyl)-1,4-phenylenediamine, was synthesized by an established synthetic procedure from readily available reagents...
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A new triphenylamine-containing aromatic diamine monomer, N,N-bis (4-aminophenyl)-N,N-bis(4-tert-butylphenyl)-1,4-phenylenediamine, was synthesized by an established synthetic procedure from readily available reagents. A novel family of electroactive polyamides with di-tert-butyl- substituted N,N,N,N-tetraphenyl-1,4-phenylenediamine units were prepared via the phosphorylation polyamidation reactions of the newly synthesized diamine monomer with various aromatic or aliphatic dicarboxylic acids. All the polymers were amorphous with good solubility in many organic solvents, such as N-methyl-2-pyrrolidinone (NMP) and N,N-dimethylacetamide, and could be solution-cast into tough and flexible polymer films. The polyamides derived from aromatic dicarboxylic acids had useful levels of thermal stability, with glass-transition temperatures of 269-296 °C, 10% weight-loss temperatures in excess of 544 °C, and char yields at 800 °C in nitrogen higher than 62%. The dilute solutions of these polyamides in NMP exhibited strong absorption bands centered at 316-342 nm and photoluminescence maxima around 362-465 nm in the violet-blue region. The polyamides derived from aliphatic dicarboxylic acids were optically transparent in the visible region and fluoresced with a higher quantum yield compared with those derived from aromatic dicarboxylic acids. The hole-transporting and electrochromic properties were examined by electrochemical and spectro-electrochemical methods. Cyclic voltammograms of the polyamide films cast onto an indium-tin oxide-coated glass substrate exhibited two reversible oxidation redox couples at 0.57-0.60 V and 0.95-0.98 V versus Ag/AgCl in acetonitrile solution. The polyamide films revealed excellent elcterochemical and electrochromic stability, with a color change from a colorless or pale yellowish neutral form to green and blue oxidized forms at applied potentials ranging from 0.0 to 1.2 V. These anodically coloring polymeric materials showed interesting electroch
Most existing iterative learning control (ILC) algorithms work in direct pattern; while indirect ILC is an open problem. In this paper, model predictive control (MPC) is chosen as the local controller for processes an...
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Most existing iterative learning control (ILC) algorithms work in direct pattern; while indirect ILC is an open problem. In this paper, model predictive control (MPC) is chosen as the local controller for processes and ILC is used to update the setpoint for MPC; this novel combination belongs to indirect ILC and is named ILC-based MPC in this paper. Indirect ILC has revealed some advantages compared to direct ILC. The proposed algorithm is validated in artificial pancreatic beta-cell and the simulation results verify the effectiveness and excellence of this method.
A series of blends of poly(lactic acid) (PLA) and poly(Ε-caprolactone) (PCL) with different mass ratio were prepared by means of the melt blending method to study their crystallization, miscibility, morphology, and t...
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＜正＞Organic solar cells are one of hot issues of research because of many strong points against inorganic solar cells,although they have low efficiency of *** has been known that the active polymer morphology and de...
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＜正＞Organic solar cells are one of hot issues of research because of many strong points against inorganic solar cells,although they have low efficiency of *** has been known that the active polymer morphology and degree of crystallinity greatly influences the efficiency. In this study,we prepared thin films based on poly（3-hexylthiophene）（P3HT）/phenyl-C60-butyric
Volatile organic compounds (VOCs) are the main factors involved in pollution control and global warming in industrialized nations. Various treatment methods involving incineration, adsorption, etc., were employed to r...
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Flower-like structures of ZnO was synthesised by solution method using zinc acetate dihydrate and sodium hydroxide. Hydroxylamine hydrochloride (0.4M and 0.8M) was used as a structure directing agent. Structural morph...
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Octaaminophenyl polyhedral oligomeric silsesquioxane (OapPOSS) was prepared as nanofillers and filled to isotactic polypropylene (PP). Maleic anhydridegrafted PP (MAPP) was selected as compatibilizer. The morphology, ...
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Octaaminophenyl polyhedral oligomeric silsesquioxane (OapPOSS) was prepared as nanofillers and filled to isotactic polypropylene (PP). Maleic anhydridegrafted PP (MAPP) was selected as compatibilizer. The morphology, crystallization, melting behavior and rheologcial behavior of PP/OapPOSS composites with or without MAPP were studied by scanning electron microscopy, differential scanning calorimetry, polarized optical microscope, oscillatory and capillary rheological analysis. The results showed that the morphology, crystallization and rheological behavior of the composites were strongly influenced by the existence of MAPP. MAPP improves the compatibility between PP and OapPOSS because of the reaction of OapPOSS with MAPP. The OapPOSS retards the crystallization of PP while promoting it when MAPP is added. MAPP could decrease the viscosity of PP/OapPOSS probably due to the weaker particle-particle interaction and interface slipping.
A thermodynamic model was developed to understand the role of charge compensation at the interlayer interfaces in compositionally graded monodomain ferroelectric multilayers. The polarization mismatch between the ferr...
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A thermodynamic model was developed to understand the role of charge compensation at the interlayer interfaces in compositionally graded monodomain ferroelectric multilayers. The polarization mismatch between the ferroelectric layers generates depoling fields with the polarization in each layer varying from its bulk uncoupled value as to adapt to the electrical boundary conditions. By treating the strength of the electrostatic field as a phenomenological parameter, it is shown that if there are localized charges to compensate for the polarization mismatch and relax the depolarization fields, ferroelectric layers behave independently of each other and exhibit a dielectric response that can be described as the sum of their corresponding intrinsic uncoupled dielectric properties. For perfectly insulating heterostructures with no localized charges, the depolarization field is minimized by lowering the polarization difference between layers, yielding a ferroelectric multilayer that behaves as if it were a single ferroelectric material. There exists an optimum value of coupling strength at which average polarization of the multilayer is maximized. Furthermore, ferroelectric multilayers may display a colossal dielectric response dependant upon the interlayer electrostatic interactions.
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