Methyl Methacrylate-8-quinolinyl Acrylate Copolymers-II: Ion-exchange Study

Abstract

The chelating ion-exchange properties of the methylmethacrylate (MMA)-8-quinolinyl acrylate (8-QA) copolymers, synthesized using different monomer feed ratios, were estimated by batch equilibration method. Five metal ions viz., Cu⁺²,Ni⁺²,Co⁺², Zn⁺² and Fe⁺³ were used to evaluate the capability of MMA-8-QA copolymers as a cation exchangers. The ion-exchange study was carried out under three different experimental variables viz., pH of the aqueous medium, electrolyte and its ionic strength and shaking time. It was observed that due to the presence of a pendant ester-bound quinolinyl group, the copolyraers are capable of exchanging the tested cations from their aqueous solutions.     

Synthesis, degradation and in vitro controlled drug release of novel copolymers of 5-methyl-5-methoxycarbonyl-1,3-dioxan-2-one and caprolactone

Novel biodegradable copolymers of 5-methyl-5-methoxycarbonyl-1,3-dioxan-2-one (MMTC) and caprolactone (CL) were synthesized under different conditions by ring-opening polymerization. The structure of the resultant copolymers was characterized by IR, ¹H NMR and ¹³C NMR methods. Their molecular weight was measured by gel permeation chromatography (GPC). Incorporating the MMTC units into PCL main chain results in the great enhancement of hydrolytic degradation rate and the effective retardance of release rate of Tegafur in comparison with the PCL homopolymer. The enzymatic degradation rate increases with increasing the molar content of PCL, and the copolymers degrade faster in the presence of pseudomonas (PS) lipase than that in the absence of PS lipase. Some mechanical properties of the copolymers were tested and showed that they can be adjusted by varying the composition of the copolymers.     

Acrylic Homo- and Co-polymers Based on 2, 4-dichlorophenyl Methacrylate and 8-quinolinyl Methacrylate

The monomer 2, 4-dichlorophenyl methacrylate (2,4-DMA) was synthesized from 2, 4-dichlorophenol and characterized by conventional methods. The homopolymers of 2,4-dichlorophenyl methacrylate and its copolymers with 8-quinolinyl methacrylate (8-QMA) in different feed ratio were prepared by free radical polymerization using dimethyl formamide (DMF) as a solvent and 2,2-azobis iso butyronitrile (AIBN) as an initiator. The resulting polymers were characterized by using IR spectroscopy. Reactivity ratios of monomer were evaluated using UV-spectroscopy. Average molecular weights and polydispersity were determined by gel permeation chromatography (GPC). Solution viscosity was also obtained. The thermal analysis was carried out using TGA and DSC. The homo- and co-polymers were also tested for their antimicrobial properties against selected microorganism. The metal ion uptake capacity of synthesized copolymers was estimated by batch equilibration method using different metal ion solution under different experimental conditions. It is observed that due to the presence of pendant ester bound quinoline group, the copolymers are capable of adsorbing cations from their aqueous solution.     

Statistical Copolymers of l,l-lactide and ε-caprolactone

Summary Copolymers of l,l-lactide with -caprolactone have been investigated in order to develop valuable biodegradable materials for medical applications. The syntheses of homopolymers and copolymers of l,l-lactide and -caprolactone by ring-opening bulk polymerization were performed using stannous octoate as initiator at 120 °C. The compositions of the copolymers were systematically varied by polymerization of monomer mixtures containing from 10 to 90 95 of -caprolactone, at 10% step of variation. High polymerization conversions were observed for homopolymers and copolymers syntheses. Synthesized products were characterized by gel permeation chromatography (GPC) and nuclear magnetic resonance spectrometry (NMR). The analyses of the segment lengths by ¹³C-NMR spectroscopy indicated the predominance of random copolymers formation and the transesterification reaction was not detected.     

