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1.
以1,8-萘酰亚胺为原料,合成了两种含萘酰亚胺官能团的乙烯基单体(NAPa和NAPb)。通过核磁、元素分析、紫外吸收光谱等对化合物结构进行了表征。并以这两种化合物为单体,通过原子转移自由基聚合(ATRP)的方法合成了它们均聚物,用1H-NMR ,GPC等对均聚物的结构进行了表征。研究了单体及其聚合物在不同浓度、不同溶剂以及在聚合物薄膜中的激发和发射荧光光谱,考察了聚合物浓度、溶剂极性等对荧光的影响。结果表明,单体和均聚物都具有较强的绿色荧光, 均聚物的荧光量子效率(φPNAPa=0.34, φPNAPb=0.35)高于单体的荧光量子效率(φNAPa=0.25, φNAPb=0.27)。  相似文献   

2.
铽多元配合物的合成及其性质研究   总被引:4,自引:4,他引:4  
通过铽金属醇盐与丙烯酸、β二酮配体反应,合成了4种具有聚合活性的含铽配合物单体,通过元素分析红外光谱、紫外光谱,确定了它们的组成和结构。热分析表明,这些铽配合物单体没有熔点,起始分解湿度在190-200℃之间。在溶液及状态下研究了这些含铽多元配合物的荧光性质,在紫外光激发下,它们均能发射铽离子的特征荧光,溶剂的极性和配体的三线态能级会影响它们的光强度;粉末状态下,这些铽多元络合物的荧光单色性较好。  相似文献   

3.
The syntheses of three methacrylate monomers with cinnamate ester side-chains and of a further monomer with a corresponding cinnamide side-chain are described. Two of the monomers, with isomeric structures, were thermotropic liquid crystals. Although the clearing points were very similar the crystal melting points differed by 8°C. One compound also exhibited a monotropic smectic phase, behavior not shown by its isomer. The other two monomers were not liquid crystalline. The monomers were polymerized by free radical polymerization, both as homopolymers and as copolymers with methyl methacrylate. In the case of one of the mesogenic ester monomers, copolymers with a cyanophenyl benzoate monomer were also prepared. Three of the four monomers formed thermotropic liquid crystalline homopolymers and the copolymers with the benzoate monomer were also liquid crystalline. The monomers were considered as photoactive components of polymeric liquid crystals. As a preliminary investigation of their photochemistry, copolymers with methyl methacrylate were prepared and irradiated in solution with a broad-band source. Under these conditions two of the materials show a facile photo-Fries rearrangement of the aryl cinnamate ester group. © 1992 John Wiley & Sons, Inc.  相似文献   

4.
Two nematic liquid crystal (LC) monomers containing double bonds in the side chain were designed and synthesised. Length of the side groups varied from 1 to 2 methylene units. The side-chain polymers were synthesised by hydrosilylation reaction. The molecular structures of the intermediates and the LC monomers were characterised by Fourier transform infrared, elemental analysis and nuclear magnetic resonance spectroscopy. The thermal phase behaviour of the monomers and polymers were investigated by differential scanning calorimetry and polar optical microscopy coupled with hot stage. The LC monomers showed only one nematic mesophase in the cooling process. And, the two polymers exhibit an enantiotroppic nematic mesophase either in the heating or in the cooling process.  相似文献   

5.
A series of hyperbranched aromatic polyamide copolymers has been prepared and characterized from direct polycondensation of AB2 and AB monomers. Structure of the monomers and the molar ratio of AB2/AB showed strong influence on the properties of resulting copolymers. A small amount of AB2 branching unit improved markedly the solubility of the resulting copolymer. Mark-Houwink parameters of the copolymers were essentially independent of the mole ratio of the monomers. The physical and mechanical properties of resulting copolymers were influenced not only by the mole ratio of monomers, but also by the structure of the monomers employed.  相似文献   

6.
含铽配合物的合成及其荧光性研究   总被引:1,自引:0,他引:1  
采用稀土铽金属醇盐与丙烯酸、乙酰丙酮、中性配体(邻菲啰啉或联吡啶)反应,在非水介质下合成具有高聚合活性的含铽配合物单体,通过元素分析、红外光谱、紫外光谱确定了它们的组成和结构,合成的铽配合物单体溶于一般的有机溶剂并能强烈吸收紫外光谌芤杭胺勰┳刺卵芯空庑┑ヌ宓挠庑浴T谧罴鸭し⒉ǔは拢蔷芊⑸滹胱拥奶卣饔猓ド越虾谩Q返淖刺叭芗恋募远耘浜衔锏牡ヌ宓挠庑杂薪洗笥跋欤行耘涮辶诜茊⒘拎さ囊芴岣咚堑挠夥⑸淝慷取  相似文献   

