Cationic polyelectrolytes,XII. PEG-precursor for water-soluble cationic polymers with tertiary n-atoms in the main chain

Water-soluble cationic polymers were obtained by polyaddition of poly(ethylene glycol) (PEG) diglycidylethers (M?_n of PEG were 396, 587, 1437 and 3554, resp.) with asymmetrical diamines such as N,N-dimethyl-1,3-diaminopropane and N,N-diethyl-1,3-diaminopropane. The cationic polymer properties depend on the PEG initial molecular weight and on the diamine reactivity too. PEG with M?_n = 396 had the best behaviour in these reactions. The polyelectrolyte feature of cationic polymers was emphasized both in dilute aqueous solutions and in 2M aqueous NaCl solutions. The polyelectrolyte behaviour in 2M aqueous NaCl solution is determined by the PEG chain presence.     

Introduction of quaternary amines onto a film surface by graft polymerization

Quaternary amines were introduced onto a poly(ethylene terephthalate) (PET) film surface by two different methods using UV-induced graft polymerization. The first involves a two-step reaction: graft polymerization of N,N′-(dimethylamino)ethyl methacrylate (DMAEMA) onto the PET film, followed by quaternization of the tertiary N,N′-dimethylamino groups of grafted chains using alkyl bromides (R_nBr). The second is direct graft polymerization of DMAEMA having pendant quaternary amines onto the PET film. The alkyl bromides used for quaternization of the monomers and graft chains include: n-propyl, n-butyl, n-octyl, n-lauryl, and n-cetyl bromide. The two-step method could quaternarize 90% of the pendant N,N′-dimethylamino groups of the graft chains when R₃Br was used. The extent of quaternization decreased with the increasing carbon number of alkyl bromide. The direct one-step method gave a graft amine density of 8 nmol/cm² when the monomer quaternized with R₃Br was used for the graft polymerization in the presence of 1 X 10^-3M sodium metaperiodate. The carbon number of alkyl chains in the quaternary amines estimated from XPS spectra was in good agreement with that of R_nBr used for quaternization. © 1996 John Wiley & Sons, Inc.     

Ring‐opening polymerization of epichlorohydrin and its copolymerization with other alkylene oxides by quaternary catalyst system

An effective quaternary catalyst consisting of trialkyl aluminum, phosphoric acid, electron donor, and water for ring‐opening polymerization of epichlorohydrin (ECH), as well as its copolymerization with ethylene oxide (EO), propylene oxide (PO), and allyl glycidyl ether (AGE) to obtain elastomers, were studied. We investigated the optimum composition for the quaternary catalyst; the character of the catalyst; the reactivity of the four alkylene oxides during homopolymerization and copolymerization; the behavior of ECH, EO, and PO during terpolymerization; and glass transition temperatures of the copolymer and terpolymers. The results showed that the nitrogen‐containing electron donors are suitable as the third component, whereas oxygen‐containing electron donors are not. Water as the fourth component can increase the molecular weight of the homopolymer and copolymers of ECH. According to the polymerizability of tetrahydrofuran with the quaternary catalyst and the reactivity ratios of the four alkylene oxides, the quaternary catalyst was assumed to be of a coordinated anionic type. The reactivity ratios for these four alkylene oxides were determined to be EO > PO > AGE > ECH. They were verified by terpolymerization of ECH, EO, and PO. The glass transition temperature of the terpolymer exhibits a minimum value at nearly 3:1 molar ratio of PO to EO, when the molar ratio of ECH used is constant at the beginning of terpolymerization. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2446–2454, 2001     

Polymers with acyloxime ester groups in the main chain. 2. Photochemical synthesis of block copolymers

Block copolymers of styrene and methyl methacrylate (MMA) were prepared in a two-stage free-radical polymerization by means of an azo-acyloxime ester (AOE) initiator. In the first stage, photosensitive styrene prepolymers were synthesized by using AOE initiator. These polymers were photolysed in the presence of MMA in the second stage to form block copolymers. The block copolymer structure was elucidated by means of extraction by appropriate solvents, GPC analysis and IR and NMR spectral measurements.     

