Copolymer Research Articles

Reduction Polymerization of CO2 with Phenylene Silanes Catalyzed by Single Component B(C6F5)3

AbstractCO2 is an abundant C1 resource but a green‐house gas and chemically inert. Thus, its utilization has been a promising but challenging project. Herein, we report the unprecedented polymerization of CO2 and C6H4(SiMe2H)2 using B(C6F5)3 alone under mild conditions to give poly(silphenylene siloxane) accompanied by releasing CH4. The copolymerization can be extended to comonomers of phenylene silanes bearing functional groups. Moreover, it combines with Piers‐Rubinsztajn reaction to establish a tandem polymerization system to achieve super thermal resistant poly(siloxane‐co‐silphenylene siloxane)s. Density functional theory reveals that B(C6F5)3 is activated by silanes to form free HB(C6F5)2, which is the true active species for CO2 reducing to borylformate, the rate controlling step of the polymerization procedure. The subsequent multiple reductions of borylformate to CH4 and the step‐growth to poly(silphenylene siloxane)s can be fulfilled by both B(C6F5)3 and HB(C6F5)2, and the former shows a slightly higher activity. This work opens a new avenue of utilizing CO2 to fabricate polysiloxanes that is unable to access using current manners.

Triggering Ion Diffusion and Electron Transport Dual Pathways for High Efficiency Electrochemical Li+ Extraction.

Efficient electrochemical Li+ adsorption holds significant promise for lithium extraction, while the mismatched rate between Li+ diffusion and electron transport within the electrode material impedes the electrochemical activity and restricts the adsorption efficiency. To address this challenge, herein, we rationally design and integrate the ion and electron dual-conducting poly(vinyl alcohol)-polyaniline (PVA-PANI) copolymer (CP) within the H1.6Mn1.6O4 (HMO) electrode matrix to facilitate Li+ diffusion and electron transport. The Li+ diffusion coefficient (DLi+) increased from 3.03 × 10-10 to 5.92 × 10-10 cm2/s, while the charge transfer resistance (Rct) decreased from 53.73 to 29.57 ohm. Consequently, the HMO@CP electrode exhibits superior adsorption kinetics and a state-of-the-art high adsorption capacity of up to 49.48 mg/g. Comprehensive mechanistic studies reveal that the negatively charged hydroxyl groups (-OH) in PVA accelerate Li+ diffusion and that the conjugated structure and redox-active quinoid sites in PANI offer denser electron distribution and promote electron transport. This synergistic effect in CP significantly enhanced Li+ diffusion and electron transport, leading to electrochemical activity and adsorption efficiency. Our work highlights the critical role of simultaneously regulating the ion diffusion and electron transport dual pathways for optimizing Li+ adsorption performance and inspires development of the next generation electrochemical adsorption electrodes.

Development and validation study of compact biophotonic platform for detection of serum biomarkers

The application of advances in personalized medicine requires the support of in vitro diagnostic techniques aimed at the accurate, fast, sensitive, and precise determination of selected biomarkers. Herein, a novel optical centrifugal microfluidic device is developed for clinical analysis and point-of-care diagnostics. Based on compact disc technology, the integrated biophotonic system enables multiple immunoassays in miniaturized mode. The disposable microfluidic discs are made in cyclic olefin copolymer (COP), containing arrays of immobilized probes. In the developed approach, up to six patient samples can each be tested simultaneously. A portable instrument (<2 kg) controls the assay and the high-sensitive reproducible optical detection in transmission mode. Also, the instrument incorporates specific functionalities for personalized telemedicine.The device (analytical method, disc platform, reader, and software) has been validated to diagnose IgE-mediated drug allergies, such as amoxicillin and penicillin G. The total and specific IgE to β-lactam antibiotics were determined in human serum from patients (25 μL). The excellent analytical performances (detection limit 0.24 ng/mL, standard deviation 7–20 %) demonstrated that the developed system could have the potential for a broader impact beyond the allergy field, as it applies to other IVD tests.