Fabrication,structures, and properties of acrylonitrile/methyl acrylate copolymers and copolymers containing microencapsulated phase change materials

The polyacrylonitrile‐methyl acrylate (AN/MA mole ratio 100/0–70/30) copolymers and copolymers (AN/MA mole ratio 85/15) containing up to 40 wt % of microencapsulated n‐octadecane (MicroPCMs) are synthesized in water. The MicroPCMs were incorporated at the step of polymerization. The effect of the MA mole ratio and MicroPCMs content on structures and properties of the copolymers were studied by using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (¹H NMR), scanning electronic microscope (SEM), differential scanning calorimetry (DSC), thermogravimetry analysis (TG), gel permeation chromatography (GPC), and X‐ray diffraction (XRD). The feeding ratio agreed well with the composition of the AN/MA copolymers. The copolymers are synthesized in the presence of MicroPCMs. The melting point moves to lower temperature (206°C), while the decomposition temperature moves to higher temperature (309°C) with increasing of the MA mole ratio and microcapsules content. The number–average molecular weight of the copolymer is ～30,000. The crystallinity of the copolymer decreases with increasing of the MA mole ratio and microcapsules content. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2776–2781, 2007     

Synthetic control of sequence distribution in PDPS/PDMS copolymers

Very narrow molecular weight distributed poly(dimethylsiloxane-co-diphenylsiloxane) copolymers with different sequence distribution have been synthesized through ring-opening copolymerization under kinetically controlled conditions. The sequence distribution of the monomer units in the copolymers was determined by high resolution¹H NMR spectroscopy and the monomer reactivity ratios. The copolymers were also characterized by GPC and DSC analysis. The systematic variance in thermal transitions confirmed the assignment of the monomer sequencing in the copolymers.     

Syntheses and Properties of Novel Copolymers of Polylactide and Aliphatic Polycarbonate Based on Ketal-Protected Dihydroxyacetone

The novel random copolymers of L-LA and 2, 2-ethylenedioxy-1, 3-propanediol carbonate (EOPDC) were synthesized in bulk using Sn(Oct)₂ as a catalyst. The poly(EOPDC -co- L-LA)s obtained were characterized by FT IR, ¹H NMR, ¹³C NMR, GPC and DSC. The copolymers were obtained with yield of 87.9–95.6%. The number average molecular weight of the copolymer is 1.85–6.18 × 10⁴ with a polydispersity of 1.41–1.73. The properties of the copolymer including the enzymatic degradation by proteinase K and drug-controlled release property were also investigated. The results show that the degradation rate of the copolymers increases with increasing LA content in the copolymers.     

Styrene–isoprene block copolymers. II. Hydrogenation and solution properties

Styrene–isoprene block copolymers with a different degree of monomer distribution are hydrogenated with homogeneous catalysts. The products are characterized by means of IR and ¹H-NMR spectroscopy, GPC, viscometry, and light scattering. Hydrogenation proceeds without destruction and selectively for olefinic unsaturation. The hydrogenated copolymers are homogeneous in molecular weights and chain composition. The influence of the copolymer structure on the solution properties in selective solvents is established. In cyclohexane an equilibrium between micelle associates and individual polymer coils, monomolecular micelles, or micelle aggregates are observed, depending on the type of the copolymer. The micellization in base-lubricating oil leads to micelle fractions with a different degree of association.     

Spontaneous copolymerization of N-(2-hydroxyethyl)ethyleneimine with maleic anhydride

Summary The copolymerization of N-(2-hydroxyethyl)ethyleneimine, (HEEI) as nucleophilic monomer and maleic anhydride (MA) as electrophilic monomer in the absence of initiator in acetonitrile was investigated. Copolymers were characterized by IR, ¹H-NMR and ¹³C-NMR spectroscopy. The copolymer composition depends on the monomer ratio in the feed, determined by ¹H-NMR spectroscopy. The presence of MA bridges between copolymer chains was established by spectroscopic analysis. At lower temperature the yield and molecular weight of copolymers decrease as well as the MA unit content in the copolymer.     

