Synthesis of Graft Polymers by Copolymerization of Macromonomers. II. Copolymerization Kinetics of Styrene-and Methacrylate-Terminatedpoly(2-Acetoxyethyl Methacrylate) Macromonomers

Styrene-terminated poly(2-acetoxyethyl methacrylate) macromonomer (EBA), methacrylate-terminated poly(2-acetoxyethyl methacrylate) macromonomer (MPA), and methacrylate-terminated poly(methyl methacrylate) macromonomer (MPM) were synthesized and subjected to polymerization and copolymerization by a free-radical polymerization initiator (AIBN). EBA and MPA were homopolymerized at various concentrations. EBA exhibited higher reactivity than styrene. The reactivity of MPA, however, was almost equal to that of glycidyl methacrylate. Cumulative copolymer compositions were determined by GPC analysis of copolymerization products. The reactivity ratios estimated were r_a = 0.95 and r_b , = 0.90 for EBA macromonomer (a)-methyl methacrylate (b) copolymerization. These values were not consistent with literature values for the styrene-methyl methacrylate and p-methoxy-styrene-methyl methacrylate systems. The reactivity ratios estimated for MPA and 2-bromoethyl methacrylate were r_a - 0.95 and r_b , = 0.98; equal to the glycidyl methacrylate-2-bromoethyl methacrylate system. MPA or MPM was also copolymerized with styrene, and the reactivity ratios were r_a = 0.40, r_a = 0.60 and r_a = 0.39, r_a = 0.58, respectively. These estimates were in good agreement with the reactivity ratios for glycidyl methacrylate and styrene. Thus, no effect of molecular weight was observed for both copolymerization systems.     

Synthesis and copolymerization of new methacrylic monomers for the creation of nonlinear optical polymer materials

A new methacrylic monomer, 3,5-bis[2-(N-ethylanilino)ethoxy]benzyl methacrylate (MBA), has been synthesized. Methacrylic copolymers with different content of bi-chromophore fragments in the side chain were obtained by radical copolymerization of methyl methacrylate and MBA, followed by azo-functionalization reaction. The composition of the obtained copolymers was established, and their thermal properties were determined. Thin films of synthesized copolymers were prepared by spin-coating and the nonlinear optical characteristics of the obtained materials were investigated.

     

Synthesis,Characterization, and Reactivity Ratios of Phenyl Methacrylate-N-vinyl-2-pyrrolidone Copolymers

Free radical solution copolymerization of phenyl methacrylate and N-vinyl-2-pyrrolidone was carried out using benzoyl peroxide in 2-butanone solution at 70°C. The composition of the copolymer was determined using ¹H-NMR spectra by comparing the intensities of aromatic protons to that of total protons. The results were used to calculaie the copolymerization reactivity ratios by both the Fineman-Ross (F-R) and Kelen-Tüdös (K-T) methods. The reactivity ratios are r ₁ = 4.49 ± 1.27 and r ₂ = 0.05 ± 0.09 as determined by the K-T method. These values are in good agreement with those determined by the F-R method. The FT-infrared and ¹³C-NMR spectra of the copolymer are discussed.     

Copolymerization of <Emphasis Type="Italic">p</Emphasis>-(2,2-dichlorocyclopropyl)styrene with Methyl methacrylate and properties of the resulting copolymers

A copolymer based on p-(2,2-dichlorocyclopropyl)styrene and methyl methacrylate was prepared by radical copolymerization. The copolymerization constants were determined, and the parameters of the Q-e scheme were calculated.     

Copolymerization of 2-hydroxypropyl methacrylate with alkyl acrylate monomers

2-Hydroxypropyl methacrylate has been copolymerized with methyl acrylate, ethyl acrylate, n-butyl acrylate, and methyl methacrylate in bulk at 60°C using benzoyl peroxide as initiator. The compositions of copolymers have been determined by the estimation of the hydroxyl group by acetylation process. The copolymerization parameters have been determined by conventional scheme of copolymerization.     

3-Tetrahydrofurfuryloxy-2-Hydroxypropyl Methacrylate: Synthesis,Characterization, Homopolymerization,and Copolymerization

Abstract

3-Tetrahydrofurfuryloxy-2-hydroxypropyl methacrylate monomer was prepared from methacrylic acid, tetrahydrofurfuryl alchol, and epichlorhydrin. Homopolymerization and copolymerization with (2-phenyl-1,3-dioxolane-4-yl)methyl methacrylate and N-vinyl pyrrolidone monomers were carried out in 1,4-dioxane solution at 60°C using benzoyl peroxide as initiator. Infrared, proton and carbon-13 nuclear magnetic resonance techniques were used in characterizations of the monomer, the homopolymer and the copolymers were determined by DSC technique. The copolymer compositions were estimated from 1H-NMR spectra. The reactivity ratios in copolymerization of 3-tetrahydrofurfuryloxy-2-hydroxypropyl methacrylate and (2-phenyl-1,3-dioxolane-4-yl) methyl methacrylate were calculated by both Kelen-Tüdos and Fineman-Ross methods.     