Conducting co-polymer derived N, S co-doped metal-free hierarchical nanoporous carbon for robust electrochemical capacitor

The present investigation reported metal-free hierarchical porous and robust Nitrogen (N), Sulphur (S) co-doped carbon (NS-CoP@C) electrode for supercapacitor application. The NS-CoP@C was synthesized by single-step carbonization and activation of thiourea co-doped aniline-pyrrole co-polymer (CoP). The thiourea acted as a doping as well as activating agent. The data of three different electrode materials PANI-PPy co-polymer (CoP), PANI-PPy co-polymer derived Carbon (CoP@C) and N, S co-doped carbon derived from PANI-PPy co-polymer (NS-CoP@C) are compared in the present report. The electrode materials were initially characterized by various spectroscopic techniques. It is observed that among the three electrode material, NS-CoP@C possess higher specific surface area (SSA), high pore volume and hierarchal porous structure with a better mesopore-to-micropore volume ratio. In a three-electrode system, NS-CoP@C possesses a high specific capacitance of 344.2 F/g @ 0.5A/g. Moreover, NS-CoP@C electrode was used to fabricate an all solid-state (PVA-1 M H2SO4 polymer gel electrolyte) and aqueous (1 M H2SO4 electrolyte) symmetrical supercapacitor devices in the two-electrode system. This NS-CoP@C electrode was used as both positive and negative electrode material in both types of devices. Among them, the solid-state device operates at a wide potential window of 2 V, as a consequence delivering an implausible energy and power density of 45.25 Wh/kg and 1025.64 W/kg while maintaining a capacity retention of 90.1 % even after 8500 charge-discharge cycles. Hence, the excellent performance of conducting PANI-PPy co-polymer-derived N, S co-doped carbon paved new ground for developing an alternative electrode for futuristic energy storage devices.

Formulation, Configuration, and Physical Properties of Dental Composite Resin Containing a Novel 2π + 2π Photodimerized Crosslinker - Cinnamyl Methacrylate: An In Vitro Research.

To formulate and characterize the chemical structure of a new dental composite with photodimerized cinnamyl methacrylate (PD-CMA) photo-crosslinking comonomer and to evaluate the monomer-to-polymer conversion (MPC) and glass transition temperature (Tg) of the new composite copolymers. CMA was PD by ultraviolet C-type (UVC) irradiation. The research groups were a control group C0 without PD-CMA and two trial groups: E10 (10 wt. % PD-CMA substituted in the base comonomers (B) and diluent (D) mixture); E20 (20 wt.% PD-CMA completely replacing the diluent (D) monomer). Infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies were employed for ascertaining copolymerization (CP). The surface features and composition of the copolymers were explained by field-emission scanning electron microscopy (FESEM) and energy dispersive X-ray (EDX) spectroscopy, respectively. The MPC and Tg of the copolymers were assessed using FTIR and differential scanning calorimetry, respectively. Statistical tests were used to compare the groups. The configuration of the new copolymers P (BD-Co-CMA) and P(B-Co-CMA) was confirmed. The MPC% and T g of the copolymers were better than the control. PD-CMA at 20 wt. % in the P (B-Co-CMA) copolymer exhibited the highest MPC% and Tg. The incorporation of PD-CMA in the composite resin resulted in new P (BD-Co-CMA) and P (B-Co-CMA) copolymers with improved MPC% and Tg. The substitution with PD-CMA offset the shortcomings of the conventional BD comonomers concerning the mechanical properties and biocompatibility of the restorative composite resin. This might ameliorate the restorations in vivo longevity and serviceability.

Toward the Formation of the Solid Electrolyte Interphase on Alkaline Metal Anodes: Ab Initio Simulations**

AbstractThe transition from lithium‐based energy storage to post lithium systems plays a crucial part in achieving an environmentally sustainable energy infrastructure. Prime candidates for the replacement of lithium are sodium and potassium batteries. Despite being critical to battery performance, the solid electrolyte interphase (SEI) formation process for Na and K batteries remains insufficiently understood, especially compared to the well‐established lithium systems. Using ab initio molecular dynamics (AIMD) simulations based on density functional theory (DFT) calculations, we study the first steps of SEI formation upon the decomposition of typical solvent molecules on lithium, sodium and potassium metal anodes. We find that two dominant products form during the early SEI formation of cyclical carbonates on alkali metal anodes, carbon monoxide and alkali‐carbonate. The carbonate‐producing reaction is thermodynamically favorable for all tested metals, however, Na and K exhibit a much stronger selectivity than Li towards carbonate formation. Furthermore, we propose a previously unknown reaction mechanism for the CO polymerization on metallic lithium.