Homopolymer of 4-chloro-3-methyl Phenyl Methacrylate and its Copolymers with Butyl Methacrylate: Synthesis, Characterization, Reactivity Ratios and Antimicrobial Activity

The methacrylate monomer 4-chloro-3‐methyl phenyl methacrylate (CMPM) was synthesized by reacting 4-chloro-3‐methyl phenol with methacryloyl chloride. The homopolymer and various copolymers of CMPM with n-butyl methacrylate were synthesized by free-radical polymerization in toluene at 70°C using 2,2′-azobis(isobutyronitrile) as the initiator. The CMPM monomer was characterized by Fourier transform IR and ¹H-NMR studies. The copolymers were characterized by IR spectroscopy. The molecular weights (M _n and M _w) and the polydispersity index were obtained from gel permeation chromatography. The solubility and intrinsic viscosity of the homopolymer and the copolymers are also discussed here. The copolymer composition obtained from UV spectra led to the determination of reactivity ratios employing Fineman-Ross and Kelen-Tudos linearization methods. Thermogravimetric analyses of the homopolymer and the copolymers were carried out under a nitrogen atmosphere. The homopolymer and the copolymers prepared were tested for their antimicrobial activity against bacteria, fungi and yeasts.     

Copolymers of a new methacrylate monomer bearing oxime ester and ether with methyl methacrylate: Synthesis,characterization, monomer reactivity ratios,and biological activity

The free‐radical copolymerization of 2‐metil‐1‐{[(1‐{4‐[(4‐nitrobenzil)oksi]fenil}etilidene)amino]oksi}prop‐2‐en‐1‐on (NBOEMA) with methyl methacrylate (MMA) was carried out in 1,4‐dioxane at 65 ± 1°C. The copolymers were analyzed by Fourier transform infrared spectroscopy, ¹H‐NMR, ¹³C‐NMR, and gel permeation chromatography (GPC). Elemental analysis was used to determine the molar fractions of NBOEMA and MMA in the copolymers and for the characterization of the compounds. The monomer reactivity ratios were calculated according to the general copolymerization equation with the Kelen–Tudos and Fineman–Ross linearization methods. The polydispersity indices of the polymers, determined with GPC, suggested a strong tendency for chain termination by disproportionation. The thermal behaviors of the copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. The glass‐transition temperature of the copolymers increased with increasing NBOEMA content in the copolymers. Also, the apparent thermal decomposition activation energies were calculated by the Ozawa method with a Shimadzu TGA 60H thermogravimetric analysis thermobalance. All of the products showed moderate activity against different strains of bacteria and fungi. The photochemical properties of the polymers were investigated by UV spectroscopy. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Copolymerization of styrene and maleic anhydride in supercritical carbon dioxide

The copolymerization of styrene (St) and maleic anhydride (MA) was carried out in supercritical carbon dioxide (SC CO₂). It was found that St and MA are easy to copolymerize in SC CO₂ and the conversion can reach 97%, and that very fine and dry powders are obtained. The products were characterized using Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). GPC data showed that the molecular weight of the copolymer reach 3.62 × 10⁴ g mol^?1. Scanning electron microphotographs showed the minimum particle size of the product is about 200 nm. DSC measurements indicated that the glass transition temperature (T_g) of the copolymer increases with increasing the MA content in the copolymer. TGA curve showed that the copolymers were decomposed at about 350°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Copolymerization without initiator of 1-(2-hydroxyethyl)aziridine and acrylamide

Summary 1-(2-Hydroxyethyl)aziridine as nucleophilic monomer was copolymerized in the absence of an initiator under various experimental conditions with acrylamide as electrophilic monomer. All copolymers were characterized by elemental analysis, IR, and ¹H-NMR spectroscopy. The viscosity measurements showed that the copolymers behave as polyelectrolytes. The copolymer composition was determined from elemental analysis and ¹H-NMR spectra.     

