含芘苯乙烯／二乙烯苯共聚物的合成与表征

本文首次通过共聚方法和功能基化方法合成了芘标记苯乙烯／二乙烯苯共聚物，用稳态荧光光谱、裂解色谱、裂解色谱－质谱等方法对芘标记共聚物进行了详细地表征。结果表明，通过控制芘标记单体的投料或功能基化反应时间，可以将一定量的芘基标记到苯乙烯／二乙烯苯共聚物中，其荧光光谱显示了芘基的单体荧光发射和激基缔合物荧光发射；共聚物裂解色谱的甲基芘峰和苯乙烯三聚体峰反映了芘基和交联聚苯乙烯骨架的特征，据此可建立甲基芘     

含不同取代芘基团St/DVB交联树脂的合成及其溶胀态光物理性质

采用功能基化反应和单体共聚两种方法合成了一系列含有Py-CO-基团和Py-CH2-基团的芘标记苯乙烯/二乙烯基苯(St/DVB)交联树脂及其相应的含芘模型化合物.通过比较分析共聚物珠体和模型化合物的荧光光谱,研究了交联树脂溶胀态的光物理行为.初步研究结果表明,标记基团的激基缔合物形成及Ham效应等光物理性质可敏感地反映树脂中标记的浓度、微环境极性以及树脂的溶剂化程度.     

一些新的芘衍生物的合成及光物理研究

本文合成了一系列新的芘衍生物，用紫外光谱和稳态荧光光谱方法研究了它们的光物理性质。结果表明，取代烷基几乎不影响芘的吸收光谱，而使芘的荧光光谱振动精细结构消失或部分消失；取代甲酰基的芘衍生物的荧光发射强烈依赖于溶剂的性质，极性溶剂中荧光光谱无精细结构，且荧光发射峰随介质极性的增加而红移。     

含芘苯乙烯/二乙烯苯共聚物的光物理研究

本文首次用稳态光谱法研究了含芘苯乙烯/二乙烯苯共聚物的光物理行为。结果表明,当共聚物中芘基的摩尔百分数低于0.006％时,其荧光光谱仅呈现芘基的单体荧光,并伴随以0—0发射谱带强度降低和精细振动结构的部分消失;当芘基的含量高于0.3％时,共聚物的荧光相继出现在420,440和475nm处的发射谱带。这一结果可归因于芘基各种基态和激发态聚集体的形成,集中地反映了交联共聚物凝聚态的非均匀性。     

荧光探针法研究壳聚糖水凝胶形成过程及其性能

基于芘(Py)单体荧光光谱结构对微观环境变化的敏感性,以及介质粘度及Py分子间距对Py激基络缔合物形成的影响,以戊二醛交联壳聚糖(CS)水凝胶体系为例研究了Py荧光探针法监测水凝胶形成过程及其溶胀性能的可行性。结果表明,Py荧光光谱精细结构的变化(以I~3/I~1为参量)或Py激基缔合物荧光强度与单体荧光强度之比(I~E/I~M)的变化与CS水凝胶的形成及溶胀程度有很好的对应关系。此外,CS凝胶网状结构中包埋的聚N-异丙基丙烯酰胺(PNIPAM)的构象变化也可由探针光谱变化反映出来。利用这种荧光探针方法有助于从分子水平上探知凝胶形成过程的微观本质。此外,这种方法也可作为光纤传导监测凝胶形成过程和溶胀的基础。     

4,4‘—偶氮二（4氰基戊酰对甲苯胺）的合成及其用作嵌段共聚合引发剂

合成了一类新型的含偶氮基和对甲苯基氨基甲酰基的多功能引发剂，４，４’偶氮二（４氰基戊酰对甲苯胺）．测定其偶氮键热分解反应为一级反应，分解活化能为１２４６ＫＪ·ｍｏｌ－１．利用引发剂中对甲苯氨基甲酰与Ｃｅ（ＩＶ）盐的氧化还原引发单体聚合，得到含有偶氮端的预聚物，它在６５℃热分解引发另一单体聚合生成嵌段共聚物．纯化后的共聚物，经ＩＲ等结构表征为嵌段共聚物     

