Types Of Copolymers Research Articles

Bay-substituted perylene diimide-based donor–acceptor type copolymers: design, synthesis, optical and energy storage behaviours

Four bay-substituted perylene diimide (PDI) copolymers have been designed and synthesized successfully to demonstrate the effect of bay-substituent on the photo-physical and capacitive properties.

Corrigendum to “Fluorinated phenanthrenequinoxaline-based D-A type copolymers for non-fullerene polymer solar cells” [Polymer 250 (2022) 124867

Corrigendum to “Fluorinated phenanthrenequinoxaline-based D-A type copolymers for non-fullerene polymer solar cells” [Polymer 250 (2022) 124867

Fluorescent sensing copolymers: Synthesis, nanofiber fabrication and application in picric acid sensors

Increasing attention has been paid to the detection of explosives due to the occurrence of terrorist attacks around the world. Here, we used free radical polymerization to develop two different types of fluorescent copolymers for use in detecting picric acid. One exhibits aggregation-caused quenching (ACQ) and is called PNNS [poly (N-isopropyl acrylamide-co-N-hydroxymethyl acrylamide -co-styrene-pyrene), poly (NIPAAm-co-NMA-co-St-Py)]. The other possesses aggregation-induced emission (AIE) properties and is called PNNP [poly (N-isopropyl acrylamide-co-N-hydroxymethyl acrylamide-co-2-(1,2,3,4,5-pentaphenyl-1H-silol-1-yloxy) ethyl methacrylate), poly (NIPAAm-co-NMA-co-PPS-HEMA)]. Nanofibrous thin films of these copolymers were obtained by electrospinning. Upon interaction with picric acid, the fluorescence intensity of each copolymer was quenched due to photo-induced electron transfer (PET). The average diameters of PNNS and PNNP nanofibers were 179 ± 28 nm and 235 ± 143 nm, respectively. Sensing performance was evaluated by Stern-Volmer analysis. The Stern-Volmer constant (Ksv) values for PNNS and PNNP nanofibers were 0.012 μΜ−1 and 0.119 μΜ−1, respectively. Since the aggregated state of PNNP nanofibrous thin films can increase dramatically, the AIE property of this material provides a large dynamic range. Finally, the reusability of water- and methanol-washed nanofiber thin films was tested, revealing that the nanofiber sensors were reusable for detecting picric acid.

Synthesis and Evaluation of Polyphenylene-Based Copolymers with Superacid Groups (IV)-Effect of Superacid Structure