Degradation of Chloroform by Zerovalent Iron: Effects of Mechanochemical Sulfidation and Nitridation on the Kinetics and Mechanism.

Chloroform (CF) is a widely used chemical reagent and disinfectant and a probable human carcinogen. The extensive literature on halocarbon reduction with zerovalent iron (ZVI) shows that transformation of CF is slow, even with nano, bimetallic, sulfidated, and other modified forms of ZVI. In this study, an alternative method of ZVI modification─involving simultaneous sulfidation and nitridation through mechanochemical ball milling─was developed and shown to give improved degradation of CF (i.e., higher degradation rate and inhibited H2 evolution reaction). The composite material (denoted as S-N(C)-ZVI) gave synergistic effects of nitridation and sulfidation on CF degradation. A complete chemical reaction network (CRN) analysis of CF degradation suggests that O-nucleophile-mediated transformation pathways may be the main route for the formation of the terminal nonchlorinated products (formate, CO, and glycolic polymers) that have been used to explain the undetected products needed for mass balance. Material characterizations of the ZVI recovered after batch experiments showed that sulfidation and nitridation promoted the formation of Fe3O4 on the S-N(C)-ZVI particles, and the effect of aging on CF degradation rates was minor for S-N(C)-ZVI. The synergistic benefits of sulfidation and nitridation on CF degradation were also observed in experiments performed with groundwater.

Multifunctional Architectures of Cyclic Dipeptide Copolymers and Composites, and Modulation of Multifaceted Amyloid-β Toxicity.

Alzheimer's disease (AD) is a major neurodegenerative disorder primarily characterized by the β-amyloid (Aβ42) misfolding and aggregation-associated multifaceted amyloid toxicity encompassing oxidative stress, neuronal death, and severe cognitive impairment. Modulation of Aβ42 aggregation via various structurally anisotropic macromolecular systems is considered effective in protecting neuronal cells. In this regard, we have developed a cyclic dipeptide (CDP)-based copolymer (CP) and explored its material and biomedical properties. Owing to the structural versatility, CDP-CP forms solvent-dependent anisotropic architectures ranging from dense fibers and mesosheets to vesicles, which are shown to interact with dyes and nanoparticles and mimic synthetic protocells, providing a conceptually new approach to achieve advanced functional materials with the hierarchical organization. CP upon interaction with gold nanoparticles (GNP) and polyoxometalate (POM) generated faceted architectures (CP-GNP) and the nanocomposite (CP-POM), respectively. CP-GNP and CP-POM have shown remarkable ability to inhibit Aβ42 aggregation, dissolve the preformed aggregates, and scavenge reactive oxygen species (ROS) to ameliorate multifaceted amyloid toxicity. In cellulo studies show that CP-GNP and CP-POM protect neuronal cells from Aβ42-induced toxicity and reduce lipopolysaccharide (LPS)-activated neuroinflammation at sub-micromolar concentration. To our knowledge, this is the first report on the hierarchical organization of CDP-CP into 1D-to-2D architectures and their organic-inorganic hybrid nanocomposites to combat the multifaceted amyloid toxicity.

Structurally stable and surface-textured polylactic acid/copolymer/poly (ε-caprolactone) blend-based electrospun constructs with tunable hydroxyapatite responsiveness

Functionally-designed nanotextured and copolymer (COP) mediated PLA/PCL (70:30 w/w) blend-based interface-engineered electrospun mats (EMs) based constructs, with phase-specific interactions, have been successfully developed. The thermal stability of constructs remained up to ∼300–350 °C, while the crystallinity reduced to ∼12–23 %, indicating enhanced pliability. The tensile strength increased by ∼75 % without much compromise in the tensile modulus whereas the dynamic relaxation response of the constructs shifted to lower temperatures upon the incorporation of ≥ 2.5 phr (parts per hundred parts of resin) of COP. The zeta potential evaluated from radial surface exposure intensity could be manipulated by controlling the extent of COP content (−60 mV for ∼5 phr COP) which in turn led to the dynamics of site-specific charge neutralization driven attachment of Ca2+ ions (∼13 % for ∼5 phr COP) of the nano-hydroxyapatite (n-HA). Such uniformly dispersed, n-HA attached, and surface-decorated (COP ≤ 5 phr) EMs enabled the selective L929 fibroblast cell attachment (∼200 % cell viability for ∼2.5 phr COP). Thus, the approach may prove to augment the biomineralization of Ca and apatite-driven healing kinetics amongst implant-seeking and inflammation-prone sites and thereby, paving a new pathway for controlled and targeted healing of bone, cartilage, dental gums, and other sites demanding n-HA and/or calcium-phosphorus assisted healing mechanism.