甲基丙烯酸三丁基锡酯与丙烯酸酯的共聚合

采用自由基引发剂对甲基丙烯酸三丁基锡酯和丙烯酸酯进行共聚合 ,其竞聚率用YBR法解出共聚方程的微分式而求得。甲基丙烯酸三丁基锡酯 (M1 )和丙烯酸甲酯 (M2 )、丙烯酸乙酯 (M2 )、丙烯酸丁酯 (M2 )共聚反应的竞聚率分别为r1 =1 .0 1± 0 .0 6,　r2 =0 .2 9± 0 .0 3;　r1 =1 .0 7± 0 .0 5 ,r2 =0 .38± 0 .0 3;　r1 =1 .1 1± 0 .0 5 ,　r2 =0 .45± 0 .0 3;　而所得到的甲基丙烯酸三丁基锡酯的Q、e值是它对各个单体的所有Q、e值的平均值 ,其Q =0 .5 7,e=- 0 .39     

Copolymerization of N-Vinylsuccinimide with Butyl Methacrylate in Pyridine

The kinetics of radical copolymerization of N-vinylsuccinimide with n-butyl methacrylate in pyridine was studied, and the previously unknown copolymerization constants of the monomers were determined. The calculations were performed using appropriate software and a new procedure for approximation of the experimental data, which allow determination of the kinetic parameters at high conversions with the minimum error. The copolymerization kinetics were compared for the reaction systems constituted by N-vinylsuccinimide and n-butyl methacrylate and by N-vinylsuccinimide and n-butyl acrylate.     

1H-NMR study of structure and tacticity in p-t-butylstyrene/methyl methacrylate copolymers

Copolymers prepared by the bulk copolymerization of p-t-butylstyrene (S) and methyl methacrylate (M) were analyzed by ¹H-NMR. The spectra showed fine structure in the δ 2.2–3.6 region similar to that reported for styrene/methyl methacrylate copolymers. Reactivity ratios for S-M copolymers determined by classical composition measurements differed markedly from the same ratios determined by NMR when it was assumed that NMR peak-triad assignments could be made by analogy with published styrene/methyl methacrylate assignments. A new set of peak-triad assignments was proposed that reconciles this difficulty and gives good agreement between triad fractions measured by NMR and those calculated from theory.     

Synthesis and properties of cyclopropane-containing optically transparent polymers

New cyclopropane-containing optically transparent polymers were prepared by radical homopolymerization of p-(2-methoxycarbonylcyclopropyl)styrene and by its binary copolymerization with styrene and methyl methacrylate. The composition and structure of these macromolecular compounds were determined, and their main service characteristics were evaluated.     

Effect of the Medium on the (Co)polymerization Kinetics and Properties of N-Vinyl-3(5)-methylpyrazole (Co)polymers

The kinetics of homopolymerization of N-vinyl-3(5)-methylpyrazole, its copolymerization with vinyl acetate, 2-hydroxyethyl methacrylate, and acrylic acid, as influenced by the reaction medium, were studied. The properties of the resulting (co)polymers were determined.     

General Method for Evaluation of Alternating Tendency in Copolymerization

A new method for deriving expressions for the mole fractions of alternating n-ads and the average lengths of the alternating sequences of n-component copolymers (n > 2) was developed based on the apparatus of finite Markov chains. These characteristics are considered as indexes of alternating tendency forn-component copolymerization. A specific property of n-component copolymerization (n > 3) compared with binary copolymerization is the fact that alternating n-ads might be constructed by two, three, or more types of monomeric units. In order to express this specific property of three and multi-component copolymers the term, alternating order, is introduced. The method developed in the paper permits the alternating indexes to be determined differentially in dependence of alternating order. Expressions for the average lengths and the compositions of all possible alternating sequences starting with a given monomer unit and ending with unit found only at that position, are derived as well. The alternating indexes for binary radical copolymerization of styrene and methyl methacrylate and for ternary radical copolymerization of styrene, methyl methacrylate, and acrylonitrile were determined.     

Preparation and polymerization of thyroxine methacrylate monomers

Thyroxine methyl ester amides of mono-, di-, and tri-glycyl methacrylates have been prepared. Water-soluble polymers formed from thyroxine methacrylate monomers by free-radical copolymerization with acrylamide had molecular weights of (2–4) × 10⁴ (by viscometry). A fluorescent polymer was prepared by copolymerization with a fluorescein methacrylate monomer. Similarly, a polymeric thyroxine material was prepared with amine functionality by copolymerization with N-3-aminopropylmethacrylamide. These polymers may have interesting biological and immunochemical properties.     