In order to improve the performance of polymer electrolyte fuel cells (PEFCs), polyelectrolytes with higher proton conductivity under low humidity and high temperature conditions will be required. It is well known that hydrocarbon polyelectrolytes with superacid groups show high proton conductivity at low relative humidity (RH) conditions compared to typical sulfonated polyelectrolytes due to the strong acidity providing a high efficiency of carrier generation. In this study, random copolymers consisting of the hydrophilic poly(4’-phenoxybenzoyl-1,4-phenylene) (SNF-PPBP) unit with sulfonyl(trifluoromethyl sulfonyl)imidate as a super acid group, and the hydrophobic poly(benzoyl-1,4-phenylene) (PBP) unit were synthesized. The effect of the hydrophilic structure and phase separation on electrolyte membrane properties was investigated. Two types of random copolymers, PPBP m -PBP n with different copolymerization ratios (m : n) were synthesized by Ni(0) coupling reaction. The copolymerization ratios of PPBP m -PBP n were 1.2 : 1.0 and 2.3 : 1.0, respectively. The number-average molecular weights were determined by GPC to be 2.22×104 g mol-1 (PPBP1.2-PBP1.0) and 3.03×104 g mol-1 (PPBP2.3-PBP1.0), respectively. After chlorosulfonation of PPBP m -PBP n s (SC-PPBP-PBPs), trifluoromethyl-bis(sulfonyl)imide (SNF) groups were introduced by using trifluoromethansulfonamide. FT-IR measurements suggested that the sulfonate groups were also introduced as by-products during the synthesis of SC-PPBP-PBP. The introduction rate of sulfonyl chloride groups (X SC) and sulfonate groups (X SO3H) to PPBP units of SC-PPBP-PBP and that of SNF groups (Y SNF) and sulfonate groups (Y SO3H) were estimated from elemental analysis data. The X SC and X SO3H for PPBP units of SC-PPBP-PBPs were 75% and 62% (SC-PPBP1.2-PBP1.0), and 61% and 51% (SC-PPBP2.3-PBP1.0), respectively. The Y SNF and Y SO3H for PPBP units of SNF-PPBP-PBPs were 75% and 62% (SNF-PPBP1.2-PBP1.0), and 62% and 50% (SNF-PPBP2.3-PBP1.0). The ion exchange capacity (IEC) of SNF-PPBP-PBPs determined by back titration was 2.41 meq g-1 (SNF-PPBP1.2-PBP1.0) and 2.23 meq g-1 (SNF-PPBP2.3-PBP1.0). TG-MS measurements exhibit that the 5% weight loss temperature (T d-5%) of both polymers was about 230℃, indicating that both polymers have sufficient thermal resistance for PEFC applications. Despite the high IEC value, SNF-PPBP1.2-PBP1.0 showed higher thermal resistance because of the dense introduction of ion exchange groups and these electron-withdrawing properties. The proton conductivity was evaluated in the range of 30 - 80%RH at 80oC, and SNF-PPBP-PBPs showed higher humidity dependence and proton conductivity compared with Nafion®211 membrane under high humidification conditions. SNF-PPBP-PBPs also showed higher proton conductivity than that of the homopolymer SNF-PPBP (IEC = 2.39 meq g-1). These results suggest that the superacid groups have high carrier generation ability, especially in high humidity regions, and the random copolymer structure contributes to the improvement of proton conduction. The PEFC performance was evaluated at 80oC and 90%RH using membrane assembly electrodes (MEAs) fabricated with SNF-PPBP-PBPs, Nafion®211, and SNF-PPBP (IEC = 2.51 meq g-1) membranes. The limiting current densities (I lim) of MEAs with SNF- PPBP1.2-PBP1.0, SNF-PPBP2.3-PBP1.0, Nafion®211, and SNF-PPBP membranes were 1825, 1904, 1924, and 1429 mA cm-2, respectively. The membrane resistance (R m) of MEAs with SNF- PPBP1.2-PBP1.0, SNF-PPBP2.3-PBP1.0, and Nafion®211 membranes were 29, 17, and 21 mΩ, respectively. SNF-PPBP1.2-PBP1.0 and SNF-PPBP2.3-PBP1.0 MEAs showed high power generation properties comparable to Nafion MEAs regardless of the copolymerization ratio.

Tailoring copolymer architectures and macromolecular interactions for enhanced nanotherapeutic delivery: A design-by-architecture approach

Amphiphilic copolymers with precise macromolecular topologies are crucial in nanomedicine for enhancing drug delivery by improving solubilization, stabilization, and therapeutic efficacy on target tissues. This study employs a design-by-architecture approach to identify factors influencing interactions between synthesized macromolecules and biological systems for optimal drug nanodelivery. Copolymers combining poly(ε-caprolactone) blocks and poly(polyethylene glycol methacrylate) or poly(glycerol methacrylate), were synthesized to investigate how architectural adjustments impact self-assembly, nanoparticle size, drug loading, and biomolecule interactions. Linear and brush block copolymers with varied block lengths were studied for their self-assembly behavior in aqueous environments. Both copolymer types formed smaller nanoparticles with extended hydrophilic blocks, with brush block copolymers showing superior performance due to their peculiar macromolecular architecture. Incorporating ‘clickable’ glycidyl units within the hydrophilic block minimally affected particle size. Controlled functionalization with thiol groups resulted in stable nanoparticles with enhanced size reduction and mucoadhesive properties, potentially improving targeted drug delivery and therapeutic effects.