一种含芘葡萄糖衍生物的合成及其胶凝行为

合成并表征了一种荧光活性小分子胶凝剂——芘磺酰基-丙二胺-葡萄糖(PSDAPG), 考察了其在36种常见溶剂中的胶凝行为. 结果发现, PSDAPG可使其中16种溶剂胶凝. 对癸醇, PSDAPG表现出罕见的超级胶凝能力, 室温下最低胶凝浓度(MGC)达7.0×10-4 g·mL-1. 此外, PSDAPG还是一种既可胶凝水又可胶凝有机溶剂的双性胶凝剂. 扫描电镜(SEM)、傅立叶变换红外光谱(FTIR)、核磁共振(1HNMR)和荧光光谱研究表明,在不同溶剂中, PSDAPG具有不同的聚集结构, 除了芘基之间的疏水π-π堆积作用外, 氢键作用是PSDAPG自发形成三维网络结构的重要驱动力. 实验研究还表明, 溶液态和凝胶态的PSDAPG荧光光谱均同时呈现芘的单体荧光和激基缔合物荧光光谱特征, 但两者的光谱形貌差异显著. 随凝胶的形成, 体系单体荧光发射增强, 激基缔合物荧光发射减弱,表明形成的三维网络结构阻碍了PSDAPG中芘单元的运动性, 使得以Birks途径形成激基缔合物的效率降低.     

基于二噻吩并[2,3-b:3′,2′-d]噻吩开环反应的二芘基四联噻吩的制备及其激基缔合物荧光行为

通过芘基锂对二(三甲基硅基)二噻吩并[2,3-b:3′,2′-d]噻吩开环产生碳负离子,再经氯化铜氧化偶联,获得二芘基四联噻吩化合物.考察了该化合物在溶液中的光谱行为,结果表明,该化合物在溶液相的部分分子可以发生基于分子构象折叠而形成的分子内激基缔合物;在THF-H2O二元体系中可以形成分子间的基于激基缔合物的聚集诱导发光现象.     

芘在改性硅胶上的光物理研究——以芘为探针研究改性硅胶的表面特性

研究了芘在正十碳烷氧基和三甲基硅氧基改性硅腔表面上的荧光光谱和寿命。在这二种硅胶上,激基缔合物是由基态聚积体直接受光和受激发的单分子和基态的单分子所形成、在硅胶≡Si—O—C_(10)H_(21)-n上比在硅胶≡Si—O—SiMe_3上所形成的聚积体较少。化学改性与物理改性相结合可使芘在较大的浓度范围内主要以单分子分散。激基缔合物的形成主要是由动力学过程所控制。研究了温度对芘的荧光光谱和寿命的影响。激基缔合物形成过程的活化能约为7kcal mol~(-1)。讨论了环境对单分子荧光光谱结构的影响。     

疏水作用对光化学和光物理过程的影响 Ⅶ.芘基烷基酮的荧光光谱及其在不良溶剂中的簇集

溶剂的极性对芘基烷基酮的单体荧光和激基缔合物荧光有很大影响,在非极性溶剂中单体荧光很弱,随着溶剂极性增大,单体荧光增强,单体荧光和激基缔合物荧光明显红移。利用芘基烷基酮荧光的这些性质研究了长链分子在二甲基亚砜-水(DMSO-H₂O)中的簇集现象。在浓度非常低的情况下,长链芘基烷基酮发射激基缔合物荧光,单体荧光也明显蓝移,表明芘基烷基酮形成了簇集体。长链饱和烷烃和芘基烷基酮发生共簇集,簇集体内的极性比环己烷的极性稍大。     

Exciplex and excimer molecular probes: detection of conformational flip in a myo-inositol chair

2-O-tert-Butyldimethylsilyl-4,6-bis-O-pyrenoyl-myo-inositol-1,3,5-orthoformate (6) and 2-O-tert-butyldimethylsilyl-4-O-[4-(dimethylamino)benzoyl]-6-O-pyrenoyl-myo-inositol-1,3,5-orthoacetate (10) adopt conformationally restricted unstable chairs with five axial substituents. In the symmetrical diester 6, the two pi-stacked pyrenoyl groups are electron acceptor-donor partners, giving a strong intramolecular excimer emission. In the mixed ester 10, the pyrenoyl group is the electron acceptor and the 4-(dimethylamino)benzoyl ester is the electron donor, giving a strong intramolecular exciplex emission. The conformation of the mixed ester 10 was assessed using 1H NMR spectroscopy (1H-NOESY) and computational studies. which showed the minimum inter-centroid distance between the two aromatic systems to be approximately 3.9 A. Upon addition of acid, the orthoformate/orthoacetate trigger in 6 and 10 was cleaved, which caused a switch of the conformation of the myo-inositol ring to the more stable penta-equatorial chair, leading to separation of the aromatic ester groups and loss of excimer and exciplex fluorescence, respectively. This study provides proof of principle for the development of novel fluorescent molecular probes.     

