Synthesis Of Copolymers Research Articles

Synthesis and thermal behavior of RAFT-based copolymers of acrylonitrile and 1-vinylimidazole

The copolymers of acrylonitrile and 1-vinylimidazole with a narrow molecular weight distribution (MWD) were synthesized for the first time by the reversible addition–fragmentation chain transfer (RAFT) polymerization in a DMSO solution in the presence of acetic acid. Their thermal behavior difference upon heating in argon and in air along with ability to melt make them promising precursors for carbon fiber production.

Preparation and characterization of chemically and electrochemically synthesized 3,4-ethylenedioxy pyrrole/pyrrole (EDOP/Py) copolymers

Abstract In this study, 3,4-ethylenedioxypyrrole (EDOP) and pyrrole (Py) copolymers were prepared by chemical and electrochemical polymerization methods. The properties of the polymers obtained by both methods were compared. Chemical synthesis of copolymers was carried out with ferric chloride (FeCl3) in the acetonitrile (ACN) environment. The electrochemical synthesis was carried out with lithium perchlorate (LiClO4) electrolyte and suitable oxidation potential range in ACN solution. The properties of polypyrrole (PPy) copolymers were performed with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and conductivity measurements. Depending on the polymerization method and pyrrole amount in copolymer, thermal stability, conductivity and surface morphology were varied.

Dual pH- and Thermo-Sensitive Poly(N-isopropylacrylamide-co-allylamine) Nanogels for Curcumin Delivery: Swelling-Deswelling Behavior and Phase Transition Mechanism.

Curcumin (Cur) is a beneficial ingredient with numerous bioactivities. However, due to its low solubility and poor bioavailability, its therapeutic application is limited. In this work, we prepared poly-N-isopropylacrylamide p(NIPAm) and polyallylamine p(Am)-based nanogel (p(NIPAm-co-Am)) NG for a dual pH- and temperature-sensitive copolymer system for drug delivery application. In this copolymer system, the p(NIPAm) segment was incorporated to introduce thermoresponsive behavior and the p(Am) segment was incorporated to introduce drug binding sites (amine groups) in the resulting (p(NIPAm-co-Am)) NG system. Various instrumental characterizations including 1H nuclear magnetic resonance (1H NMR) spectroscopy, Fourier transform infrared (FT-IR) analysis, scanning electron microscopy (SEM), zeta potential, and particle size analysis were performed to confirm the copolymer synthesis. Curcumin (Cur), an anticancer bioactive substance, was employed to assess the in vitro drug loading and release performance of the resulting copolymer nanogels system at varied pH levels (pH 7.2, 6.5, and 4.0) and temperatures (25 °C, 37 °C, and 42 °C). The cytocompatibility of the p(NIPAm-co-Am) NG sample was also tested on MDA-MB-231 cells at various sample concentrations. All the study results indicate that the p(NIPAm-co-Am) NG produced might be effective for drug loading and release under pH and temperature dual-stimuli conditions. As a result, the p(NIPAm-co-Am) NG system has the potential to be beneficial in the use of drug delivery applications in cancer therapy.

Synthesis of Polyethylene Glycol-Poly(glycerol carbonate) Block Copolymeric Micelles as Surfactant-Free Drug Delivery Systems.

We report the synthesis of block copolymers of monomethoxylated polyethylene glycol and poly(glycerol carbonate) (mPEG-b-PGC) via the ring-opening polymerization of benzyl glycidyl ether, monomethoxylated polyethylene glycol, and carbon dioxide using a cobalt salen catalyst. The resulting block copolymers display high polymer/cyclic carbonate selectivity (>99%) and, if two oxirane monomers are used, random incorporation into the polymer feed. The resulting diblock mPEG-b-PGC polymer shows promise as a nanocarrier for surfactant-free, sustained chemotherapeutic delivery. mPEG-b-PGC, with paclitaxel conjugated to the pendant primary alcohol of the glycerol polymer backbone, readily forms 175 nm diameter particles in solution and contains 4.6 wt % paclitaxel (PTX), which is released over 42 days. The mPEG-b-PGC polymer itself is noncytotoxic, whereas the PTX-loaded nanoparticles are cytotoxic to lung, breast, and ovarian cancer cell lines.

