Towards hybrid carbazole/pyrrole-based carboxylated monomers: chemical synthesis, characterisation and electro-oxidation properties

Six novel hybrid carbazole (Cbz)-pyrrole (Pyr)-based carboxylated monomers were synthesised and unambiguously characterised using common spectroscopic tools. Clauson-Kaas, amide coupling, LAH (lithium aluminium hydride)-mediated reduction, esterification and debenzylation reactions were used as key chemical reactions towards their multi-step synthesis. The electro-oxidation features of all these six hybrid Cbz/Pyr-monomers were investigated for the electro-deposition of corresponding polyCOOH conducting coatings. Quite interestingly, and due to the fact that such electro-oxidisable monomers contain both types of oxidisable heterocycles, that is, Pyr and Cbz species, it was found that the successful electro-polymerisation of these hybrid Cbz/Pyr-monomers was highly dependent on the relative number of Cbz versus Pyr unit(s) present in corresponding monomers. Indeed, a successful electro-deposition of the corresponding conducting polymeric films onto a working Pt electrode was observed only for hybrid monomers characterised by a Cbz/Pyr unit(s) ratio greater than or equal to 1. This result has been validated by systematically tuning the number of oxidisable Cbz and Pyr unit(s) present in monomers through proper chemical design and monomer multi-step synthesis. In that case, cyclic voltammogram analyses readily confirmed the exclusive electro-deposition of conductingpolyCbz-films.     

Novel carboxylated pyrrole- and carbazole-based monomers. Synthesis and electro-oxidation features

Carboxylated pyrrole (Pyr, a index)- and carbazole (Cbz, b index)-containing monomers 6-7a/b and 9a/b have been readily synthesized from the monobenzyl ester of L-glutamic acid and triamine 2 using Clauson-Kaas and amide coupling reactions. In contrast to Pyr-containing compounds 6-7a, and 9a, the three Cbz-containing monomers 6-7b, and 9b have been found electroactive and were successfully electropolymerized on a Pt electrode resulting in the deposition of corresponding insoluble electroconducting polyCOOH polyCbz-films poly(6-7b) and poly(9b).     

Synthesis and cationic photocuring of new carbazole monomers

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.     

Synthesis of polymeric 1‐iminopyridinium ylides as photoreactive polymers

Two synthetic routes to polymeric 1‐imino pyridinium ylides as new photoreactive polymeric architectures were investigated. In the first approach, polymerization of newly synthesized 1‐imino pyridinium ylide containing monomers yielding their polymeric analogues was achieved by free radical polymerization. Alternatively, reactive precursor polymers were synthesized and converted into the respective 1‐imino pyridinium ylide polymers by polymer analogous reactions on reactive precursor polymers. Quantitative conversion of the reactive groups was achieved with pentafluorophenyl ester containing polymers and newly synthesized photoreactive amines as well as by the reaction of poly(4‐vinylbenzoyl azide) with a photoreactive alcohol. The polymers obtained by both routes were examined regarding their photoreaction products and kinetics in solution as well as in thin polymer films. Contact angle measurements of water on the polymer films before and after irradiation showed dramatic changes in the hydrophilicity of the polymers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 832–844, 2010     

Synthesis of Styrene Monomers Hydroxyl Functionalized

Bifunctional monomers provide the possibility of preparing new polymeric and nano structures such as random or graft copolymers. These materials can potentially be used as surfactants or coupling agents in polymeric blends, especially where each functionality in the monomer has different chemical properties. This article describes the organic synthesis of bifunctional monomers derived from styrene through the Grignard reaction with aldehydes and ketones. The Grignard reagent was synthesized from 4-bromostyrene and magnesium in THF. At the end of the synthesis four different bifunctional monomers were obtained bearing two terminal substituents: a vinyl and a hydroxyl group. These monomers were obtained in high yield and purity. The reactivities of the monomers were probed via the random copolymerization of one of these monomers with styrene and acrylonitrile.     

Intense Near- and Mid-infrared Absorbing Films of Electrochemically Crosslinked Multinuclear Metallodithiolene Complex Polymers

Novel multinuclear metallodithiolene complexes [(Cbz)₂-BTT-Pd(dppf)]₂Ni[6b, Cbz=carbazole, BTT=benzene-1,2,4,5-tetrathiotate, dppf=1,1'-bis(diphenylphosphino) ferrocene] and polymer [(Cbz)₂-BTT-Ni]_n·[(Et)3(PhCH2)N]_x(7b) with the carbazole pendent groups were synthesized and characterized. The thin films of crosslinked polymers P6b and P7b were prepared by electrochemical polymerization of compounds 6b and 7b, respectively. These films show intense and broad absorption in the near- and mid-infrared spectral regions(P6b: 1000-1600 nm, λ_max=1297 nm; P7b: 800 nm-8 μm, λ_max=3.9 μm) and are potentially useful as infrared optical materials.     

