Polymers of vinylphosphonic acid,acrylonitrile, and methyl acrylate and their nanofibers

In this study, a small amount of vinylphosphonic acid was used to produce fire-retardant copolymers and terpolymers from acrylonitrile and methyl acrylate. The structures of copolymer and terpolymers were elucidated by ¹H-NMR and phosphorous analysis. Thermal decomposition of vinylphosphonic acid-containing copolymers and terpolymers started at lower temperatures than of poly(acrylonitrile-co-methyl acrylate). Methyl acrylate contributes to the thermal resistance of the terpolymers. Poly(acrylonitrile-co-methyl acrylate-co-vinylphosphonic acid) with a phosphorous content about 0.25% burned at a slower rate and emitted less smoke compared to poly(acrylonitrile-co-methyl acrylate). The burning tests showed that both copolymer and terpolymers containing vinylphosphonic acid behaved as a fire-retardant polymer. The phosphonate and phosphonic acid groups in the copolymer and terpolymers accelerate the cyclization of nitrile groups and inhibit the fire in the gas phase. Nanofibers were successfully produced by the electrospinning method from the copolymers and terpolymers containing vinylphosphonic acid moiety.     

Synthesis,characterization and corrosion protection properties of poly(N-vinyl carbazole-co-glycidyl methacrylate) coatings on low nickel stainless steel

Methacrylate based copolymers are considered as one of the best organic coating materials for anticorrosive application. Poly(N-vinyl carbazole-co-glycidyl methacrylate) have been synthesized by free radical solution polymerization technique from different mole ratios of N-vinyl carbazole (N-Vc) and glycidyl methacrylate (GMA) and characterized using Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (¹H NMR and ¹³C NMR). Thermal analyses of the poly(N-Vc-co-GMA) were performed by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The number average molecular weight (M_n) of different compositions of the same was determined by gel permeation chromatography (GPC). The corrosion performances of low nickel stainless steel specimens coated with different composition of copolymers were investigated in 1 M H₂SO₄ using potentiodynamic polarization, electrochemical impedance spectroscopic (EIS) method, scanning electron microscopic (SEM) and energy dispersive X-ray analysis (EDAX). Poly(N-Vc-co-GMA) have been provided in order to achieve adherent, low permeability to aggressive ions as well as environmentally favored good anticorrosive coating. Electrochemical corrosion test and surface analysis results clearly showed that poly(N-Vc-co-GMA) coatings served as a stable host matrix on low nickel stainless steel against corrosion. It was also observed that the coatings of poly(N-Vc-co-GMA) with equal mole ratio of N-Vc and GMA exhibited the best corrosion resistance among all combinations.     

Influence of electrochemically prepared poly(pyrrole-co-N-methyl pyrrole) and poly(pyrrole)/poly(N-methyl pyrrole) composites on corrosion behavior of copper in acidic medium

Poly(pyrrole-co-N-methyl pyrrole) copolymer and poly(pyrrole)/poly(N-methyl pyrrole) bilayer composites were electrochemically synthesized on copper by cyclic voltammetry from aqueous solution of 0.3 M oxalic acid and 0.1 M monomer. Synthesis of copolymers were performed with different monomer feed ratios (pyrrole:N-methyl pyrrole, 8:2, 6:4, 5:5, 4:6 and 2:8) and in order to determine the copolymer, which has the best corrosion performance, anodic polarization was applied to copolymer coated samples. It was found that the performance of coatings was strongly dependent to the monomer feed ratio and the copolymer synthesized with 8:2 concentration ratio showed the most protective property compared to others. Bilayer of poly(pyrrole)/poly(N-methyl pyrrole) was also synthesized to compare the anticorrosive properties. Polymer films were characterized by ATR-FTIR spectroscopy and SEM techniques. Corrosion behavior of polymer composites was investigated in 0.1 M H₂SO₄ solution by anodic polarization and electrochemical impedance spectroscopy. Different approaches such as phase angle at high frequency and areas under Bode plots were used to evaluate corrosion performances of the coatings. Copolymer and bilayer coatings were found to have higher protection effect than single polypyrrole coatings. Moreover, bilayer coating exhibited better protection efficiency than copolymer coating against corrosion of copper when the obtained results were compared.     