Using Catechol and Zwitterion-Functionalized Copolymers to Prevent Dental Bacterial Adhesion.

In this manuscript, we report the synthesis of zwitterionic copolymers and their ability to form antifouling coatings on porous hydroxyapatite as a mimic of dental coatings. Specifically, we systematically investigated how altering the composition of copolymers of catechol methacrylate (Cat-MA or 2) and methacryloyloxyethyl phosphorylcholine (2-MPC) with varying catechol-to-zwitterion ratios impacted their adhesive and antifouling properties, allowing for the rational design of functional coatings. Characterization by ellipsometry, contact angle goniometry, and X-ray photoelectron spectroscopy revealed the presence of hydrophilic copolymer coatings of ∼10 nm thickness. Notably, these copolymers adhered to hydroxyapatite and reduced the level of attachment of both Gram-negative Escherichia coli and Gram-positive Streptococcus oralis. Additionally, in vitro experiments that mimicked the complex mouth environment (i.e., swallowing and using mouthwash) were employed to evaluate S. oralis adhesion, finding that the copolymer coatings reduced the quantity of adhered bacteria. We suggest that these copolymers provide insights into the design of antifouling coatings that are appropriate for use in oral care.

Synthesis, characterization, and luminescent properties of copolymer based on derivatives of 1,2,4-triazole containing Eu(III) and Tb(III) emitters

New Eu(III) and Tb(III) hybrid materials based on N-((1-methyl-3-(pyridin-2-yl)-1H-1,2,4-triazol-5-yl)methyl)methacrylamide were synthesized and characterized as potential fluorescent emitters. Complexes of Eu(III) and Tb(III) demonstrate red and green luminescence in the visible region, respectively. The intense broad bands in the region of 270–290 nm are related to electronic transitions within pyridine-triazole-containing fragment coordinated to Ln(III) ion.

Synthesis and characterization of a brush type graft copolymer via RAFT and "click" chemistry methods

Synthesis and characterization of a brush type graft copolymer via RAFT and "click" chemistry methods

Exploring the impact of process parameters on the metal-free light-catalyzed ATRP polymerization of PVDF-based block copolymers

The synthesis of well-defined poly(vinylidene fluoride) (PVDF)-based block copolymers has been an important topic in recent years to accurately modify its properties and to achieve high-quality composites. Atom transfer radical polymerization (ATRP) proved itself to be a viable technique for the controlled synthesis of PVDF-based block copolymers. Recently, organic photoredox catalysts (OPRCs) have been reported as effective photocatalysts in light-catalyzed ATRP. Here, we use three OPRs (perylene, 10-methylphenotiazine, 10-phenylphenotiazine) for the ATRP of methylmethacrylate using telechelic PVDF as macroinitiators. We explore the impact of three process parameters: the end group on the polymer chain, the concentration of MMA, and the concentration of the OPRC in solution. First, three different telechelic PVDF were tested under the same monomer and OPRC concentrations to select the best macroinitiator for this system. Then, the effects on the overall control and on the conversion when the concentration of monomer or OPRC is varied were evaluated.

Synthesis and Characterization of Electro-Optic Polyurethaneimide-Polyimide Copolymers

Polyurethaneimide prepolymer was synthesized using the synthesized chromophore C containing tricyanofuran, hexafluorodianhydride and phenyl diisocyanate as monomers. Polyimide prepolymers were synthesized using fluorinated aromatic diether dianhydride and fluorinated aromatic diamine as monomers. Polyurethaneimide-polyimide (PUI-FPI) copolymers were then synthesized by a polycondensation reaction of the polyimide and polyurethaneimide prepolymers. The electro-optic (EO) PUI-FPI copolymers had a special segment structure and concentrate the advantages of polyurethaneimide and polyimide. The copolymers exhibited good film-forming properties, high glass transition temperature (Tg =196 °C), and high thermal stability (Td up to 358 °C). The copolymers possessed a high EO coefficient (γ33 =72 pm/V) at the 1550 nm wavelength, good long-term electro-poled orientation stability, and low optical propagation loss (1.2–1.4 dB/cm) at 1550 nm. Mach-Zehnder interferometric electro-optic modulators were designed and fabricated using the synthesized copolymer as the waveguide material. The prepared polymer optical waveguide EO modulators showed a good low-frequency electro-optic modulation response. The results showed that the synthesized polyurethaneimide-polyimide copolymers meeted the performance requirements for the preparation of polymeric optical waveguide devices and were suitable as polymeric electro-optic waveguide materials.