Hydrophobically associated amphiphilic copolymer fracturing fluid with dual Functions of fracturing and flooding for enhanced oil recovery

Polymer fracturing fluids are widely used in oil and gas extraction; however, the residues left after gel breaking can easily clog fractures, leading to formation damage and a decline in economic benefits. To address this issue, this study developed a new type of hydrophobic associative amphiphilic copolymer, P(AM-AA-AAEOn), prepared through the copolymerization of fatty alcohol polyoxyethylene ether (AAEOn), acrylic acid, and acrylamide. The properties of the system, including shear resistance and thixotropy, shear recovery, viscoelasticity, salt responsiveness, and interfacial tension, were thoroughly investigated by measuring its hydrodynamic size, molecular weight, root-mean-square radius of gyration, and second virial coefficient. Experimental results demonstrated that with a monomer ratio of 300:100:1, this fracturing fluid system exhibited excellent shear resistance, viscoelasticity, effective sand carrying, and corrosion inhibition, along with good gel-breaking and compatibility properties. Further oil displacement tests revealed that P(AM-AA-AAEOn), due to its superior interfacial activity and wettability, significantly enhanced oil recovery efficiency by 25.01%. These characteristics not only resolved the issue of flowback in traditional polymer fracturing fluids but also facilitated the efficient integration of fracturing and oil displacement. The innovation of this research lies in the development of a novel, efficient, and environmentally friendly fracturing fluid, which provides significant theoretical and practical foundations for oilfield fracturing technology and holds promising industrial application prospects.

The Effect of Hydrophobic Modified Block Copolymers on Water-Oil Interfacial Properties and the Demulsification of Crude Oil Emulsions.

The demulsification effect of three types of block copolymers, BP123, BPF123, and H123, with the same PEO and PPO segments but different hydrophobic modification groups on crude oil emulsions and the properties of oil-water interfaces were investigated using demulsification experiments, an interfacial tensiometer, and surface viscoelastic and zeta potential instruments in this paper. The results showed that the hydrophobic modification group of the block copolymers had great effects on the demulsification performance. The H123 block copolymers with the strongest hydrophobicity had the best demulsification effect on the crude oil emulsions. The properties of the oil-water interfaces indicated that the modified block copolymers achieved the demulsification of crude oil emulsions by reducing the strength of the oil-water interfacial film and the interfacial tension.

Visible-Light-Induced Diselenide-Crosslinked Polymeric Micelles for ROS-Triggered Drug Delivery.

To synthesize an effective and versatile nano-platform serving as a promising carrier for controlled drug delivery, visible-light-induced diselenide-crosslinked polyurethane micelles were designed and prepared for ROS-triggered on-demand doxorubicin (DOX) release. A rationally designed amphiphilic block copolymer, poly(ethylene glycol)-b-poly(diselenolane diol-co-isophorone diisocyanate)-b-poly(ethylene glycol) (PEG-b-PUSe-b-PEG), which incorporates dangling diselenolane groups within the hydrophobic PU segments, was initially synthesized through the polycondensation reaction. In aqueous media, this type of amphiphilic block copolymer can self-assemble into micellar aggregates and encapsulate DOX within the micellar core, forming DOX-loaded micelles that are subsequently in situ core-crosslinked by diselenides via a visible-light-triggered metathesis reaction of Se-Se bonds. Compared with the non-crosslinked micelles (NCLMs), the as-prepared diselenide-crosslinked micelles (CLMs) exhibited a smaller particle size and improved colloidal stability. In vitro release studies have demonstrated suppressed drug release behavior for CLMs in physiological conditions, as compared to the NCLMs, whereas a burst release of DOX occurred upon exposure to an oxidation environment. Moreover, MTT assay results have revealed that the crosslinked polyurethane micelles displayed no significant cytotoxicity towards HeLa cells. Cellular uptake analyses have suggested the effective internalization of DOX-loaded crosslinked micelles and DOX release within cancer cells. These findings suggest that this kind of ROS-triggered reversibly crosslinked polyurethane micelles hold significant potential as a ROS-responsive drug delivery system.