Thermal properties, specific interactions, and surface energies of PMMA terpolymers having high glass transition temperatures and low moisture absorptions

We have prepared a series of poly(methyl methacrylate) (PMMA)-based terpolymers that have high glass transition temperatures and low moisture absorptions by the free radical copolymerization of methyl methacrylate, methacrylamide, and styrene in dioxane. We have investigated the effects of the styrene content on the glass transition temperatures, hydrogen bonding interactions, surface energies, moisture absorption, and molecular weights of these poly(methyl methacrylate-co-methacrylamide-co-styrene) (Poly(MMA-co-MAAM-co-S)) terpolymers by differential scanning calorimetry, Fourier transform infrared and X-ray photoelectron spectroscopies, contact angle measurements, and gel permeation chromatography. The results indicate that the glass transition temperatures, hydrogen bonding strengths, surface energies, molecular weights, and the moisture absorption decreased upon increasing the PS content in most of the terpolymer systems. In addition, the moisture absorptions of some selected terpolymers decreased even through they possess higher values of T_g than pure PMMA. These selected terpolymers have the potential to replace pure PMMA in optical device applications.     

Design of responsive double-hydrophilic A-b-(B-co-C) diblock terpolymers with tunable thermosensitivity

Double-hydrophilic poly[(oligo(ethylene glycol) methacrylate)-co-methyl methacrylate]-b-poly(2-(diethylamino)ethyl methacrylate), P(EGMA-co-MMA)-b-PDEA, diblock terpolymers were designed and explored in aqueous media. Thanks to the thermosensitivity of the P(EGMA-co-MMA) statistical block and the pH sensitivity of the PDEA block, these terpolymers form two distinct micellar self-assemblies at different conditions of pH and temperature. The thermosensitivity of these terpolymers can be tuned by controlling the LCST of the statistical block through its monomer unit composition.     

A novel route for the synthesis of poly(2-hydroxyethyl methacrylate-co-methyl methacrylate) grafted titania nanoparticles via ATRP

A new method is presented for grafting poly(2-hydroxyethyl methacrylate-co-methyl methacrylate) (P(HEMA-co-MMA)) chains from the surface of TiO₂ nanoparticles via atom transfer radical polymerization (ATRP). First, the ATRP initiators were immobilized onto the TiO₂ surface by using 3-aminopropyltriethoxysilane coupling agent and 2-bromoisobutyryl bromide. Then the copolymerization of 2-hydroxyethyl methacrylate with methyl methacrylate was initiated and propagated on the TiO₂ surface by ATRP. The resulting composite nanoparticles were characterized by means of XPS, FT-IR, ¹H NMR, GPC and TGA. The results indicated that the grafting of copolymer chains from the TiO₂ surface was successful. This method opens up new avenues for the preparation of TiO₂-polymer nanocomposites.     

Synthesis of Poly(maleic anhydride-co-taurine) as a Biodegradable Detergent Builder

Biodegradable poly(maleic anhydride-co-taurine) was synthesized by anionic ring-opening copolymerization of maleic anhydride (MA) and taurine. The structures were characterized by elemental analysis, Fourier transform infrared spectroscopy, nuclear magnetic resonance (¹H NMR) and mass spectroscopy. The weight-average molecular weight (M _w) of the copolymers was tested using multi-angle laser light scattering instrument. The biodegradability of the copolymers was judged by the shaking table test method. The possibility of the copolymers to be a detergent builder was assessed in terms of the calcium sequestration capacity which was evaluated in accordance with the China National Standard method (GB/T 21884-2008) and dispersive power test. The results showed that the copolymers were biodegradable, and possessed a high calcium sequestration capacity and a good dispersancy, which were environment-friendly detergent builders.     