One‐step synthesis of star‐block copolymers via simultaneous free radical polymerization of styrene and ring opening polymerization of ε‐caprolacton using tetrafunctional iniferter

Star‐block copolymers comprised of poly(styrene) (S) core and four poly(ε‐caprolacton) (ε‐CL) arms were synthesized by the combination of free radical polymerization (FRP) of S and ring opening polymerization (ROP) of ε‐CL in one‐step in the presence of tetrafunctional ineferter. The block copolymers were characterized by ¹H‐NMR and FTIR spectroscopy, gel permeation chromatography (GPC), and fractional precipitation method. ¹H ‐NMR and FTIR spectroscopy and GPC studies of the obtained polymers indicate that star‐block copolymers easily formed as result of combination FRP and ROP in one‐step. The γ values (solvent/precipitant volume ratio) were observed between 1.04–2.72 (mL/mL) from fractional measurements. The results show that when the initial S feed increased, the molecular weights of the star‐block copolymers also increased and the polydispersities of the polymers decreased. M_w/M_n values of the products were measured between 1.4 and 2.86 from GPC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Novel poly(ε-caprolactone)s bearing amino groups: Synthesis,characterization and biotinylation

A novel functional ε-caprolactone monomer containing protected amino groups, γ-(carbamic acid benzyl ester)-ε-caprolactone (γCABεCL), was successfully synthesized. A series of copolymers [poly(CL-co-CABCL)] were prepared by ring-opening polymerization of ε-caprolactone (CL) and γCABεCL in bulk using tin (II)-2-ethylhexanoate [Sn(Oct)₂] as catalyst. The morphology of the copolymers changed from semi-crystalline to amorphous with increasing γCABεCL monomer content. They were further converted into deprotected copolymers [poly(CL-co-ACL)] with free amino groups by hydrogenolysis in the presence of Pd/C. After deprotection, the free amino groups on the copolymer were further modified with biotin. The monomer and the corresponding copolymers were characterized by ¹H NMR, ¹³C NMR, FT-IR, mass, GPC and DSC analysis. The obtained data have confirmed the desired monomer and copolymer structures.     

Facile synthesis of oxidative copolymers from aminoquinoline and anisidine

Oxidative copolymerization of 8-aminoquinoline (AQ) and o-anisidine (AS) using ammonium persulfate as oxidant was studied under various polymerization conditions and fine and uniform copolymer particles of several micrometers, determined by laser particle size and atomic force microscopic analyses, were synthesized simply. The polymerization yield, molecular weight, solubility, electroconductivity, and thermostability of the copolymers were systematically studied by changing the comonomer ratio, polymerization temperature, monomer/oxidant ratio, and acidic medium. Single chain configuration of the copolymers with various AQ/AS ratios was simulated and well related to the intrinsic viscosity. The macromolecular structure of the resulting copolymers was wholly characterized by elementary analysis, IR, UV-vis, high-resolution ¹H NMR, and solid-state high-resolution ¹³C NMR. The results show that the oxidative copolymerization of AQ and AS is exothermic. All copolymers are totally soluble in H₂SO₄, HCOOH, m-cresol but their solubility in other solvents depends significantly on the comonomer ratio, and also on the polymerization conditions. The oxidative polymer obtained is a real copolymer containing AQ and AS units rather than a mixture of two homopolymers. The AQ content calculated based on the ¹H NMR spectra of the copolymers is slightly higher than feed AQ content when feed AQ content is lower than 70 mol%. However, the AQ content calculated based on the ¹³C NMR and elementary analyses is lower than the feed AQ content when the AQ feed content is higher than 50 mol%. A peculiar dependency of molecular weight and electroconductivity of the copolymers on the AQ/AS ratio was observed. The decomposition temperature of the copolymers rises with increasing AQ content. Therefore, the thermostability of the copolymers increases with increasing AQ content due to its high aromaticity.     