Synthesis and characterization of new highly permeable polyamideimides from dianhydride monomers containing amide functions: An application to the purification of a fuel octane enhancer (ETBE) by pervaporation

Six polyamideimides (PAI) were synthesized from six dianhydride monomers containing amide functions. The dianhydride monomers were obtained from the reaction of trimellitic anhydride chloride with six aromatic diamines—1,4‐phenylenediamine, 2,2‐bis(4‐aminophenyl) propane, 4,4′‐oxydianiline, 4,4′‐methylenedianiline, 1,1‐bis(4‐aminophenyl)cyclohexane, and bis(4‐aminophenyl)sulfone—by a low‐temperature condensation with yields ranging from 35 to 98% depending on the monomer solubility in organic media. The monomers were characterized by Fourier transform infrared (FTIR) and ¹H NMR. In accordance with a synthesis scheme implying the reaction of a macrodiisocyanate with dianhydride monomers containing amide functions, six PAIs with a highly flexible soft block (polytetramethylene glycol PTMG 650) were synthesized with inherent viscosities ranging from 0.38 to 1.3 dL/g. Their characterization by FTIR and ¹H NMR fully confirmed their chemical structure. The strong physical crosslinking provided by polar hard blocks containing up to eight aromatic rings enabled the casting of PAI films that were very tough in the dry state and could withstand exposure to rather strong solvating media (e.g., ethers, alcohols, and chlorinated solvents). First experiments showed these materials could be good candidates for membrane‐separation applications. They revealed interesting features for the separation of organic aprotic–protic mixtures as shown by the first results obtained for the purification of a fuel octane enhancer (ethyl‐tert‐butyl ether) used in the European Community. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 614–630, 2000     

全息用光致聚合物中双单体组分对材料性能的影响

本文研究了薄膜型光致聚合物材料中双单体(2-苯氧基乙基丙烯酸酯和N-乙烯基咔唑)的不同配比对材料聚合效率的影响.用红外光谱测定了双组分单体在固体薄膜中光反应条件下的竟聚率,分析了双组分单体在全息记录过程中的聚合情况.针对同一点多角度复用的大容量存储要求,提出了双单体薄膜型光致聚合物的理想模型.初步测定了不同摩尔配比条件下材料的全息存储性能,分析了其中的影响因素.     

Melt-polymerizable bisimido-bisphthalonitriles containing silicon,fluoro, and ether groups: Synthesis,characterization, and NMR study

Various melt-polymerizable bisimido-bisphthalonitrile polymer precursors were synthesized by the reaction of 4-aminophthalonitrile (4-APN) with bis(3,4-dicarboxyphenyl) dimethylsilane dianhydride (SIDA), 4,4′-hexafluoroisopropylidene diphthalic anhydride (6FDA), bis(3,4-dicarboxyphenyl)ether dianhydride (ODPA), and 3,3′, 4,4′-tetracarboxylichenzophen+ne dianhydride (BTDA) in an aprotic solvent. The synthesized monomers showed crystalline melting at 269 and 271°C. Elemental analysis, differential thermal analysis (DTA), infrared (IR), nuclear magnetic resonance (¹H-NMR) and mass spectral studies were carried out to characterize the synthesized monomers. Thermogravimetric analysis (TGA) of the synthesized monomers showed their thermal stability at 410–400°C. A detailed study and NMR investigation of the first step of condensation reaction was carried out and indicated the formation of a transient charge transfer complex. Thermal cyclization of the formed intermediate, however, gave the required monomers. A preliminary study demonstrated that melt-polymerization of the synthesized monomers gave thermallystable, tough polymers.     

四氢呋喃正离子聚合转为烯类单体负离子嵌段共聚合的研究

本文以癸二酰氯-高氯酸银催化剂在低温引发四氢呋喃正离子聚合,用伯胺终止,制得带有双端仲胺基的聚四氢呋喃遥爪聚合物(PTHF-NHR,R为苄基、正丁基、苯基)。当R为苯基时,PTHF-NHR与萘钠的金属化反应接近完全。以PTHF-NHR的胺钠盐引发烯类单体(甲基丙烯酸甲酯、苯乙烯、丙烯腈)负离子嵌段共聚合。当R为苯基、单体为甲基丙烯酸甲酯时,室温反应可得到转化率为100％的ABA型嵌段共聚物,为热塑性弹性体,其抗张强度为157kg/cm~2,扯断伸长率为700％。     