Effect of ionic liquids on the polymerization behavior of acrylamide‐based copolymers

AbstractTo explore the influence of reaction medium on the copolymerization behavior of acrylamide‐based copolymers, three types of copolymers (P(AM‐St)(ILs), P(AM‐MMA)(ILs), and P(AM‐AMPS)(ILs)) were synthesized by combining insoluble, slightly soluble, and easily soluble monomers with acrylamide in the 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([BMIM]BF4) reaction medium. The reactivity ratio, Fourier transform infrared spectroscopy, 1H NMR spectroscopy, elemental analysis, and scanning electron microscopy were employed to characterize the copolymers' properties. The results indicated that in [BMIM]BF4 copolymerization, the reactivity ratio of AM and St in P(AM‐St)(ILs) decreased, the reactivity ratio of AM in P(AM‐MMA)(ILs) will increase. While the reactivity ratio of MMA will decrease. The reactivity ratio of AM in P(AM‐AMPS)(ILs) will increase and the reactivity ratio of AMPS will decrease. The distribution of AM and St segments in P(AM‐St)(ILs) molecular chains is more uniform and compact. When AM polymerizes with hydrophobic monomers (St) in [BMIM]BF4, its copolymer solution exhibits lower viscosity loss rates in temperature, shear, and salt resistance tests. Therefore, ionic liquids are more suitable as reaction media for the synthesis of hydrophobic‐modified polyacrylamides, which facilitate a more uniform distribution of hydrophobic monomers within the copolymer chains and exhibit enhanced resistance to temperature, salt, and shear stresses.

Polymeric Micelles in Colorectal Cancer Therapy: A Comprehensive Review of Nano-drug Delivery Strategies, Copolymer Types, Physicochemical Characteristics, and Therapeutic Applications.

Polymeric micelles are becoming the method of choice for a nano-drug delivery system, especially in colorectal cancer treatment. These tiny structures have become popular for their amazing qualities that make drug delivery more efficient and therapies better. Colorectal cancer, also known as colon cancer, is one of the most common and deadly cancers in the world. Traditional chemotherapy is good, but it has big downsides, like harming other parts of the body and making people sick all over. Polymeric micelles give a new way to fix these problems by being easier on the body, breaking down naturally, and staying in the blood longer. The polymeric micelles, which are loaded with drugs, are sheltered within the tumor, which leads to a reduction in off-site effects and an increase in the targeting and accumulation of chemotherapeutics at the cancer site. This review paper elaborates on the current status of polymeric micelles as a method for nano-drug delivery for chemotherapy, emphasizing their efficacy in managing cancer. The paper also talks about the various types of copolymers that are used to create polymeric micelles, the different types of micelles, their physicochemical properties, the preparation process, characterization, and their application in cancer diagnostics.

Effect of PEG concentration on drug release from PLA-PEG copolymers: A molecular dynamics simulation study

Mercaptopurine (6-MP), a cancer medication limited by its hydrophobic properties, was studied using molecular dynamics simulations with biodegradable copolymers (PLA-PEG, PLA-PEG-PLA, PEG-PLA-PEG) as drug carriers. The influence of PEG concentration in copolymers on drug release was examined. Results revealed that blending PEG with PLA or copolymerizing them affected hydrogen bond numbers and mixing energy in the drug carrier, dependent on copolymer type and PEG concentration. Introducing PEG into PLA chains increased hydrogen bonds and energy, but copolymerizing PLA and PEG did not consistently enhance hydrogen bond energy (PLA-PEG-PLA > PEG-PLA-PEG > PLA-PEG). Mixing energy was consistently elevated by PEG-PLA copolymerization, ranked PEG-PLA-PEG > PLA-PEG > PLA-PEG-PLA. The fastest drug release was observed with the PLA&PEG-10.9 carrier, attributed to weak PLA-PEG chain connections facilitating water access to PEG. Increasing PEG content reduced chain mixing energy, slowed drug release via stronger chain hydrogen bonding. Notably, PEG-PLA-PEG-8.7 exhibited the highest drug release rate due to quicker water penetration. The copolymer type and chain length were found to impact water molecule access to PEG and drug release rate significantly.