7.
The vapor-phase graft copolymerization of vinyl chloride and vinylidene chloride onto polypropylene fibers was studied by a simultaneous γ-irradiation technique. The weight increase during irradiation due to the grafting in monomers at constant vapor pressure was measured by a sensitive spring balance. The sorption of both monomers onto unirradiated polypropylene fibers was also measured. The graft copolymerization reaction was suppressed with increasing irradiation temperature, and the overall activation energies of grafting were negative in both monomers, ?2.4 kcal/mole for vinyl chloride and ?6.3 kcal/mole for vinylidene chloride. The initial rate of grafting increased linearly with the vapor pressure of monomers. The above dependence was found to parallel the sorption of monomers on polypropylene fibers. The reaction rates were proportional to the 0.9 power of the dose rate in both monomers. The relationship between the grafting and the sorption of monomers was discussed on the basis of kinetics.  相似文献   

8.
Some lipid-like monomers were synthesized by acylation of synthetic and naturally occurring amine-containing lipids with acryloyl chloride. The surfactant properties and peculiarities of polymerization of lipid-like monomers in oriented systems were investigated. On the basis of such monomers, polymeric monolayers and liposomes were prepared that have the structural similarity to biomembranes and enhanced stability. The applicability of such systems for immobilization of membrane proteins was shown for the example of bacteriorhodopsin.  相似文献   

9.
New carbazole monomers were synthesized and their cationic photopolymerization investigated. The monomers contain in each molecule two pendant carbazole groups and two functional groups reactive towards cationic photopolymerization. The investigated reactive groups were epoxy, oxetane or vinyl ether. Each type of monomer contains a spacer group namely ethylene oxide segment. The UV curing kinetics of the different monomers was monitored by real time FT-IR (RT-FTIR) analysis and the thermal properties evaluated by DSC.  相似文献   

10.
设计并合成了含偶氮苯生色团的环氧类功能单体和仅含咔唑环的单体,并以一定比例通过阳离子开环聚合合成了三个新的非共轭主链具有光折变生色团的聚合物,并用GPC、DSC、FT-IR、TG和UV-Vis等手段对所得聚合物进行了表征,考察了共聚单体配比对聚合物玻璃化转变温度的影响。UV-Vis谱图说明聚合物的最大吸收波长取决于生色团的种类。DSC结果显示,通过改变两个单体的配比可以有效调节共聚产物的玻璃化转变温度。TG结果显示,聚合物具有好的热稳定性,325℃左右开始分解。  相似文献   

11.
Abstract

A novel and facile synthesis of aromatics containing di- and tetrafunctional propenyl ether monomers is reported. These monomers were prepared by the base-catalyzed condensation of allyl glycidyl ether with a variety of bisphenols followed by allylation of the secondary hydroxyl groups and finally isomerization of the allyl groups by a ruthenium catalyst. The cationic photopolymerization of these novel monomers to give crosslinked network polymers was carried out using a diaryliodonium salt photoinitiator. The reactivity of the multifunctional propenyl ether monomers was studied using real-time infrared spectroscopy and by differential scanning photocalorimetry.  相似文献   

12.
The two title monomers were synthesized. In both cases the key cyclobutane intermediates were obtained by cycloaddition of allene to acrylonitrile or chloromaleic anhydride. These two new monomers proved to be highly reactive in free radical polymerization, and each polymerized spontaneously in air at room temperature. Linear polymers were prepared in dimethyl sulfoxide solution at 35° with AIBN and UV light. At higher temperatures crosslinking became a problem in some instances. The structure of the polymers derived from 1,4 polymerization in the diene portion of the monomers was confirmed by 13C-NMR, 1H-NMR and IR spectra. Copolymers were prepared with methyl methacrylate, styrene, and p-methoxystyrene and were always rich in the methylene-cyclobutene monomers used. Films of homopolymers and copolymers could be cast from chloroform solution.  相似文献   

13.
Phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were prepared by the regioselective addition reaction of glycidyl vinyl ether (GVE) or 1‐propenyl glycidyl ether with diaryl phosphonates with quaternary onium salts as catalysts. The reaction of GVE with bis(4‐chlorophenyl) phenylphosphonate gave bis[1‐(4‐chlorophenoxy methyl)‐2‐(vinyloxy)ethyl]phenylphosphonate in a 68% yield. The structures of the resulting phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were confirmed by IR and 1H NMR spectra and elemental analysis. Photoinitiated cationic polymerizations of the resulting phosphorus‐containing vinyl ether monomers and 1‐propenyl ether monomers were investigated with photoacid generators. The polymerization of vinyl ether groups and 1‐propenyl ether groups of the obtained monomers proceeded very smoothly with a sulfonium‐type cationic photoinitiator, bis[4‐(diphenylsulfonio)phenyl]sulfide‐bis(hexafluorophosphate), upon UV irradiation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3105–3115, 2005  相似文献   