Synthesis,characterization, and photocuring of siloxane‐oxirane monomers

The aim of this study was to synthesize, characterize, and evaluate alternative monomers for use in dentistry. Three siloxane‐oxirane low‐shrinkage monomers were synthesized, and the products’ conversion was followed by Fourier transform ‐ infrared spectroscopy. The products obtained were characterized by ¹H and ¹³C NMR and evaluated for viscosity and a refractive index. The polymerization was evaluated by formulating two experimental photoinitiation systems, which varied for the presence of 1,2 ethanediol. A ternary system with camphorquinone (CQ), ethyl 4‐dimethylaminobenzoate (EDAB), and diphenyliodonium hexafluorphosphate (DPI) was used as control. The degree of conversion was assessed by differential scanning calorimetry (DSC). The NMR confirmed the synthesis success with 75, 87, and 55% yields for the monomers synthesized. The viscosity and the refractive index of the monomers showed favorable rheological and physical behaviors for application in dentistry. Moreover, the presence of 1,2 ‐ ethanediol increased the degree of conversion of the siloxane‐oxirane monomers. This study showed a simple and effective way to synthesize siloxane‐oxirane monomers with a high potential for application in dental materials. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1728–1733     

Thermal stability and high glass transition temperature of 4-chloromethyl styrene polymers bearing carbazolyl moieties

A new styrene derivative monomer, 4-(N-carbazolyl)methyl styrene (CzMS), was synthesized by reacting 4-chloromethyl styrene with carbazole in the presence of sodium hydride. Then, CzMS was homopolymerized and copolymerized with different monomers such as methyl methacrylate (MMA), ethyl methacrylate (EMA), methyl acrylate (MA), ethyl acrylate (EA) and n-butyl acrylate (BA) by free radical polymerization method in N,N-di-methylformamide (DMF) solution at 70 ± 1 °C using azobisisobutyronitrile initiator to give the copolymers I-V in good yields. The structure of all the resulted polymers was characterized and confirmed by FT-IR, ¹H NMR and ¹³C NMR spectroscopic techniques. The average molecular weight and glass transition temperature of polymers were determined using gel permeation chromatograph (GPC) and differential scanning calorimeter (DSC) instruments, respectively. It was found that these polymers with carbazole moieties have high thermal stability and the presence of bulk carbazole groups in polymer side chains leads to an increase in the rigidity and glass transition temperature of polymers.     

Novel Peroxide Containing Maleinate Surface-Active Monomers for Obtaining Reactive Polymers

Novel surface-active monomers were synthesized by successive treatment of tert-butylperoxy-6-hydroxyhexanoate with maleic anhydride, 1,3-propane sultone and triethylamine or with maleic anhydride and poly(ethylene glycol) methyl ether. The surface-active properties of monomers were studied. The critical micelle concentrations (cmc) as well as the surface tension at the cmc were determined for obtained monomers. The synthesized compounds were shown to be suitable reactive surfactants for obtaining styrene latexes.     

Polycarbazoles via C?N coupling reactions of phthaloyl bis‐9H‐carbazoles with activated difluorides

1,3‐Phthaloyl bis‐9H‐carbazole (MPC) and 1,4‐phthaloyl bis‐9H‐carbazole (PPC) were synthesized by a Friedel‐Crafts reaction of carbazole with terephthaloyl chloride or isophthaloyl chloride. Homopolymers were obtained by a C? N coupling reaction with activated difluorides and copolymers were synthesized with 4,4′‐biphenol as a comonomer by a nucleophilic substitution reaction between these NH‐ and OH‐containing monomers and the activated difluoro monomers. The inherent viscosities of the polymers ranged from 0.35 to 1.03 dL/g. These polymers exhibited glass‐transition temperatures greater than 238 °C with the PPC‐containing homopolymer showing the highest value, 326.4 °C. The thermal stabilities indicated no significant weight loss below 450 °C and the temperatures of 5% weight loss ranged from 514.0 to 546.3 °C. The polymers showed reasonable solubility in organic solvents such as DMAC, DMSO, and NMP. UV absorption and fluorescence emission properties are presented. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4326–4331, 2009     

Design, synthesis and photo-cross-linking of a new photosensitive macromonomer from tetra-branched poly(ethylene oxide)s

A general procedure to increase the amount of photoreactive chromophore groups per oligoether chain is presented. In this work, a photoreactive macromonomer with four functionalities was synthesized by a four-step synthetic pathway with high yield. The photochemical behavior of this compound was studied with a view to obtaining polymeric networks. The significant advantage in this strategy is that the preparation of this material has as last operation, the obtaining and processing of polymer as thin film. In this way, the synthetic strategy based on assembling: (i) the polyether chains, (ii) a film forming backbone, and (iii) a photoactive moiety to be used for cross-linking, seems a viable solution to the problem of the continuous processing of materials.     