Synthesis and evaluation of multi-aromatic ring copolymer as viscosity reducer for enhancing heavy oil recovery

Functional polymers play an increasingly significant role in oilfield development. Herein, the side-chain functionalized copolymer APVR was fabricated using functional monomer 2,6-bis(1-methyl-1H-benzo[d]imidazol-2-yl)pyridin-4-yl-methacrylate (BMP) with similar structure to the heavy components in crude oil and di-hexadecanol maleate (DHM) with long alkyl chain. 1H NMR, FTIR and TGA analyses were employed to characterize the structure of APVR. Simultaneously, viscosity reduction performance and heavy oil displacement performance of APVR were also studied. For comparison, the copolymers P(AAB), P(AAD) and P(AA) containing one functional monomer and without functional monomer were also synthesized. The results showed that when the copolymer concentration is 2000 mg/L, the viscosity reduction rate (VRR) of APVR, P(AAB), P(AAD) and P(AA) is 93.1%, 84.3%, 82.4% and 65.4%, respectively. Furthermore, compared with water flooding, their ultimate recovery of heavy oil increased by 18.34%, 13.78%, 13.18% and 9.93%. The interaction mechanisms between APVR and heavy oil were studied using XRD, SEM, and molecular dynamic simulation. Due to their unique structure, BMP and DHM were able to permeate into the molecule structures of heavy oil, reducing the intermolecular forces between heavy components by forming supramolecular forces with asphaltene. Thus, they led to the loose stacking of asphaltene aggregates, making it easier for APVR to emulsify oil droplets due to its amphiphilic property. The copolymer APVR shows promising potential for reducing heavy oil viscosity and may have broad application prospects in heavy oil exploitation.

Highly Sensitive Detection of Bacteria by Binder-Coupled Multifunctional Polymeric Dyes.

Infectious diseases caused by pathogens are a health burden, but traditional pathogen identification methods are complex and time-consuming. In this work, we have developed well-defined, multifunctional copolymers with rhodamine B dye synthesized by atom transfer radical polymerization (ATRP) using fully oxygen-tolerant photoredox/copper dual catalysis. ATRP enabled the efficient synthesis of copolymers with multiple fluorescent dyes from a biotin-functionalized initiator. Biotinylated dye copolymers were conjugated to antibody (Ab) or cell-wall binding domain (CBD), resulting in a highly fluorescent polymeric dye-binder complex. We showed that the unique combination of multifunctional polymeric dyes and strain-specific Ab or CBD exhibited both enhanced fluorescence and target selectivity for bioimaging of Staphylococcus aureus by flow cytometry and confocal microscopy. The ATRP-derived polymeric dyes have the potential as biosensors for the detection of target DNA, protein, or bacteria, as well as bioimaging.

ENERGY- AND RESOURCE-SAVING PROCESSES INVOLVING THE POLYMER PHASE

The paper deals with the processes of application and production of various polymer materials. By coating the surface of mineral fertilizer granules with hydrophobic polymer films, fertilizers with controlled release of nutrient components were obtained. Such fertilizers can prevent the leaching of nutrients, prevent the negative impact on the environment and reduce fertilizer consumption. Methods for calculating the particle distribution function by the degree of coating characterizing the uniformity of coating on fluidized bed particles for stationary and non-stationary modes of operation of the apparatus are considered. The process of applying a thick composite coating to the surface of urea granules in a pan granulator was also investigated. A simple method for calculating the size distribution of the obtained granules with a composite shell is proposed. The actual problem of developing a method for predicting the kinetics of nutrient release from polymer-coated fertilizer granules based on a fairly simple mathematical model of the process has been solved. Studies of the combined polymerization and drying process in the synthesis of polyacrylamide and sodium methacrylate copolymer with methacrylic acid amide have shown that its use at the final stage of obtaining water-soluble acrylic polymers is very effective. This technique allows to reduce the total time of the technological cycle. The process of obtaining polyethylene powder by the method of elastic-deformation grinding of polymer gel and a two-stage process of solvent removal from polymer powder with the return of the solvent to the technological cycle has been developed. The rational technological parameters of the electrodialysis process of contaminated steam condensate of mineral fertilizers plant have been identified, which allows to obtain a more concentrated salt solution, which is used as a secondary raw material, as well as a desalinated solution used as process water. For citation: Lipin A.G., Lipin A.A. Energy- and resource-saving processes involving the polymer phase. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 7. P. 203-213. DOI: 10.6060/ivkkt.20236607. 6836j.