14.
Novel mono‐ and difunctional aliphatic oxyalcohol‐based benzoxazines have been synthesized and characterized in detail. Molecular structures of the monomers were investigated by spectral analysis. The obtained benzoxazine monomers exhibit fluidic behavior, which makes them particularly useful for many applications compared to other traditional benzoxazines. Differential scanning calorimetry was used to monitor the thermal crosslinking behavior of synthesized monomers. Mono‐ and bifunctional benzoxazine monomers exhibited low curing exhothermic peak with the onset around 173 and 180 °C, respectively. Relatively, low ring‐opening polymerization temperature was due to the hydroxyl groups present in the structure of the monomers. The hydrogen bonding of hydroxyl groups may cause alignment of the monomers in the liquid state. Thermal stabilty of the polybenzoxazines was studied by thermogravimetric analysis. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2009  相似文献   

15.
Novel phenyl benzoate-based and biphenyl-based liquid crystalline thiol-ene monomers were synthesized and their properties investigated. By varying the bridging unit and spacer length, the type of mesophase can be tuned from the low ordered nematic and smectic A phase in the case of the phenyl benzoate-based monomers, to the highly ordered crystal E phase for the biphenyl-based monomers and their corresponding bromo precursors. We investigated the degree of order of the phenyl benzoate-based materials using the Haller method. Possible premature polymerization of these monomers was examined by size exclusion chromatography. The materials exhibit low transition temperatures and a high stability at typical handling times and temperatures. Consequently, these monomers are useful for in situ polymerization with anisotropic inert solvents, which could potentially lead to new architectures and enhanced electro-optical properties of devices. The use of the biphenyl-based monomers appears to be of limited use for polymerizations in anisotropic solution. However, as a result of their intrinsic high degree of molecular order, these monomers form a particularly interesting class of reactive materials that can be bulk polymerized to give main chain polymers with highly defined mechanical and optical or electro-optical properties.  相似文献   

16.
Novel phenyl benzoate-based and biphenyl-based liquid crystalline thiol-ene monomers were synthesized and their properties investigated. By varying the bridging unit and spacer length, the type of mesophase can be tuned from the low ordered nematic and smectic A phase in the case of the phenyl benzoate-based monomers, to the highly ordered crystal E phase for the biphenyl-based monomers and their corresponding bromo precursors. We investigated the degree of order of the phenyl benzoate-based materials using the Haller method. Possible premature polymerization of these monomers was examined by size exclusion chromatography. The materials exhibit low transition temperatures and a high stability at typical handling times and temperatures. Consequently, these monomers are useful for in situ polymerization with anisotropic inert solvents, which could potentially lead to new architectures and enhanced electro-optical properties of devices. The use of the biphenyl-based monomers appears to be of limited use for polymerizations in anisotropic solution. However, as a result of their intrinsic high degree of molecular order, these monomers form a particularly interesting class of reactive materials that can be bulk polymerized to give main chain polymers with highly defined mechanical and optical or electro-optical properties.  相似文献   

17.
[reaction: see text] The stabilities of various functionalized norbornenes that are monomers for the ring-opening metathesis polymerization (ROMP) in aqueous solution were evaluated toward hydrolysis under a range of temperatures (37, 60, and 80 degrees C) and pH values (3-9). All monomers contain hydrolyzable linkages to pendant functional groups, and conclusions were drawn relating to how the chemical diversity of these pendant functional groups, in accordance with the pH and temperature variations, affect hydrolysis of the aforementioned linkages. The hydrolysis was monitored by reverse phase HPLC analysis, and/or NMR spectroscopy. As expected, monomers containing ester linkages were fairly labile at higher pH values, while acetal-based linkers were cleaved at lower pH values. Beta-amino ester groups experienced a significant increase in hydrolysis rate, while carboxylic acid-containing monomers did not follow any clear trend. Saccharide-containing monomers exhibited unique behaviors for various pH values and temperature ranges.  相似文献   

18.
Novel disubstituted EDOT monomers were synthesized in good yields from 3,4-dimethoxythiophene and (chiral) glycols by transetherification. The stereochemistry of the monomers affects the electronic properties of the corresponding chiral PEDOT derivatives.  相似文献   

19.
Polymer-dispersed liquid crystal (PDLC) films were prepared by photochemical polymerisation with a series of (meth)acrylate monomers. The effects of monomer structure on the morphology of polymer networks in the PDLC films were studied. The acrylate monomers without sidegroup chain formed uniform polymer networks. The methacrylate monomers with methyl as their sidegroup chains formed lace-like networks. The size of the LC droplets increased with increasing the length of the flexible chain of both methacrylate and acrylate monomers. Meanwhile, the effects of the morphology of the polymer network on the electro-optical properties of PDLC films were also investigated.  相似文献   

20.
The polymerization in micellar and isotropic media of a head-tail pair of surfactants, i.e. of monomers bearing the methacrylate group either at the polar head or at the end of the lipophilic chain is investigated in this study. Owing to the tailor-made structure of these monomers, any differentiations observed in their polymerization can be primarily attributed to topochemical effects resulting from the different location of the polymerizable group in the two monomers. Both monomers exhibited mesomorphic-like textures, which were examined by optical microscopy and DSC studies. Also, their respective polymers showed mesomorphic behaviour, which was found to be dependent on the position of the backbone relative to the polar head.  相似文献   

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