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941.
In this work, we synthesized a novel organic–inorganic semitelechelic polymer from polyhedral oligomeric silsesquioxane (POSS) and poly(acrylate amide) (PAA) via reversible addition‐fragmentation chain transfer (RAFT) polymerization. The organic–inorganic semitelechelic polymers have been characterized by means of nuclear magnetic resonance spectroscopy, thermal gravimetric analysis, and dynamic mechanical thermal analysis. It was found that capping POSS groups to the single ends of PAA chains caused a series of significant changes in the morphologies and thermomechanical properties of the polymer. The organic–inorganic semitelechelics were microphase‐separated; the POSS microdomains were formed via the POSS–POSS interactions. In a selective solvent (e.g., methanol), the organic–inorganic semitelechelics can be self‐assembled into the micelle‐like nanoobjects. Compared to plain PAA, the POSS‐capped PAAs significantly displayed improved surface hydrophobicity as evidenced by the measurements of static contact angles and surface atomic force microscopy. More importantly, the organic–inorganic semitelechelics displayed typical shape memory properties, which was in marked contrast to plain PAA. The shape memory behavior is attributable to the formation of the physically cross‐linked networks from the combination of the POSS–POSS interactions with the intermolecular hydrogen‐bonding interactions in the organic–inorganic semitelechelics. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 587–600 相似文献
942.
Molecular bulks are favorable for the thermal and morphological stability in organic wide-bandgap semiconducting polymers with potential applications in both information and energy electronics. In this review, we present our progress in the design of fluorene-based bulky semiconductors with a fractal four-element pattern. Firstly, we established one-pot methods to spirofluorenes, especially spiro[fluorene-9,9′-xanthene](SFX) serving as the next-generation spiro-based semiconductors. Secondly, we observed the supramolecular forces at the bulky groups and discovered the supramolecular steric hindrance(SSH) effect on polymorphisms, nanocrystals as well as device performance. Thus, a synergistically molecular attractor-repulsor theory(SMART) was proposed for the control of nanocrystal morphology, thin film phase and morphology. Thirdly, the third possible type of defects has been identified to generate green band(g-band) emission in widebandgap semiconductors by the introduction of molecular strain design of cyclofluorene. Finally, the first bulky polydiarylfluorene with highly crystalline and β conformation was achieved by an attractor-repulsor design of tadpole-shape monomer, which offered an effective platform to fabricate stable wide-bandgap semiconducting devices. All the discoveries offer the solid basis to break through bottlenecks of organic/polymer wide-bandgap semiconductors by the improvements of overall performances. 相似文献
943.
We present a microwave-assisted one-pot polymerization with three-components of alkynes, aldehydes and amines for the synthesis of new amino-functionalized optoelectronic polymers. The polymerization of diynes(1a-1c), dialdehydes(2a and 2b) and dibenzylamine catalyzed by InCl_3 was carried out smoothly within 1h under microwave radiation, yielding four soluble polymers with high molecular weights. The resulting polymers P1 and P2 could be easily dissolved in alcohol and thus utilized as the cathode interlayer for polymer solar cells(PSCs). Compared with the control device, the PSCs with P1 and P2 as the cathode interlayer and PTB7-Th:PC_(71)BM as the photoactive layer exhibited significantly higher power conversion efficiencies(PCEs) of 9.49% and 9.16%, respectively. These results suggest that this polycoupling reaction is an efficient approach to construct three-component polymers for the practical applications. 相似文献
944.
柱后衍生HPLC法测定功能饮料中的牛磺酸 总被引:1,自引:0,他引:1
建立柱后衍生–高效液相色谱法测定功能性饮料中牛磺酸的含量。功能性饮料中的牛磺酸经水溶提取后与邻苯二甲醛柱后衍生,以柠檬酸三钠溶液(p H 3.2)为流动相,用AMINO–NA色谱柱分离,荧光检测器检测,激发波长为338 nm,发射波长为425 nm,柱后衍生反应温度为55℃,流量为0.4 m L/min。牛磺酸质量浓度在5.0~25.0μg/m L范围内与色谱峰面积线性关系良好,r=0.999 8,检出限(S/N=3)为0.11μg/m L,测定结果的相对标准偏差为0.73%(n=6),加标回收率在99.2%~101.6%之间。该方法灵敏度高、选择性好,可用于市售功能性饮料中牛磺酸的测定。 相似文献
945.