Microflow system for controlled synthesis of ethylene-vinyl acetate copolymers: Continuous copolymerization and kinetic study

Ethylene content in ethylene–vinyl acetate copolymers (EVA) is a key factor that determines its further usage. While conventional batch reactor for EVA synthesis faces the problem of heterogeneous reaction environment and temperature control. A microflow system was designed to avoid these problems and facilitate the synthesis of EVA with controlled ethylene content. Continuous flow synthesis of EVA by solution free radical copolymerization was realized homogeneously based on this microflow system. 13C NMR spectra indicate that EVA obtained in microflow system has less ethylene concentrated sequence than EVA obtained in batch reactor. By operating the microflow system in a stop-flow method, we developed a simple kinetic model of copolymerization and measured the reactivity ratios of ethylene and vinyl acetate copolymerization in tert-butyl alcohol and dimethyl carbonate. The microflow system is demonstrated to be a powerful tool in kinetic and mechanism study and engineering application of copolymerization processes involving monomers which are gas phase under conventional condition.

Synthesis and characterization of PANI and PANI-indole copolymer and study of their antimalarial and antituberculosis activity.

The preparation of polyaniline (PANI) and its copolymer with indole involved a chemical oxidative polymerization method, with benzene sulfonic acid (BSA, C6H6O3S) used as a dopant and potassium persulfate (PPS, K2S2O8) as an oxidant. The synthesized compounds underwent characterization using FTIR, 1H-NMR, TGA, and GPC techniques, which allowed the calculation of their average molecular weight and polydispersity index (PDI) through the GPC technique. The PDI values of the PANI copolymer with indole in different aniline-to-indole ratios were 1.53, 1.13, and 1.532 for 1:1, 1:2, and 2:1 ratios, respectively. Thermal stability was determined using TGA, revealing that the indole heterocyclic compound increased the inflexibility of the polymer chains in the synthesized PANI copolymer. The structure of the copolymer was further analyzed using 1HNMR and FTIR techniques, which confirmed the existence of benzenoid and quinoid groups in the PANI-indole copolymers, as well as the effect of doping on the polymer chains. The antibacterial and antifungal properties of the copolymers were studied against several bacterial and fungal strains and measured in terms of minimum inhibitory concentration. Results indicated that the inhibition rate of the PANI-indole copolymer on S. pyogenus (MTCC 442) was higher than that of standard drugs and individual PANI. The PANI-indole copolymers also displayed excellent antituberculosis and antimalarial activities, with the synthesized copolymer showing better outcomes than individual PANI.

Toughening of Bio-Based PA6.19 by Copolymerization with PA 6.6 - Synthesis and Production of Melt-Spun Monofilaments and Knitted Fabrics.

This work reports on the synthesis of statistical copolymers of bio-based PA6.19 and PA6.6 together with the production of melt-spun monofilaments for the production of sustainable textile fibers. The plant oil-based 1.19-nonadecanedioic acid is synthesized from bio-derived oleic acid via isomerizing methoxycarbonylation. The homopolymer PA6.19 with a carbon-based bio-content of 72% showsa good elongation at break of 166%, but lower tensile strength than commercial PA6 (43MPa versus 82MPa). Addition of adipic acid to form statistical PA 6.6/6.19 copolymers improves toughness while maintaining the high elongation at break. Two PA6.6/6.19 copolymers with a carbon-based bio-content of 26% and 33% are successfully synthesized and exhibited comparable toughness (94 ± 6MPa and 92 ± 2MPa) to the commercial PA6 (92 ± 15MPa). The bio-based copolymers also exhibit a much lower water uptake than PA 6 and PA 6.6, resulting in a higher dimensional stability. Melt spinning of the oleic acid-based polyamides is successfully carried out to produce monofilaments with sufficient properties for further processing in a knitting process, demonstrating the capabilities of the bio-based PA6.6/6.19 copolymers for use in the textile industry.