Anionic polymerization and copolymerization of S-methyl thiomethacrylate

S-Methyl thiomethacrylate (methyl thiolmethacrylate, MTMA) was polymerized with a variety of anionic initiators such as n-BuLi, octylpotassium, PhMgBr, and Et₂AlNPh₂ in toluene and THF. Stereoregularity of the polymer (PMTMA) was determined from the ¹H-NMR spectrum of poly(methyl methacrylate), which had been derived from PMTMA, because the α-methyl resonance in the ¹H-NMR spectrum of PMTMA was not satisfactorily solved owing to the overlap of pentad signals. The ¹³C-NMR spectrum of PMTMA also showed the splitting due to pentad sequences. Stereoregularity of PMTMA was always low compared with that of poly(methyl methacrylate), which was prepared under the same reaction conditions. MTMA was much more reactive than methyl methacrylate and methacrylonitrile in the copolymerization with n-BuLi in toluene and in THF at ?78°C. The lower stereoregulation of the polymerization of MTMA and the higher reactivity of MTMA were mainly ascribed to the higher resonance effect of MTMA.     

Hydrophilic and hydrophobic copolymer systems based on acrylic derivatives of pyrrolidone and pyrrolidine

This article deals with the synthesis of hydrophilic methacrylic monomers derived from ethyl pyrrolidone [2‐ethyl‐(2‐pyrrolidone) methacrylate (EPM)] and ethyl pyrrolidine [2‐ethyl‐(2‐pyrrolidine) methacrylate (EPyM)] and their respective homopolymers. For the determination of their reactivity in radical copolymerization reactions, both monomers were copolymerized with methyl methacrylate (MMA), the reactivity ratios being calculated by the application of linear and nonlinear mathematical methods. EPM and MMA had ratios of r_EPM = 1.11 and r_MMA = 0.76, and this indicated that EPM with MMA had a higher reactivity in radical copolymerization processes than vinyl pyrrolidone (VP; r_VP = 0.005 and r_MMA = 4.7). EPyM and MMA had reactivity ratios of r_EPyM = 1.31 and r_MMA = 0.92, and this implied, as for the EPM–MMA copolymers, a tendency to form random or Bernoullian copolymers. The glass‐transition temperatures of the prepared copolymers were determined by differential scanning calorimetry (DSC) and were found to adjust to the Fox equation. Total‐conversion copolymers were prepared, and their behavior in aqueous media was found to be dependent on the copolymer composition. The swelling kinetics of the copolymers followed water transport mechanism case II, which is the most desirable kinetic behavior for a swelling controlled‐release material. Finally, the different states of water in the hydrogels—nonfreezing water, freezing bound water, and unbound freezing water—were determined by DSC and found to be dependent on the hydrophilic and hydrophobic units of the copolymers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 395–407, 2003     

N-[4-(磺酰胺)苯基]丙烯酰胺与丙烯腈、甲基丙烯酸甲酯共聚合的竞聚率

N-[4-(磺酰胺)苯基]丙烯酰胺(ASPAA)单体可以均聚或与其它单体共聚合成具有药理活性的聚合物，制成水溶性、毒副作用小、具有缓释作用的大分子药物．同时，由于磺酰胺基具有一定的碱溶性，ASPAA与丙烯酸酯类等单体的共聚物可用于制备可碱显影、显影宽容度和耐印力等性能良好的平印、计算机直接制版版材．有关ASPAA与其它单体共聚的竞聚率还鲜见报道．本文在合成ASPAA单体的基础上，对ASPAA／丙烯腈和ASPAA／甲基丙烯酸甲酯共聚的竞聚率进行了研究。     

Synthesis and flocculation performance of graft copolymer of <Emphasis Type="Italic">N</Emphasis> -vinylformamide and poly(dimethylaminoethyl methacrylate) methyl chloride macromonomer

 A comb-structured polymeric flocculant was synthesized by the aqueous copolymerization of N-vinylformamide (NVF) with poly(dimethylaminoethyl methacrylate) quats (methyl chloride) macromonomer. The effects of temperature and macromonomer concentration on the copolymerization kinetics were determined experimentally. The copolymerization reactivity ratio was measured to be 3.82 and 6.39 for NVF and macromonomers with 50 and 100 repeating units when copolymerized with NVF. The copolymer samples were also subjected to a flocculation performance test and were found to be more effective than linear random cationic copolymers in terms of cationic content, flocculation rate, final turbidity levels, and floc strength. Received: 11 June 2001 Accepted: 9 August 2001     