PDMS-based copolymers with polyurea blocks and 1,2,3-triazole blocks obtained by CuAAC polymerization for 3D printing

Polydimethylsiloxanes with improved mechanical properties that can be processed by 3D printing are in high demand for scientific and practical applications. In our article, we proposed the synthesis of new PDMS copolymers with urethane and triazole fragments using the CuAAC reaction mechanism, as well as 3D printing with the obtained copolymers. Two types of copolymers, with molecular weights of 3000 and 6000 Da of PDMS block length, were prepared and characterized by GPC, IR spectroscopy, TGA, DSC, TMA, SAXS, and rheological measurements to determine their physicochemical properties. The synthesized copolymers were found to be suitable for processing by extrusion 3D printing. This demonstrated the ability to 3D print macroscale models of varying shapes and complexity. The resulting materials retained their printed shape over time.

Preparation and Properties of Temperature Resistant and Salt Resistant Lotion Fracturing Fluid Thickener

In order to prepare fracturing fluid with excellent solubility, temperature resistance, salt resistance and shear resistance, acrylamide (AM), 2-acrylamide-2-methylpropanesulfonic acid (AMPS) and acryloylmorpholine (ACMO) were copolymerized, and anionic cellulose was introduced to synthesize a new type of polyacrylamide copolymer p (AM/AMPS/ACMO) through inverse emulsion polymerization. The structure and morphology were characterized by infrared spectroscopy and scanning electron microscope. The results showed that in 0, 5, 10, 20, 50, 100, 150 and 200 g/L NaCl, CaCl2, and MgCl2 solutions, the viscosity of p (AM/AMPS/ACMO) solution modified by PVA fiber was always higher than that of conventional PAM solution, and the polymer modified by PVA fiber had better salt resistance. The anionic cellulose modified thickener was sheared at 120 ℃ and 150 ℃ for 1 h at 170 s－1, and the viscosity after shearing is 89.92 mPa·s and 80.10 mPa·s, respectively, which is much higher than the viscosity required by the general technical conditions of fracturing fluid more than 50 mPa·s, indicating that anionic cellulose modified p (AM/AMPS/ACMO) has good temperature and shear resistance.

Development of Amorphous Solid Dispersion Sustained-Release Formulations with Polymer Composite Matrix-Regulated Stable Release Plateaus.

This study was designed to develop ibuprofen (IBU) sustained-release amorphous solid dispersion (ASD) using polymer composites matrix with drug release plateaus for stable release and to further reveal intrinsic links between polymer' matrix ratios and drug release behaviors. Hydrophilic polymers and hydrophobic polymers were combined to form different composite matrices in developing IBU ASD formulations by hot melt extrusion technique. The intrinsic links between the mixed polymer matrix ratio and drug dissolution behaviors was deeply clarified from the dissolution curves of hydrophilic polymers and swelling curves of composite matrices, and intermolecular forces among the components in ASDs. IBU + ammonio methacrylate copolymer type B (RSPO) + poly(1-vinylpyrrolidone-co-vinyl acetate) (PVP VA64) physical mixtures presented unstable release behaviors with large error bars due to inhomogeneities at the micrometer level. However, IBU-RSPO-PVP VA64 ASDs showed a "dissolution plateau phenomenon", i.e., release behaviors of IBU in ASDs were unaffected by polymer ratios when PVP VA64 content was 35% ~ 50%, which could reduce risks of variations in release behaviors due to fluctuations in prescriptions/processes. The release of IBU in ASDs was simultaneously regulated by the PVP VA64-mediated "dissolution" and RSPO-PVP VA64 assembly-mediated "swelling". Radial distribution function suggested that similar intermolecular forces between RSPO and PVP VA64 were key mechanisms for the "dissolution plateau phenomenon" in ASDs at 35% ~ 50% of PVP VA64. This study provided ideas for developing ASD sustained-release formulations with stable release plateau modulated by polymer combinations, taking full advantages of simple process/prescription, ease of scale-up and favorable release behavior of ASD formulations.