Polymers with mesogenic elements in the main chain: A nematic aromatic copolyester

Properties of a copolyester based on methylhydroquinone, pyrocatechol and terephthalic acid have been described. Light scattering data for the copolyester in chloroform and dichloroacetic acid are well represented by $\text{M}\text{?}{}_{\mathrm{w}}\text{=220 000}$ while the intrinsic viscosity is 0.22 dl g^?1, which implies a compact arrangement of the molecule in dilute solution. Differential scanning calorimetry (d.s.c.) traces show that the copolyester is essentially non-crystalline in character. Polarizing microscopy (texture observations, miscibility tests) provides definite proof as to the nematic structure of the melt. Well aligned samples can be produced either by subjecting nematic melt to a magnetic field (H_c = 0.6 T) or by suitable treatments of the slides between which the melt is observed. The conoscopic interference pattern corresponds to that of a uniaxial system showing an optically positive character. A structural model is proposed to account for the X-ray patterns obtained from oriented samples.     

Polymers with mesogenic elements and flexible spacers in the main chain: Aromatic-aliphatic polyesters

A new series of aromatic-aliphatic polyesters of general structure: R₁ = terphenyl, biphenyl, stilbene R₂ = (CH₂)_n; ? CH₂? C(Me)₂? CH₂? ;? CH₂;? C(Et)₂? CH₂? ; (CH₂? CH₂? O)_n CH₂? CH₂? has been synthesised. The existence of thermotrpic liquid crystalline phases has been shown by polarised light microscopy. The texture observations have suggested the existence of nematic, S_A or/and S_C phases depending on the chemical structure. The temperature of transition between the phases and, as a consequence, the range of mesomorphism are highly dependent upon the chemical structure. The clearing point is high, even for the longest aliphatic group, while the melting point is depressed.     

沉淀聚合法制备丙烯酰胺类聚电解质研究进展

论述了沉淀聚合法制备丙烯酰胺类聚电解质的研究现状,从极性溶剂、疏水缔合、电解质作用、聚合反应几方面探讨了对丙烯酰胺类聚电解质溶解性能的影响因素。由水、极性溶剂、分散剂、无机盐组合溶剂,总结了各种溶剂体系对沉淀聚合反应的影响,提出了需要进一步解决的问题。     

Photoactive epichlorohydrin, 2. Photoinitiated free-radical and promoted cationic polymerization by using polyepichlorohydrin with benzoin terminal groups

The photoinitiated free-radical polymerization of methyl methacrylate (MMA) and the radical-promoted cationic polymerization of cyclohexene oxide (CHO) in the presence of low-molecular-weight polyepichlorohydrin terminated with groups containing benzoin derivatives were studied. Benzoin-terminated polyepichlorohydrin was prepared by Activated Monomer (AM) polymerization. Upon photolysis. polymer-bound alkoxy benzyl radicals were generated, initiating the radical polymerization of MMA. In the case of radical-promoted cationic polymerization of CHO, the cationic initiating species were formed by the oxidation of photochemically generated polymeric radicals by N-ethoxy-2-methylpyridinium hexafluorophosphate.     

Synthesis of polymers having 1,3-cyclobutanedione unit in the main chain by cycloaddition polymerization of bisketene

Summary A novel polymer having 1,3-cyclobutanedione unit in the main chain was prepared by cycloaddition polymerization of the bisketene derived from 1,4-cyclohexanedicarbonyl chloride. The polymer was soluble in MeOH, acetone, and CHCl₃. The structure of the polymer was confirmed by IR, ¹H-, and ¹³C-NMR spectroscopies compared with those of the model compounds. The polymer was found to contain anhydride bond as well as 1,3-cyclobutanedione unit in the main chain. The anhydride bond in the polymer was cleaved by MeOH under reflux condition in benzene. Received: 8 February 1999/Accepted: 16 March 1999     

Thioetherglycidyl resins. IV. Products of condensation of isomeric di(mercaptomethyl)xylene with epichlorohydrin

Thioetherglycidyl resins produced by condensation of isomeric di(mercaptomethyl)xylene with epichlorohydrin were obtained by heterophase alkaline condensation in water and isopropyl alcohol solution using sodium hydroxide. The structure of thioetherglycidyl resins was determined by elemental analysis, infrared, and NMR spectra, and their physical and chemical properties were defined. Some properties of the resins, cured chemically or thermally with typical for epoxy resins, and thermal and mechanical properties of the cured compounds were determined.     