Anti-corrosive properties of poly (2-pyridylamine-co-aniline-co-2,3-xylidine) terpolymer coating on mild steel in different corrosive environments

A soluble terpolymer from 2-pyridylamine (2PA), aniline (AN) and 2,3-xylidine (XY), poly (2PA-co-AN-co-XY) was synthesized by chemical oxidative polymerization using ammonium persulfate as an oxidant in hydrochloride aqueous medium. The two copolymers, poly (AN-co-XY) and poly (2PA-co-AN) were also synthesized by following identical synthesis route. The resultant terpolymer and copolymers were characterized by Fourier transform infrared (FTIR) and ¹H NMR spectroscopy. The terpolymer and copolymers were chemically deposited on mild steel specimens using N-methyl-2-pyrrolidone (NMP) as solvent via solution evaporation method. The anticorrosive properties of terpolymer and copolymers coatings was investigated in major corrosive environments such as 0.1 M HCl, 5% NaCl solution, artificial seawater, distilled water and open atmosphere by conducting various corrosion tests which include: immersion test, open circuit potential measurements, potentiodynamic polarization measurements, and atmospheric exposure test. The corrosion performance of terpolymer and copolymers coatings was also compared separately with polyaniline (PANi) homopolymer coating. The surface morphology of terpolymer and copolymers coatings was evaluated using scanning electron microscopy (SEM). The synthesized terpolymer exhibited excellent protection against mild steel corrosion; the protection efficiency being in the range of 93–96% after 30 days of immersion. The corrosion performance of individual copolymers was found inferior than the terpolymer. However, the performance of copolymer poly (2AN-co-XY) was found better than copolymer poly (2PA-co-AN).     

Corrosion Protection Behavior of Poly(N-(p-bromophenyl)-2-methacrylamide-co-ethyl methacrylate) Coatings on Low Nickel Stainless Steel

The copolymer poly(N-(pbromophenyl)-2-methacrylamide-co-ethyl methacrylate) has been synthesized by free radical solution polymerization. Thermal stability of the synthesized copolymer was analyzed using thermogravimetric analysis and differential thermal analysis techniques. The corrosion performances of low nickel stainless steel specimens coated with different mole ratios of poly(PBPMA-co-EMA) were investigated with 1 M H₂SO₄ using potentiodynamic polarization, electrochemical impedance spectroscopic studies and chronoamperometric studies. Moreover, all the mole ratios of this copolymer showed good protection against corrosion. Surface and morphological investigation of the product have been studied with the help of scanning electron microscopic, atomic force microscopic, and energy dispersive X-ray analysis techniques, they were used to characterize the adherence and uniformity of the coatings, electrochemical corrosion test and surface analysis results have proved that poly(PBPMA-co-EMA) coatings served as a stable host matrix on low nickel stainless steel as environmentally more favored and best anticorrosive coating.     

Sulfonic Derivatives of 2-Mercaptobenzoxazole and Its Conjugates with Poly(Maleic anhydride-alt-vinyl acetate) with Potential Pharmacological Applications

The results reported represent a continuation of the research on the synthesis of new 2-mercaptobenzoxazole derivatives with potential pharmacological activity and corresponding conjugates prepared by chemical immobilization through ester and amidic bonds onto poly(maleic anhydride-alt-vinyl acetate). New sulfonic compounds derived from 2-mercaptobenzoxazole were synthesized in order to obtain substances with a nucleophilic capacity. Their immobilization on copolymer support, based on poly(maleic anhydride-alt-vinyl acetate) through ester or amidic bonds led to polymer—biologically active principle conjugates with controlled release capacity. Release of the compound immobilized by ester bonds was found to take place in the first 5–6 h. The 2-mercaptobenzoxazole derivatives and the conjugates were characterized using elemental and spectral analysis (FT-IR, ¹H-NMR). Toxicological and antimicrobial tests were performed, recommending some of these therapeutics as candidates for pharmacological applications.     

