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合成了单体甲基丙烯酸-2-(9,9-二乙基)芴甲酯(FMMA)作为捕光天线分子,通过原子转移自由基聚合方法(ATRP)合成了以β-环糊精(β-CD)为核的21臂星形发光聚合物β-CD-g-(PFMMA-b-PDMAEMA)21作为捕光聚合物.通过氢核磁共振谱、基质辅助激光解析电离飞行时间质谱和凝胶渗透色谱对其结构进行了表征.将其与能量受体分子蒽包合,通过紫外-荧光测试检测到了两者的能量传递现象,成功证明了基于主客体包合作用的星形拓扑分子捕捉和传递能量的过程,在光敏器件、太阳能电池和有机发光二极管等领域内具有潜在的应用价值. 相似文献
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用Monte Carlo方法模拟了DMF溶剂体系中单组分芳氧基钇引发剂Y(OAr)3引发丙烯腈溶液聚合的全程反应动力学.通过计算机模拟和实验验证,表明聚合反应过程中存在配位阴离子活性中心,且活性中心容易形成,但很快失活.同时,存在向单体转移和向大分子转移两种链转移反应.获得了一组聚合反应动力学参数:ki=0.053 L/(mol.m in),kp=1.63 L/(mol.m in),kd=0.005 8 m in-1,ktM=0.052 L/(mol.m in),ktrP=0.075 L/(mol.m in),kpp=0 L/(mol.m in). 相似文献
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研究了苄胺引发N-取代甘氨酸-N-硫代羧酸酐(NNTA)开环聚合.聚合对引发剂当量的水(100~600μg/g)具有很好的耐受性,能保持良好的可控性,聚类肽产率高(>70%),分子量可控(1600~7500),分子量分布较窄(1.13~1.25).随着水含量的增加(达到单体当量)(14000μg/g),聚合产率与产物分子量均有不同程度的下降.MALDI-To F质谱证明所得聚类肽均为苄胺引发产物,水不能引发NNTA聚合.聚合动力学实验表明该聚合体系表现出准一级动力学反应的特征,在不同单体转化率时,聚合物数均分子量与单体转化率呈线性关系,分子量分布窄,证明该聚合体系具有可控性.进一步地,使用未经除水精制处理的市售THF溶剂和未经烘烤除水的反应瓶进行NNTA聚合反应,也表现出很好的可控性.NNTA单体易合成、易储存,聚合时不受微量水的影响,极大地降低了聚类肽的合成难度,有利于聚类肽材料的推广与应用. 相似文献
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Three-dimensional(3-D) coarse-grained Monte Carlo algorithms were used to simulate the conformations of swollen hydrogels formed by copper(I)-catalyzed azide-alkyne cycloaddition(Cu AAC). The simulation consists of three successive steps including diffusion, cross-linking and relaxation. The cross-linking of multifunctional reaction sites is simulated instantly followed by fast crosslinking. In order to explore the validity of this approach pristine poly(ethylene glycol)(PEG) hydrogels with tri- and tetra-functional reaction sites(G3 and G4 respectively) were prepared and characterized. The data from the simulations were found to be in good agreement with experimental results such as PEG lengths between crosslinks, pore volume and pore radius distribution, indicating the validity of the modeling algorithm. The calculated PEG lengths in G3 and G4 networks are close(≈ 4.6 nm). The 3-D visual topological structure of the hydrogel network suggests that the ideal hydrogel is far from cubic, diamond or any well defined structures of regular repeating cells. 相似文献
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It is reported that alkali-metal borohydrides(MBH4, M = Li, Na and K) are efficient catalysts for ring opening polymerization(ROP) of α-amino acid N-carboxyanhydrides(NCAs). Polypeptides are prepared in quantitative yields with relatively narrow molecular weight distributions(MWDs = 1.1~1.5) which depend on the reaction temperature. End groups of the produced polypeptide are studied in detail by MALDI-ToF MS, 1H-NMR, 13C-NMR, 1H-1H COSY and 1H-13C HMQC analyses. The results indicate that α-hydroxy-ω-aminotelechelic polypeptides are formed which are suitable for postpolymerization functionalization. 相似文献
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Algorithm and application of Monte Carlo simulation for multi-dispersive copolymerization system 总被引:1,自引:0,他引:1
A Monte Carlo algorithm has been established for multi-dispersive copolymerization system, based on the experimental data of copolymer molecular weight and dispersion via GPC measurement. The program simulates the insertion of every monomer unit and records the structure and microscopical sequence of every chain in various lengths. It has been applied successfully for the ring-opening copolymerization of 2,2-dimethyltrimethylene carbonate (DTC) with δ-caprolactone (δ-CL). The simulation coincides with the experimental results and provides microscopical data of triad fractions, lengths of homopolymer segments, etc., which are difficult to obtain by experiments. The algorithm presents also a uniform frame for copolymerization studies under other complicated mechanisms. 相似文献
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在凝胶色谱(GPC)测试高聚物分子量和分子量分布的实验基础上, 建立了一个共聚合多分散体系的Monte Carlo计算机仿真算法, 模拟共聚合过程中每个单体链节的形成, 记录每条长度不等的高分子链的链节结构和微观序列分布. 应用于2,2-二甲基三亚甲基环碳酸酯(DTC)和e-己内酯(ε-CL)开环共聚合的高分子链链节结构研究中, 模拟结果较好地重现了实验数据, 并提供了三元组分布、均聚链链节长度等难于从实验测定的微观信息. 本算法为研究复杂机理的多链共聚合体系提出了仿真框架. 相似文献