The effects of grafted multiple phenolic antioxidants onto polymethacrylate type pour point depressants on the low-temperature flowability and oxidation stability of biodiesel blends

The enhancement of cold flow properties (CFPs) and oxidative stability (OS) in biodiesel-diesel blends typically involves the use of pour point depressants and antioxidants. However, a scant number of additives are capable of manifesting both pour point depression and antioxidant functionalities concurrently. This study explored the grafting of syringic acid (SA), 3,5-di-tert-butyl-4-hydroxybenzoic acid (DTBHA), and gallic acid (GA) onto polymethacrylate (PMA) type copolymers, culminating efficacious copolymers, namely PTG-SA, PTG-DTBHA and PTG-GA. The findings reveal that with the addition of 1500 ppm of PTG-GA, the CFPP and PP of B20 (20 vol% soybean biodiesel+80 vol% diesel) decrease by 10 and 18 °C respectively, and with the addition of 2000 ppm, the induction period (IP) of B20 can be extended from 1.34 to 8.69 h. In contrast, the application of PTG-SA and PTG-DTBHA to B20 led to inferior OS and CFPs as compared to PTG-GA. The inherent scientific mechanism that underlies this performance discrepancy was thoroughly investigated, scrutinizing it through the lens of co-crystallization and nucleation processes. This research underscores the potential of post-modification of PMA type pour point depressants with antioxidants, a strategy that not only bolsters the CFPs of B20 but also confers antioxidant attributes to the pour point depressants.

Recent advances of copolymer for water treatment.

Increasing water pollution due to anthropogenic activities prompts the quest for an effective water treatment method. Polymeric materials have gained attention as adsorbents for water purification. Membranes are majorly made from homopolymeric materials. However, recent studies have focused on using copolymeric materials for improved performance. In this review, the basics of copolymerization including various types of copolymers, synthetic approaches, and their applications in various water pollutants removal are discussed in detail. Advances in water treatment technology using copolymeric materials as adsorbent/membranes in the last 4 years are covered with insights into the future outlook and areas of improvement in terms of copolymer composites for water treatment. Studies from the literature did not only reveal effectiveness of copolymer as a flocculant/antifouling materials and in removal of selective toxic metals, oil, and microbes but also demonstrated recyclability of the copolymer sorbents/membrane. Full exploration of unique copolymer textural and structural properties could lead to great advancement in water treatment process. PRACTITIONER POINTS: The copolymer types and synthetic methods are discussed. Application of copolymer as adsorbent/membranes for water treatment is presented. Recent advances show good pollutants removal for toxic metals, oil, and organics. Copolymer composites have great potential as adsorbent/membranes for future use in water treatment processes.

PH-Dependent proteolytic activity of histidine-pendant polyacrylamides

Artificial enzymes with serine, aspartic acid, and histidine that mimic the catalytic triad of serine proteases have been studied. However, they were mainly investigated for their cleavage activity on low molecular-weight esters and amides, and there has been a lack of knowledge about their protein cleavage activity. We previously found that not only ternary polyacrylamides with serine, aspartic acid, and histidine but also homo-polyacrylamides with a single type of amino acid cleaved bovine and human serum albumins. These results suggested that the carboxy group, a common functional group in active polymers, may be involved in the expression of activity. In this study, we synthesized histidine polymers in which the carboxy group was changed to a carboxamido or amino group and investigated the relationships between structure and activity. Histidine homopolymers and histidine-acrylamide copolymers were incubated with bovine serum albumin at 37 °C for one week under different pH conditions and then analyzed by sodium dodecyl-sulfate polyacrylamide gel electrophoresis. In the case of histidine homopolymers, the carboxy-type homopolymers were active under weakly acidic to neutral conditions, while the carboxamido- and amino-type homopolymers were not active regardless of liquid properties. In the case of histidine-acrylamide copolymers, their activity was essentially the same as that of each type of histidine homopolymer, but for all types of copolymers, activity appeared under weakly basic conditions when the histidine monomer units were of a specific density. The carboxy-type copolymers with dual-mode activity showed different degradation patterns of bovine serum albumin under acidic and basic conditions. The structural features common to the active homopolymers and copolymers suggested that the carboxy group contributes to the activity under weakly acidic to neutral conditions, while the imidazole group of the histidine side chain and its density contribute to the activity under weakly basic conditions.