Radiation-degradation susceptibility studies of vinyl terpolymers: Search for improved electron beam resists

To develop polymer systems with improved lithographic resist properties, terpolymers of methyl methacrylate/methacrylonitrile/methyl α-chloroacryate (MMA/MCN/MCA), methyl methacrylate/methacrylonitrile/α-chloroacrylonitrile (MMA/MCN/ACAN), and methyl methacrylate/methacrylonitrile/vinylidene chloride (MMA/MCN/VDC) were prepared by emulsion polymerization. Also one methyl methacrylate/ methyl α-chloroacylate/α-chloroacrylonitrile (MMA/MCA/ ACAN) terpolymer was prepared. The radiation susceptibilities of these terpolymers were measured using the ⁶⁰Coγ-irradiation method. Molecular weights were determined both by membrane osmometry and gel permeation chromatography. All terpolymers exhibited higher radiation-degradation susceptibilities than poly(methyl methacrylate). The Gs values did not follow the general trend, previously observed with MCN/MCA copolymers, of being directly proportional to the respective terpolymer compositions. In some cases, the addition of small quantities of α-chlorine-containing monomers caused Gx to increase. This observation greatly differs from those observed for copolymer systems such as MMA/MCA, MCN/MCA, MMA/ ACAN, etc. studied previously. Terpolymerization gives highly soluble polymers especially suitable for wet development by many solvents. This is an important consideration for polymers with high mole fractions of methacrylonitrile (MCN) or vinylidene chloride (VDC) which are rendered soluble in development solvents. The electron-beam sensitivities were obtained for samples of three classes of the terpolymers and they were higher than that of PMMA. For example, at 20Kev a 62/34/4 MMA/MCN/MCA terpolymer exhibited a sensitivity of 1.3 × 10^?5 coulombs cm^?2 at l/l_o = 1. The introduction of ACAN narrows the working range for positive resist behavior. For example MMA/MCN/ACAN(41/40/19) has a sensitivity of 8.3 × 10^?6 coulombs cm^?2 at l/l₀ = 0.6 but it crosslinks at 1 ? 1.3 × 10^? coulombs cm². The MMA/MCN/VDC(21/76/3) polymer was about 25 times more sensitive than PMMA (7 × 10^?6 C cm^?2 at l/l₀=1).     

Synthesis of terpolymers having a phospholipid polar group and poly(oxyethylene) in the side chain and their protein adsorption–resistance properties

Terpolymers having phospholipid polar groups were synthesized from 2‐methacryloyloxyethyl phosphorylcholine (MPC), methacryloyl or acryloyl poly(oxyethylene) macromonomers (POEM) [(CH₂CH₂O)_n (where n = 2–23); PEOM(2), PEOM(23), ME(9), Ph(6)], and n‐butyl methacrylate (BMA). The characteristics of these terpolymer membranes were investigated by water content (H) and X‐ray photoelectron spectroscopy. The content of water in the terpolymer increased with increasing content of MPC and length of oxyethylene units. The membranes of terpolymers were found to adsorb bovine serum albumin much less than those of poly(methyl methacrylate) and poly(BMA). Even though the contents of MPC in the terpolymer were 5 to 25 mol %, the terpolymer depressed BSA adsorption more than poly(MPC‐co‐BMA) consisting of 29 mol % of MPC. The use of terpolymer with POEM can decrease the amount of MPC in the polymer. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1092–1105, 2002     

Terpolymerization of Carbon Dioxide with Propylene Oxide and ε-Caprolactone: Synthesis, Characterization and Biodegradability

Summary An aliphatic polycarbonate, terpolymer of carbon dioxide, propylene oxide and ε-caprolactone(PPC-CL-PPO-CL),was synthesized by using a polymer supported bimetallic complex as a catalyst.The terpolymers prepared were characterized by FTIR, ¹H NMR, ¹³C NMR, DSC and WAXD measurements. The influences of various reaction conditions such as molar ratio of the monomers, reaction time and reaction temperature on the terpolymerization progress were investigated. The results showed that ε-caprolactone (ε-CL) was inserted into the backbone of poly(propylene carbonate)-poly(propylene oxide) (PPC-PPO) successfully. The viscosity and glass transition temperature of the terpolymers were much higher than PPC-PPO. ε-Caprolactone offered an ester structural unit that gave the terpolymers remarkable degradability. And the degradation rate of the backbone increased with the ε-CL inserted into the terpolymers.     