Synthesis and properties of water‐soluble azlactone copolymers

Preparation and study of a series of copolymers incorporating 2‐vinyl‐4,4‐dimethylazlactone (VDMA) is reported. The reactivity ratios for photo‐initiated free radical copolymerization of VDMA with methacrylic acid (MAA), acrylic acid (AA), acrylamide (AAm), dimethylacrylamide (DMAA), hydroxyethyl methacrylate (HEMA), methoxy poly(ethylene glycol) methacrylate (MPEG₃₀₀MA), and 2‐methacryloyloxyethyl phosphorylcholine (MPC), were determined by fitting comonomer conversion data obtained by in situ ¹H NMR to a terminal copolymerization equation. Semi‐batch photo‐copolymerizations were then used to synthesize the corresponding VDMA copolymers with constant composition. Their solubility and dissolution behavior, as well as their hydrolysis half‐lives under physiological conditions, were determined. P(VDMA‐co‐MAA) copolymers with 52 to 93 mol % VDMA showed decreasing initial solubility and increasing hydrolysis half‐lives with increasing VDMA content. VDMA copolymers with nonionic monomers AAm and DMAA were water soluble only at VDMA contents of 41 and 22 mol % or less, respectively, and showed longer hydrolysis half‐lives than comparable MAA copolymers. VDMA copolymers with HEMA and MPEG₃₀₀MA were found to crosslink during storage, so their hydrolysis half‐lives were not determined. VDMA copolymers with 18% zwitterionic MPC showed a much longer half‐life and superior initial solubility compared to analogous p(VDMA‐co‐MAA), identifying this copolymer as a promising candidate for macromolecular crosslinkers in, for example, aqueous layer‐by‐layer co‐depositions with polyamines. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Novel salep‐based chelating hydrogel for heavy metal removal from aqueous solutions

A novel optimized chelating hydrogel was synthesized via graft copolymerization of acrylamide and 2‐hydroxyethyl methacrylate (as two‐dentate chelating co‐monomer) onto salep (a multicomponent polysaccharide obtained from dried tubers of certain natural terrestrial orchids) using N,N′‐methylenebisacrylamide as a crosslinker and ammonium persulfate as an initiator. Reaction parameters (N,N′‐methylenebisacrylamide and ammonium persulfate amounts as well as acrylamide/2‐hydroxyethyl methacrylate weight ratio) affecting the water absorption of the chelating hydrogel were optimized using a systematic method to achieve a hydrogel with high swelling capacity as possible. Heavy metal ion adsorption capacity of the optimized hydrogel for metal ions [Cu (II), Pb (II), Cd (II), and Cr (III)] were investigated in aqueous media containing different concentrations of these ions (5–50 ppm). The results showed that the hydrogel have great potential for heavy metal removal from aqueous solutions. The hydrogel formation was confirmed by Fourier transform infrared spectroscopy, and surface morphology study of the hydrogel was performed by scanning electron microscope. Copyright © 2016 John Wiley & Sons, Ltd.     

Thermoresponsive hyperbranched polymers via In Situ RAFT copolymerization of peg‐based monomethacrylate and dimethacrylate monomers

Here we report the preparation of PEG‐based thermoresponsive hyperbranched polymers via a facile in situ reversible addition‐fragmentation chain transfer (RAFT) copolymerization using bis(thiobenzoyl) disulphide to form 2‐cyanoprop‐2‐yl dithiobenzoate in situ. This novel one‐pot in situ RAFT approach was studied firstly using methyl methacrylate (MMA) monomer, then was used to prepare thermoresponsive hyperbranched polymers by copolymerization of poly(ethylene glycol) methyl ether methacrylate (PEGMEMA, M_n = 475), poly(propylene glycol) methacrylate (PPGMA, M_n = 375) and up to 30 % of ethylene glycol dimethacrylate (EGDMA) as the branching agent. The resultant PEGMEMA‐PPGMA‐EGDMA copolymers from in situ RAFT were characterized by Gel Permeation Chromatography (GPC) and ¹H‐NMR analysis. The results confirmed the copolymers with multiple methacrylate groups and hyperbranched structure as well as RAFT functional residues. These water‐soluble copolymers with tailored compositions demonstrated tuneable lower critical solution temperature (LCST) from 22 °C to 32 °C. The phase transition temperature can be further altered by post functionalization via aminolysis of RAFT agent residues in polymer chains. Moreover, it was demonstrated by rheological studies and particle size measurements that these copolymers can form either micro‐ or macro photocrosslinked gels at suitable concentrations due to the presence of multiple methacrylate groups. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3751–3761