Thermally and oxidatively stable thermosets derived from preceramic monomers

Monomers 1,3-bis(4-phenylethynylphenyl)tetramethyldisiloxane and 1,7-bis(4-phenylethynylphenyltetramethyldisiloxyl)-m-carborane were synthesized and compared with bis(4-phenylethynylphenyl)dimethylsilane as potential preceramic precursors. These monomers were heated to free flowing liquids above 100°C and thermally polymerized above 300°C to form heat-resistant thermosets or ceramic residues. The ceramic yields for the silane (13%) and siloxane (30%) were much lower than that for the carborane (64%) monomer. The thermoset and ceramic made from the carborane monomer were the best thermally and oxidatively stable materials. After curing, the thermoset had a weight loss of only 6% and after pyrolysis, the ceramic residue had no additional weight loss up to 1000°C in air. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1033–1038, 1997     

含偶氮咔唑生色团氧化乙烯功能单体的合成及其聚合反应研究

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。     

Synthesis of phosphorus‐containing vinyl ether monomers and oligomers and their photoinitiated polymerization

Divinyl ether monomers containing phosphorous residues were synthesized by the addition reaction of glycidyl vinyl ether (GVE) with various phosphonic dichlorides or dichlorophosphates with quaternary onium salts as catalysts. The reaction of GVE with phenylphosphonic dichloride gave bis[1‐(chloromethyl)‐2‐(vinyloxy)ethyl]phenylphosphonate ( 1a ) in a 77% yield. The polycondensation of 1a with terephthalic acid was also carried out with 1,8‐diazabicyclo[5.4.0]undecene‐7 (DBU) as a condensing agent to afford the corresponding phosphorus‐containing polyester. A multifunctional monomer containing both vinyl ether groups and methacrylate groups was prepared by the reaction of 1a with methacrylic acid with DBU. The photoinitiated cationic polymerization of these vinyl ether compounds proceeded rapidly with bis[4‐(diphenylsulfonio)phenyl]sulfide‐bishexafluorophosphate as the cationic photoinitiator without a solvent upon ultraviolet irradiation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2031–2042, 2004     

Photochemical patterning of a self-assembled monolayer of 7-diazomethylcarbonyl-2,4,9-trithiaadmantane on gold films via Wolff rearrangement

Photolithographic attachment of functional organic molecules via ester or amide linkages to self-assembled monolayers (SAMs) on gold thin films was achieved by employing a novel photoreactive surface anchor, 7-diazomethylcarbonyl-2,4,9-trithiaadmantane. The photoreactive SAM was prepared by the spontaneous physical adsorption of the photoreactive surface anchor onto gold surfaces. The alpha-diazo ketone moiety of the SAM was found to display the classical Wolff rearrangement reactivity to produce a ketene intermediate on the exposed area. Organic molecules such as alcohols and amines can thus be attached to the gold surfaces selectively by the facile in situ formation of ester or amide linkages. The structure and reactivity of the photoreactive surface anchor were characterized by real-time FT-IR, fluorescence, and polarization modulation infrared reflectance absorption spectroscopy (PM-IRRAS). The Wolff rearrangement reactivity of the SAM suggested that a "surface-isolated" carbonylcarbene may be generated when the SAM was exposed to 255-nm irradiation.     

烷基步长对聚丙烯酸修饰咔唑电聚合的影响

合成了含有不同烷基链取代的N-丙烯酰氧癸基咔唑(MACZ10)和N-丙烯酰氧十二烷基咔唑(MACZ12), 通过自由基聚合得到聚N-丙烯酰氧烷基咔唑(PMACZ). 分子量分析表明, 随着烷基链长度的增加, 聚合物分子量减小, 分布变宽. 荧光光谱表明, 随着烷基链长度的增加, 聚合物在353 nm处的发射峰逐渐减弱. 在四氢呋喃和体积分数为10%三氟化硼乙醚与四氟化硼四丁基胺的混合电解质溶液中, 直接阳极氧化PMACZ获得自支撑交联网状的聚(聚N-丙烯酰氧烷基咔唑)(PPMACZ)薄膜. PPMACZ薄膜具有良好的氧化还原活性、热稳定性和蓝色发光性能, 聚合物氧化还原可逆性随着烷基链长的增加而增加, 且发射峰变宽.