Controlled degradation of poly(ethyl cyanoacrylate-co-methyl methacrylate) (PECA-co-PMMA) copolymers

Copolymers of poly(ethyl cyanoacrylate-co-methyl methacrylate) (PECA-co-PMMA) with various compositions were synthesized by free radical bulk polymerization in an effort to control degradation and stability as well as glass transition temperature to overcome intrinsic poor processability of the poly(ethyl cyanoacrylate) (PECA) homopolymer. The copolymers were found to have an alternating random tendency, which was responsible for the efficient inhibition of the unzipping degradation from the polymer chain. Consequently, the stability of the copolymers at elevated temperature and in solution was significantly improved compared to the PECA homopolymer. The glass transition temperatures of the copolymers were lowered by the incorporation of the methyl methacrylate (MMA), thereby further widening the operating temperature range of the polymer. On the other hand, the copolymer films exhibited hydrolytic degradation in phosphate buffered saline (PBS) solution at 37 °C, which is promising for their use as novel biomaterials.     

Migration of additives in polymer coatings: fluorinated additives and poly(vinylidene chloride)-based matrix

In order to combine the properties of polymers based on vinylidene chloride (VC₂) (barrier properties towards many gases) and fluorinated polymers (low surface energy, improvement of the chemical resistance), a diblock terpolymer poly(VC₂-co-MA)-b-(PFDA) was synthesized by RAFT process. The first block is a statistical copolymer of vinylidene chloride (VC₂) and methyl acrylate (MA) (M_n=6800 g mol⁻¹ and PDI=1.4), the second block is a homopolymer of 1H,1H,2H,2H-perfluorodecyl acrylate (FDA). The diblock terpolymer, when used in a coating formulation based on a poly(VC₂-co-MA) matrix, migrates towards the surface of the coating and fluorinated moieties are located at the surface. The migration of the additive was clearly shown by scanning electron microscopy EDX and by measurements of surface energy, and the influence of the nature of the solvents used to prepare the coating was clearly established. These results indicate that the driving force for the migration is the surface energy of the additive.     

The synthesis and evaluation of cyclic olefin sulfone copolymers and terpolymers as electron beam resists

Poly(cyclopentene sulfone) (PCPS) and poly(bicycloheptene sulfone) (PBCHS) copolymers have been evaluated as potential positive electron beam resists which have good thermal properties and which show high sensitivity to ionizing radiation. It was found that thin copolymer films could be processed as resists but that films greater than 3000 Å thick cracked in the solvents used to dissolve the radiation-exposed regions. Incorporation of plasticizing additives did not improve the film properties. Films from low molecular weight polymer fractions cracked less in solvents, but higher radiation doses were required to offset the reduced sensitivity. This resulted in the formation of intractable residues in the exposed regions which appear to be crosslinked polymer. Bicycloheptene monomers with specific functional groups did not improve the properties of the copolymer films. Terpolymerization with α-olefins such as butene-1 and cis-2-butene plasticized these films and reduced their tendency to crack in solvents. Poly(cyclopentene sulfone–co–butene-1 sulfone) films were found to have the best properties, and 1.25-μ resist images could be etched in SiO₂ layers at an exposure dose of 4 × 10^?6 C/cm² at 25KV. However, one important limitation of this terpolymer was the low dissolution rate ratio between the exposed and unexposed regions. Since straight-walled relief images are essential to the formation of high-resolution patterns, the usefulness of this terpolymer as an electron beam resist appears to be hindered by the limited choice of good solvents to maximize the dissolution rate ratio. PBCHS block terpolymers containing methyl methacrylate (MMA) or methacrylic acid (MAA) were synthesized to improve the solubility in solvents and to incorporate the properties of methacrylates. PBCHS–MMA films cracked in solvents after irradiation; PBCHS–MAA polymers were too insoluble to form resist films.     

Thermal behavior and specific interaction in high glass transition temperature PMMA copolymer

A series of high glass transition temperature copolymers based on poly(methyl methacrylate) (PMMA) were prepared by free radical copolymerization of methacrylamide and methyl methacrylate monomers in dioxane solvent. The thermal properties and hydrogen-bonding interactions of these poly(methacrylamide-co-methyl methacrylate) (PMAAM-co-PMMA) copolymers with various compositions were investigated by differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and solid-state nuclear magnetic resonance (NMR) spectroscopy. A large positive deviation in the behavior of T_g, based on the Kwei equation from DSC analyses, indicates that strong hydrogen bonding exists between these two monomer segments. The FTIR and solid-state NMR spectroscopic analyses give positive evidence for the hydrogen-bonding interaction between the carbonyl group of PMMA and the amide group of PMAAM (e.g. by displaying significant changes in chemical shifts). Furthermore, the proton spin-lattice relaxation time in the rotating frame (T_1ρ(H)) has one single value over the entire range of compositions of copolymers, and gives a value shorter than the average predicted. The proton relaxation behavior indicates the rigid nature of the copolymer.     