Synthesis and characterization of amino-functional polyesters composed of lactic acids and serine amino acids

Functional polyesters with good biocompatibility are always important biomaterials. In this study, poly (latide-co-N-trityl serine ester)s (P (LA-co-TSL)s) were synthesized through the copolymerization of lactide (LA) and N-trityl serine lactone (TSL) in toluene under 90 °C with the catalysis of diethylzinc. The molecular weight (Mn) of P (LA-co-TSL) with different TSL molar ratios (4.5%, 8.8%, 25.2%, 41.7% and 100 mol%) ranged from 3.7 kDa to 7.2 kDa with the polydipersity index (PDI) from 1.40 to 1.57. The chemical structure of poly (LA-co-TSL)s was characterized by FTIR, 1H NMR and 13C NMR spectroscopy. As the proportion of TSL in P (LA-co-TSL) increased, the glass transition temperature (Tg) of P (LA-co-TSL) increased gradually, from 56 °C of PLA to 161 °C of Poly (TSL). The initial weitht loss temperature of P (LA-co-TSL) increased as the ratio of TSL increased, from 172 °C of PLA to 230 °C of Poly (TSL). Upon removal of the N-trityl protecting group, amino functional poly (latide-co-serine ester) (P (LA-co-SL)) was realized and confirmd by FTIR and 1H NMR spectra. GPC displayed approximately 19.5% polyester backbone degradation during deprotection with trifluoroacetic acid. DSC analysis illustrated better crystallization properties of the copolyester after amino group deprotection. Using mPEG as an initiator, a new type of block copolymer, mPEG-b-poly (latide-co-N-trityl serine ester)s (mPEG-b-P (LA-co-TSL)s), was obtained. After N-trityl removal, mPEG-b-P (LA-co-TSL) displayed excellent cytocompatibility in L929 cell culture experiments.

Proton-conducting membranes based on Nafion® synthesized by using nanodiamond platform

New method of emulsion synthesis of Nafion®-type copolymer composition by using nanodiamond platform has been proposed and implemented. Produced polymeric coagulate saturated with diamonds (4.1 % wt.) possessed increased ionic capacity of the copolymer comparative to the analogue without diamonds. SEM patterns for coagulate membranes showed labyrinthine structures with diamonds integrated into copolymer without any segregation. This structuring provided necessary elastic and strength properties of new type membranes for hydrogen fuel cells. In new membranes synchrotron experiments exhibited a network of ionic channels which ensured a proton conductivity by one order of magnitude higher than that for the analogue produced of premade components.

Antioxidant Polymers with Phenolic Pendants for the Mitigation of Cellular Oxidative Stress.

Overproduction of reactive oxygen species (ROS) in cells is a major health concern as it may lead to various diseases through oxidative damage of biomolecules. Commonly used traditional small molecular antioxidants (polyphenols, carotenoids, vitamins, etc.) have inadequate efficacy in lowering excessive levels of ROS due to their poor aqueous solubility and bioavailability. In response to the widespread occurrence of antioxidant polyphenols in various biorenewable resources, we aimed to develop water-soluble antioxidant polymers with side chain phenolic pendants. Four different types of copolymers (P1-P4) containing phenyl rings with different numbers of hydroxy (-OH) substituents (0: phenylalanine, 1: tyrosyl, 2: catechol, or 3: gallol) were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization with a desired molar mass (8500-10000 g/mol) and a narrow dispersity (Đ ≤ 1.3). After successful characterizations of P1-P4, their in vitro antioxidant properties were analyzed by different methods, including 2,2-diphenyl-1-picrylhydrazyl (DPPH•), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS•+), 4,4'-diamino-3,3',5,5'-tetramethylbiphenyl (TMB), and β-carotene (βC) assays. Our results revealed that the gallol pendant polymers can effectively scavenge ROS. Furthermore, electron paramagnetic resonance (EPR) spectroscopy with DPPH• also confirmed the radical quenching ability of the synthesized polymers. The gallol pendant polymers, at a well-tolerated concentration, could effectively penetrate the macrophage cells and restore the H2O2-induced ROS to the basal level. Overall, the present approach demonstrates the efficacy of water-soluble antioxidant polymers with gallol pendants toward the mitigation of cellular oxidative stress.