高交联苯乙烯-二乙烯苯共聚物中悬挂双键的反应及应用

本文介绍高交联大孔苯乙烯－二乙烯苯（St-DVB)共聚物中悬挂双键的存在、反应，及有关应用。已有的研究结果说明，利用悬挂双键的功能基反应是对St-DVB共聚物改性的一条重要途径。     

PREPARATION AND CELL COMPATIBILITY OF FUNCTIONALIZED BIODEGRADABLE POLY(DL-LACTIDE-CO-RS-Β-MALIC ACID)

In order to create a functionalized biodegradable polymer for vascular tissue engineering application,poly(DL- lactide-co-RS-β-malic acid)(PDLLMAc)was synthesized.PDLLMAc was obtained after hydrogenolysis of poly(DL- lactide-co-RS-β-benzyl malolactonate)(PDLLMA),which was from the ring-opening polymerization of DL-lactide(DLLA) and RS-β-benzyl malolactonate(MA)using stannous octoate as catalyst.The copolymers were characterized by ~1H-NMR, FTIR,GPC and DSC.The tensile strength and water uptake of the cop...     

Functional polymers based on acrylamide crosslinked copolymers

Crosslinked copolymers of acrylamide were obtained by the aqueous suspension polymerization method. Divinylbenzene and N,N-methylene-bis-acrylamide were used as crosslinking agents. Ethylacrylate was used as a third comonomer. The real acrylamide content in the crosslinked copolymers was calculated taking into account the found nitrogen content after the removal of the soluble fractions. The water uptake in dependence on the copolymer structure gave information on the hydrophilicity of these copolymers. Hofmann degradation of the amide groups led to copolymers containing vinylamine functional groups, which were characterized by IR spectroscopy and by anion exchange capacity. Carboxylic groups were generated by the alkaline hydrolysis of the ester groups.     

Photochromic liquid-crystalline copolymers containing crown ether groups

An approach was developed for the synthesis of new multifunctional photosensitive liquid-crystalline copolymers of the acryl series containing azobenzene, ionophoric, and mesogenic groups in the same macromolecule. The phase behavior of the copolymers was studied. Most of these copolymers were demonstrated to form nematic mesophases. An increase in the concentration of crown-containing groups to 26 mol.% leads to amorphization of the copolymers. The influence of complexation of the crown ether groups of the copolymers with potassium perchlorate on the mesomorphic properties of the systems was investigated. A comparative study of the photooptical properties of the copolymers in solution and thin films was performed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2332–2242, December, 2007.     

SYNTHESIS AND STRUCTURE OF MACROPOROUS MA-TMPTA COPOLYMERS AND THEIR APPLICATION IN ADSORPTION OF FLAVONOIDS FROM GINKGO LEAVES EXTRACT

1 INTRODUCTIONAdsorption by macroporous polymeric adsorbents is one of tile important methods inpurification of ginkgo leaves extract ill. Amberlite XAD-7, a macroporous polymeric adsorbentbased on methyl methacrylate - trimethylolpropane triacrylate copolymer, was reported to use inadsorptive purification of ginkgo leaves extract and other natural products containing flavonoidsfi.3]. Interaction between the adsorbent and flavonoids is based on hydrogen bonding between theester carbonyl-…     