Synthesis and characterization of electroactive polyamide with amine-capped aniline pentamer and ferrocene in the main chain by oxidative coupling polymerization

A novel electroactive polymer, polyamide with well-defined oligoaniline and ferrocene in the main chain, has been successfully synthesized through a novel oxidative coupling polymerization. The polymerization characteristics and structure of the copolymer were systematically studied by gel permeation chromatographic (GPC), Fourier-transform infrared (FTIR) spectra, ¹H NMR and X-ray powder diffraction (XRD). And its spectroscopic properties and electrochemical behavior were studied by UV-vis spectra and cyclic voltammetry (CV). It was found that the obtained polyamide bearing amine-capped aniline pentamer and ferrocene segments had a reversible electrochemical property in the cyclic voltammetry, but showed four distinct oxidation states, which is different from polyaniline. Moreover, its electrical conductivity is about 7.6×10⁻⁷ S cm⁻¹ at room temperature upon preliminarily protonic-doped experiment.     

Hydrophilic PVC composite films obtained by in situ polymerization, 1. Swelling studies

In order to introduce a monomer into a PVC matrix, the swelling behavior of PVC films was tested in four solvents (acetone, methyl ethyl ketone, benzene, and toluene) and in acrylic acid solutions in acetone (10, 25 and 50 wt.-%) containing 0.1 wt.-% azoisobutyronitrile. The type of transport, diffusion and permeation coefficients, sorption kinetics and Arrhenius parameters are discussed.     

Coordinate polymerization of heterocycles: 1. Oligomerization of epichlorohydrin by TiCl4

The polymerization of epichlorohydrin proceeds via the TiCl₄. 2EPC complex provided the concentration of epichlorohydrin is twice as high as that of TiCl₄. The oligomerization process requires supposedly the existence of a complex in which the epichlorohydrin is coordinate through a ClTi bond. Diethyl ether has an inhibiting effect on the reaction. The oligomerization rate is increased in the presence of acetyl chloride, diethyl ether having no effect this time. The transformation of epichlorohydrin to polymer is always kinetically non-stationary, the number of active centres decreasing with time. Both the initiation and propagation steps proceed through a rearrangement following the coordination of monomer to the activating ligands. No polymerization active free ions have been found to be present in the system. The intermediate and final products were analysed employing spectral, chromatographic, kinetic, and conductivity measurements. The reaction mechanism of oligomerization has been suggested.     

酸和胺直接缩合制备酰胺的进展

酰胺键的合成是有机化学中非常重要和有意义的反应之一。国内外学者已对酰胺键的形成进行了长期研究,目前合成酰胺的底物和方法多种多样,然而,这些合成方法存在各种各样的资源浪费和环境污染问题。羧酸和胺之间的催化脱水缩合反应是合成相应酰胺的最理想方法,利用羧酸和胺在催化剂作用下直接缩合形成酰胺,避免了使用活化试剂带来的诸多问题。近年来以硼类和过渡金属为主体的催化剂得到广泛研究,并取得了一系列成果。本文主要介绍了以羧酸和胺为底物,同时符合绿色化学理念的催化合成方法,通过对这些催化剂催化性能的总结与分析,阐述了各种催化剂的优缺点。其中硼化合物催化的直接酰胺化反应是研究较多、前景最为诱人的方法,因此基于硼类化合物的特殊结构,设计更具活性的此类催化剂将是今后研究发展的方向。     

Synthesis and characterization of poly(arylene ether sulfone)s with pendant amines on the main chain