Copolymerization of bromophenylmaleimide with ethyl or butyl methacrylate

N‐p‐Bromophenylmaleimide (BrPMI) does not polymerize in solution by conventional free radical mechanism. However, it readily polymerized in bulk when mixed with a free radical initiator and heated in a microwave oven for 7–8 min. Copolymerization of ethyl methacrylate or butyl methacrylate with BrPMI was conducted in dioxane. The copolymers were characterized by IR and ¹H NMR spectroscopy and gel permeation chromatography. The monomer reactivity ratios were calculated by a non‐linear least‐square analysis. Thermal analysis indicated a great improvement in thermal stability of the copolymers compared with the methacrylate homopolymers. BrPMI was also polymerized in bulk in the DSC pan, which allowed the calculation of the activation energy of its polymerization. Copyright © 2003 Society of Chemical Industry     

Application of GPC in the Study of Stereospecific Block Copolymers

Abstract

Three different techniques involved in the preparation of Stereospecific block copolymers were studied using gel permeation chromatography (GPC). These techniques involved the use of a monofunctional organo-lithium catalyst, a difunctional organolithium catalyst, and a combination of a monofunctional organolithium catalyst and a coupling technique. GPC curves were obtained on the block copolymers using two different column sequences and solvents. The ABA block copolymers studied contained styrene, vinyl toluene, or α-methyl styrene as thermoplastic monomers and butadiene as the elastomeric monomer. The results obtained showed that block copolymers prepared using monomers and catalyst systems free of impurities generally exhibited single peaked GPC curves. In systems where impurities were found to be present, small amounts of A block homopolymer and AB block copolymer were formed. In such cases, the GPC curves were observed to have two or three peaks.     

Copolymerization of 4-cyanophenyl methacrylate with methyl methacrylate: Synthesis,characterization and determination of monomer reactivity ratios

Summary A novel methacrylic monomer, 4-cyanophenyl methacrylate (CPM) was synthesized by reacting 4-cyanophenol dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine as a catalyst. Copolymers of CPM with methyl methacrylate(MMA) at different composition was prepared by free radical solution polymerization at 70±1 °C using benzoyl peroxide as initiator. The copolymers were characterized by FT-IR, ¹H-NMR and ¹³C-NMR spectroscopic techniques. The solubility of the polymers was tested in various polar and non polar solvents. The molecular weight and polydispersity indices of the copolymers were determined using gel permeation chromatography. The glass transition temperature of the copolymers increases with increase in mole fraction of MMA content. The thermal stability of the copolymer increases with increases in mole fraction of CPM content in the copolymer. The copolymer composition was determined by using ¹H-NMR spectroscopy. The monomer reactivity ratios estimated by the application of linearization methods such as Fineman-Ross (r₁=2.524±0.038, r₂=0.502±0.015), Kelen-Tudos (r₁=2.562±0.173, r₂=0.487±0.005) and extended Kelen-Tudos methods (r₁=2.735±0.128, r₂=0.4915±0.007).     

Graft copolymers of lignin from straw with 1‐ethenylbenzene: Synthesis and characterization

The synthesis of copolymers between lignin from steam‐exploded straw and 1‐ethenylbenzene is described. Beforehand, lignin from steam‐exploded straw was fully characterized by using elemental analysis, ultraviolet spectroscopy, gel permeation chromatography (GPC), Fourier transform infrared (FTIR), and both ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy. Using a previously described procedure utilizing calcium chloride and hydrogen peroxide as reagents the synthesis of the copolymers was performed. FTIR of the copolymers showed the presence of both lignin and polystyrene. GPC analysis showed the presence of a fraction with high molecular weights. These results were confirmed from both viscosity data and differential calorimetry. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 72–79, 2001