PREPARATION AND CELL COMPATIBILITY OF FUNCTIONALIZED BIODEGRADABLE POLY(DL-LACTIDE-co-RS-β-MALIC ACID

In order to create a functionalized biodegradable polymer for vascular tissue engineering application,poly(DL- lactide-co-RS-β-malic acid)(PDLLMAc)was synthesized.PDLLMAc was obtained after hydrogenolysis of poly(DL- lactide-co-RS-β-benzyl malolactonate)(PDLLMA),which was from the ring-opening polymerization of DL-lactide(DLLA) and RS-β-benzyl malolactonate(MA)using stannous octoate as catalyst.The copolymers were characterized by ~1H-NMR, FTIR,GPC and DSC.The tensile strength and water uptake of the copolymers were measured.In copolymerization,the proportion of MA in the derived copolymers was lower than that in the feeding dose,a consequence of its lower reactivity. The molecular weight of the copolymers decreased with increasing MA content.The protective benzyl groups were completely removed in hydrogenolysis.The glass transition temperature(T_g)of the protected copolymers decreased with increasing MA content.The mechanical strength test showed that the tensile strength of PDLLMA decreased while elongation increased with MA content increasing,and the tensile strength increased and elongation decreased with increasing malic acid content in PDLLMAc for the formation of hydrogen bonding.The water uptake showed that more hydrophilic malic acid adsorbed more water in PDLLMAc.In order to test the reactivity of functional pendant groups,bioactive RGD peptide was immobilized on the functionalized polymer film surface and smooth muscle cells(SMCs)were cultured on it. The results showed that the functionalized copolymer was biocompatible and could be potentially applied in vascular tissue engineering.     

Synthesis and surface properties of fluorinated block copolymers containing sulfonic groups

A series of fluorinated block copolymers with different fluorinated block lengths and compositions were synthesized by atom transfer radical polymerization (ATRP), and then the block copolymers containing sulfonic groups with various sulfonation levels were successfully prepared further via a sulfonation reaction. These well‐defined block copolymers were characterized by means of Fourier transform infrared (FTIR), ¹H‐nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The surface activities of the fluorinated block copolymers containing sulfonic groups in N‐methyl pyrrolidone solution and the surface properties of the films prepared from such a solution were examined, and the experimental results showed that the fluorinated block copolymers exhibited a high surface activity in solution and quite a low solid surface energy of films, even though they contain hydrophilic sulfonic groups. The critical surface tensions of these copolymers were estimated and were comparable to that of polytetrafluoroethylene. Even more interestingly, the surface activities of the block copolymers containing sulfonic groups or sodium sulfonate groups in aqueous solution were also measured. It was found that the surface activity in aqueous solution was weaker than that in N‐methyl pyrrolidone solution and depended on both the length of the fluorinated block and the sulfonation level of the block copolymers. The surface properties of the films prepared from the block copolymers in aqueous solution were tested, and most of these films exhibited a hydrophilic surface property. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4809–4819, 2004     

三烯丙基异氰尿酸酯交联共聚物的研究(Ⅱ)——醇解物的制备、结构及其性能

将醋酸乙烯酯与三烯丙基异氰尿酸酯共聚物进行皂化制得含有羟基和羧基盐的共聚物以增强共聚物的亲水性,用作气相色谱固定相,考察了不同交联度对皂化反应的影响,测定了皂化后共聚物的孔结构参数及溶胀性能,并对该固定相的色谱性能进行评价。     

Amphiphilic block and statistical siloxane copolymers with antimicrobial activity

Statistical and block all‐siloxane copolymers containing quaternary ammonium salt (QAS) groups with biocidal activity as lateral substituents were synthesized as models for the study of the effect of the arrangement of the QAS groups in the copolymer chain on their antimicrobial activity. The bioactive siloxane unit was [3‐n‐octyldimethylammoniopropyl]methylsiloxane, and the neutral unit was dimethylsiloxane. The copolymers also contained siloxane units with unreacted precursor 3‐chloropropyl or 3‐bromopropyl groups. A small number of units containing highly hydrophilic 3‐(3‐hydroxypropyl‐dimethylammonio)propyl groups were introduced to increase the solubility of the copolymers in water. The bioactive and bioneutral units were arranged in the polymer chain either in blocks or in statistical order. The block copolymers differed in the number and length of segments. The copolymers were obtained by the quaternization of tertiary amines by chloropropyl or bromopropyl groups attached to polysiloxane chains. The arrangement of the bioactive groups was controlled by the arrangement of the halogenopropyl groups in the bioactive copolymer precursor. All model siloxane copolymers showed high bactericidal activity in a water solution toward the gram‐negative bacteria Escherichia coli and the gram‐positive bacteria Staphylococcus aureus. However, no essential differences in the activities of the copolymers with block and statistical arrangements of units were detected. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2939–2948, 2003