Chen Haijun Wang Youqun Zhao Wuwei Xiong Guoxuan Cao Xiaohong Dai Ying Le Zhanggao Zhang Zhibin Liu Yunhai 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(1):175-189
Journal of Radioanalytical and Nuclear Chemistry - The graphene oxide (GO) was functionalized with phosphate groups and applied as an effective adsorbent for the removal of uranium from aqueous... 相似文献
946.
Accurate Theoretical Study of LiS Radical and Its Singly Charged Cation and Anion in their Ground Electronic State 下载免费PDF全文
Potential energies of LiS(2Π), LiS-(1Σ+) and LiS+(3Σ-) are calculated by using the multireference configuration interaction method including Davidson correction and the augmented correlation-consistent basis sets aug-cc-PV(X+d)Z (X=T, Q). Such obtained potential energies are subsequently extrapolated to the complete basis set limit. Both the core-valence correction and the relativistic effect are also considered. The analytical potential energy functions are then obtained by fitting such accurate energies utilizing a least-squares fitting procedure. By using such analytical potential energy functions, we obtain the accurate spectroscopic parameters, complete set of vibrational levels and classical turning points. The present results are compared well with the experimental and other theoretical work. 相似文献
947.
Numerical Investigation on 1,3-Butadiene/Propyne Co-pyrolysis and Insight into Synergistic Effect on Aromatic Hydrocarbon Formation 下载免费PDF全文
Tian-yu Li Jia-biao Zou Yan Zhang Chuang-chuang Cao Wei Li Wen-hao Yuan 《化学物理学报(中文版)》2017,30(3):287-294
A numerical investigation on the co-pyrolysis of 1,3-butadiene and propyne is performed to explore the synergistic effect between fuel components on aromatic hydrocarbon formation.A detailed kinetic model of 1,3-butadiene/propyne co-pyrolysis with the sub-mechanism of aromatic hydrocarbon formation is developed and validated on previous 1,3-butadiene and propyne pyrolysis experiments.The model is able to reproduce both the single component pyrolysis and the co-pyrolysis experiments,as well as the synergistic effect between 1,3-butadiene and propyne on the formation of a series of aromatic hydrocarbons.Based on the rate of production and sensitivity analyses,key reaction pathways in the fuel decomposition and aromatic hydrocarbon formation processes are revealed and insight into the synergistic effect on aromatic hydrocarbon formation is also achieved.The synergistic effect results from the interaction between 1,3-butadiene and propyne.The easily happened chain initiation in the 1,3-butadiene decomposition provides an abundant radical pool for propyne to undergo the H-atom abstraction and produce propargyl radical which plays key roles in the formation of aromatic hydrocarbons.Besides,the 1,3-butadiene/propyne co-pyrolysis includes high concentration levels of C3 and C4 precursors simultaneously,which stimulates the formation of key aromatic hydrocarbons such as toluene and naphthalene. 相似文献
948.
The interactions between AgnO-(n=1-8) and H2 (or D2) were explored by combination of the mass spectroscopy experiments and density function theory (DFT) calculations. The experiments found that all oxygen atoms in AgnO-(n=1-8) are inert in the interactions with H2 or D2 at the low temperature of 150 K, which is in contrast to their high reactivity with CO under the same condition. These observations are parallel with the preferential oxidation (PROX) of CO in excess hydrogen catalyzed by dispersed silver species in the condensed phase. Possible reaction paths between AgnO-(n=1-8) and H2 were explored using DFT calculations. The results indicated that adsorption of H2 on any site of AgnO-(n=1-8) is extremely weak, and oxidation of H2 by any kind of oxygen in AgnO-(n=1-8) has an apparent barrier strongly dependent on the adsorption style of the "O". These experiments and theoretical results about cluster reactions provided molecule-level insights into the activity of atomic oxygen on real silver catalysts. 相似文献
949.
Huang Yun Liu Bo Cao Haijun Lin Yuanhua Tang Shuihua Wang Mingshan Li Xing 《Journal of Solid State Electrochemistry》2017,21(8):2291-2299
Journal of Solid State Electrochemistry - One novel cage kind of polyhedral ligomeric silsesquioxane (POSS), for modification application of gel polymer electrolyte (GPE) in lithium ion batteries... 相似文献
950.