Synthesis and Molecular-Hydrodynamic Characteristics of Comb-Shaped Random Copolymers of N-Methyl-N-vinylacetamide and N-Methyl-N-vinylamine with Dodecyl Side Groups

Synthesis and Molecular-Hydrodynamic Characteristics of Comb-Shaped Random Copolymers of N-Methyl-N-vinylacetamide and N-Methyl-N-vinylamine with Dodecyl Side Groups

Nonstoichiometric Migita-Kosugi-Stille Coupling Polycondensation based on Intramolecular Catalyst Transfer System

In this paper, a nonstoichiometric Migita-Kosugi-Stille coupling polycondensation based on intramolecular catalyst transfer systems has been reviewed. The achievement of those systems is significant from the viewpoints of (1) acquisition of new knowledge in the synthesis of semiconducting polymer materials, (2) unnecessary strict control in monomer feed ratios generally required for a single-phased solution polycondensation, (3) possible improvement of the monomer reactivity by varying feed ratios, and (4) possibility of controlled chain end groups and extension to the synthesis of all-conjugated block copolymers. In practice, naphthalene-diimide-, phthalimide-, and terephthalate-based π-conjugated polymers have been synthesized under imbalanced stoichiometric conditions, possessing much higher molecular weights than those based on Carothers/Flory’s theory. The results of various model reactions and DFT calculations have revealed that the origin of the intramolecular catalyst transfer phenomenon is related to the existence of carbonyl groups introduced at the ortho-position of dibromo aryl monomers used in excess as well as types of palladium catalysts/precatalysts. In the near future, the proposed nonstoichiometric Migita-Kosugi-Stille coupling polycondensation will be established by extending the adaptable monomers and further optimizing catalysts/precatalysts.

Synthesis of Multiblock Copolymer Composed of Biodegradable Poly(butylene succinate) and Poly(2-pyrrolidone): Impact of Each Block Length on the Mechanical Properties.

A series of multiblock copolymers comprising a systematic combination of biomass-originated and biodegradable poly(butylene succinate) (PBS) and poly(2-pyrrolidone) (PA4) units is synthesized with various mean degrees of polymerization (mDP) of each unit. Despite the inherent immiscibility of PBS and PA4, multiblock structure allows to mix the two components in the solution-cast films from solution. The mechanical properties of the cast films are highly dependent on the mDP of each unit, as demonstrated by tensile tests. The film of the copolymer with the lowest mDP of each unit (PBS: 17, PA4: 10) is transparent and exhibits extremely high elongation at break (> 400%) and high tensile stress (39.5MPa) with strain hardening. The films with 50% or higher crystallinity are brittle and opaque, while a decrease in crystallinity can result in higher elongation, as revealed by wide-angle X-ray diffraction measurements.

In Situ Monitoring of Polymerization-Induced Self-Assembly and Gelation During the Synthesis of Triblock Copolymers via Time-Resolved Small-Angle X-ray Scattering and Rheology

<i>In Situ</i> Monitoring of Polymerization-Induced Self-Assembly and Gelation During the Synthesis of Triblock Copolymers <i>via</i> Time-Resolved Small-Angle X-ray Scattering and Rheology

Synthesis of sulfur-containing polycarbonate block copolymers via Salen-metal catalyzed copolymerization of CO2, propylene oxide, and phthalic thioanhydride

Sulfur-containing ABA-type polycarbonate triblock copolymers were synthesized via sequential copolymerization of propylene oxide (PO) and carbon dioxide (CO2), followed by propylene oxide (PO) and phthalic thioanhydride (PTA) in the presence of water and Salen-Metal catalysts. The reaction was catalyzed using Salen-Co(III)-Cl/[PPN]Cl and Salen-Cr(III)-Cl/[PPN]Cl catalyst systems. The content of thioester units in the copolymer chain could be adjusted by varying the feed ratios of PTA. These triblock polymers displayed a higher refractive index, reaching up to 1.561.