Synthesis of poly(styrene-co-maleimide) and poly(octadecene-co-maleimide) nanoparticles and their utilization in paper coating

Aqueous polymer dispersions comprising of poly(styrene-co-maleimide) (SMI) or poly(octadecene-co-maleimide) (OMI) nanoparticles were synthesized by thermal imidization of the corresponding maleic anhydride copolymer precursors with ammonia using an organic solvent free process. Different reaction parameters such as temperature, time, agitation speed and stirrer geometry, and molar ratio of ammonia-to-anhydride were investigated in order to find optimal conditions. The obtained copolymer nanoparticles exhibited glass transition temperatures (T_g's) between 140 and 170 °C with particle sizes ranging from 50 to 230 nm. The compositional analysis was conducted by recording ¹H NMR and ATR-FTIR spectra. In addition, SMI dispersions were successfully spray dried and analyzed by SEM. Finally, the polymer dispersion's utility as auxiliary organic pigment in paper coating formulations was evaluated.     

A comparative study on corrosion-resistant performance of halogenated copolymers

Methacrylate-based copolymers are frequently used as anticorrosive organic coatings. Polymeric coating on metallic surfaces provides protection by a barrier action. Thermal properties have a significant influence on corrosion-resistance. This paper deals with the effect of thermal properties of 2,4,6-tribromophenyl methacrylate-co-glycidyl methacrylate and N-(p-bromophenyl)-2-methacrylamide-co-glycidyl methacrylate copolymers in corrosion-resistant behavior on low nickel stainless steel (LNSS). Hence attempts have been made to synthesize a set of copolymers by free radical polymerization and compare their corrosion-resistance properties. The copolymers were structurally characterized by Fourier transform-infrared, and ¹H-nuclear magnetic resonance spectroscopic techniques. The molecular weight of the copolymers was determined by gel permeation chromatography. Thermal studies were carried out using thermogravimetric analysis and differential scanning calorimetry. Corrosion performances of LNSS coated with two different copolymers was investigated in 1 M H₂SO₄ using potentiodynamic polarization and electrochemical impedance spectroscopic methods. The corrosion study reveals that poly(TBPMA-co-GMA) showed better corrosion-resistance than poly(PBPMA-co-GMA).     

The synthesis and characterization of functional poly(citraconic anhydride-co-styrene-co-vinylphosphonic acid)s

New functional terpolymers of citraconic anhydride (CA), styrene (S) and vinylphosphonic acid (VPA) were synthesized at different compositions by complex-radical ternary polymerization. Studied ternary acceptor-donor-acceptor system was described as a binary copolymerization of two monomer complexes of CA…S (1) and VPA…S (2). The monomer reactivity ratios of these complexes were determined by ¹H NMR analysis for monomer mixtures before and after reactions by modified Jaacks equations: r_I = r₁(K_c1/K_c2) = 1.99, r_II = r₂(K_c2/K_c1) = 0.16; r₁ = 18.59, r₂ = 0.018 (taking into account K_c for the corresponding monomer complexes). Copolymerization constants verify the fact that complexed monomer pairs have a tendency towards random copolymerization. Monomer unit compositions and characterizations of a series of poly(CA-co-S-co-VPA)s were investigated by FTIR, Raman, ¹H NMR, ¹³C NMR, DEPT-135, ³¹P NMR, GPC and thermal properties were investigated by TGA and DSC methods. Molecular weight and thermal stability increased with increasing VPA content in terpolymer. Dynamic mechanical properties were investigated by DMA and all terpolymers show typical viscoelastic behavior of an amorphous polymer. Solution properties were also studied by viscometry and titration.