Summary Synthesis of poly(arylene ether sulfone)s with random incorporation of pendant aryl amines was achieved by copolymerization of dichlorodiphenylsulfone (DCDPS) and bisphenol-A with bis(4-fluorophenyl)-3-aminophenylphosphine oxide (amino DFTPPO) with N-methylpyrrolidone (NMP) as the solvent, toluene as the azeotrope and potassium carbonate (K₂CO₃) as the weak base. A unique feature of this polymerization is that one of the comonomer (amino DFTPPO) contains both an amine functionality as well as activated dihalides which can undergo aromatic nucleophilic displacement by the phenolate, the degree of amination on the main chain can be controlled very precisely by regulating the amount of the amino DFTPPO monomer relative to the other activated dihalide monomer (DCDPS) and bisphenol-A. The synthesis and characterization of poly(arylene ether sulfone)s with various concentration of amine groups on the backbone will be discussed in this paper.     

New polyelectrolytes by ring-opening metathesis polymerization of norbornene derivatives with imidazolium functionalized oligo-alkylether pendant groups

Novel monomers are reported that are derived from norbornene functionalized with oligoethyleneoxy groups that carry imidazolium salts. These monomers were polymerized via ruthenium-catalyzed ring-opening metathesis polymerization in a variety of solvents, including ionic liquids, at different temperatures to give novel low T_g polymers. These polymers are expected to act as new polymer electrolytes.     

Polyester films obtained by noncatalyzed melt‐condensation polymerization of aleuritic (9,10,16‐trihydroxyhexadecanoic) acid in air

To mimic nontoxic and fully biodegradable biopolymers like the plant cutin, polyester films from a natural occurring fatty polyhydroxyacid like aleuritic (9,10,16‐trihydroxyhexadecanoic) acid have been prepared by noncatalyzed melt‐polycondensation at moderate temperature (150°C) directly in air. The course of the reaction has been followed by infrared spectroscopy, ¹³C magic angle spinning nuclear magnetic resonance spectroscopy, differential scanning calorimetry and X‐ray diffraction and well differentiated stages are observed. First, a high conversion esterification reaction leads to an amorphous rubbery, infusible, and insoluble material whose structure is made out of ester linkages mostly involving primary hydroxyls and partially branched by minor esterification with secondary ones. Following the esterification stage, the cleavage of vicinal secondary hydroxyls and further oxidation to carboxylic acid is observed at the near surface region of films. New carboxylic groups created also undergo esterification and generate cross‐linking points within the polymer structure. Additionally, and despite the harsh preparation conditions used, very little additional side reaction like peroxidation and dehydration are observed. Results demonstrate the feasibility of polyester films fabrication from a reference fatty polyhydroxyacid like aleuritic acid by noncatalyzed melt‐polycondensation directly in air. The methodology can potentially be extended to similar natural occurring hydroxyacids to obtain films and coatings to be used, for instance, as nontoxic and biodegradable food packaging material. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41328.     

Activation of the anionic polymerization of styrene by crown tertiary amines in cyclohexane

Summary The half life time of active species propagating the anionic polymerization of styrene in the presence of tetramethyltetraazacyclotetradecane (TMTCT), is higher than the polymerization time at room temperature. The kinetic study of the propagation step measures the activating effect for a ratio at room temperature. First-order kinetics with respect to living centres is observed; the corresponding absolute rate constant is equal to 750 1. mole^–1.s^–1 at 20°C. Such an increase of the reactivity of ion-pairs is interpreted in terms of the stretching of the carbonmetal bond in polystyryllithium.     

Vinyl polymerization by metal complexes. V. Effects of amines on the polymerization by copper(II) chelate and carbon tetrachloride initiating system

The polymerization of acrylonitrile was studied by the system of copper(II)-oligo(n)ethylene-(n+1)amine complex and carbon tetrachloride. Addition of amines to the initiating system accelerates the polymerization. The acceleration by these amines was found to be in the following order: prim.-amine<sec.-amine<tert.-amine<diamine<phenylenediamine. Effects of the sort of the ligands in the copper(II) chelates on the polymerization were also studied.