Anode Catalytic Dependency Behavior on Ionomer Content in Direct CO Polymer Electrolyte Membrane Fuel Cell

Anode Catalytic Dependency Behavior on Ionomer Content in Direct CO Polymer Electrolyte Membrane Fuel Cell

Polymerization of CO4 groups in carbonates

Polymerization of CO₄ groups in carbonates

Portraiture and Double Bond Conversion of a Monomethacrylate-based Oral Prosthetic Resin Substituted with a Novel Tri(azine-acrylate) Cross-linker

To formulate, design, and chemically characterize a novel denture base resin (DBR) copolymer containing triazine-based antimicrobial comonomer and also to evaluate the double bond conversion (DC) in the copolymer with various concentrations of the comonomer by fourier transform infrared (FTIR) spectroscopy. The study groups comprise a control group G0 in which the specimens (n = 10) were polymerized without the triazine comonomer and trial groups G10 and G20 where the polymerized specimens (n = 10 each) contained 10 and 20% triazine comonomer, respectively. FTIR was employed to ascertain and evaluate copolymerization (CP) and DC. The obtained DC values were subjected to statistical analysis. A new denture base copolymer containing antimicrobial triazine comonomer was formed with ascertained copolymerization and higher DC than the control group. Twenty percent triazine comonomer in the copolymer exhibited the maximum DC. Incorporation of the antimicrobial comonomer copolymerized with DBR to form a novel denture base copolymer exhibiting high DC. The novel denture base copolymer may prevent the microbial adhesion on the denture surface thereby preventing denture-induced stomatitis in the edentulous patients. Nonetheless, this novel copolymer may enhance the other necessary properties of the DBR and would ameliorate the living quality of the senile geriatric population with good in vivo serviceability.

Electrochemical Polymerization of a Carbazole‐Tethered Cobalt Phthalocyanine for Electrocatalytic Water Oxidation

AbstractThe four‐electron oxidation of water (2H2O→O2+4H++4e−) is critical for artificial photosynthesis. In nature, this reaction is efficiently catalyzed by photosystem II via cooperative catalytic centers and charge transporters. However, the integration of water oxidation catalysts and charge transporters in artificial systems remains challenging. In this report, a function‐integrated water oxidation catalyst produced by the electrochemical polymerization of a cobalt phthalocyanine complex bearing carbazole moieties is described. The monomer complex, Co(czPc) (H2czPc=tetrakis(9H‐carbazole‐9‐ethoxy)phthalocyanine), was synthesized and characterized by elemental analysis, matrix‐assisted laser desorption/ionization mass spectrometry, and Fourier transform infrared and ultraviolet‐visible spectroscopy measurements. The electrochemical polymerization of Co(czPc) was confirmed using cyclic voltammetry measurements and yielded poly‐Co(czPc) on the surface of a glassy carbon electrode. Poly‐Co(czPc) showed excellent charge‐transport ability and superior electrocatalytic water oxidation performance to that of the corresponding nonpolymeric system.

Ga and Ti co-doped In2O3 films for flexible amorphous transparent conducting oxides

We designed Ga and Ti co-doped In2O3 (IGTO) films to use as a flexible and transparent amorphous conducting oxide electrode in thin film heaters (TFHs) and flexible touch screen panels (FTSPs) for automobiles. The properties of the IGTO electrodes deposited on cyclic olefin copolymer (COP) at room temperature were investigated as a function of the O2/(Ar + O2) flow ratio, to confirm the best sputtering condition for transparent and flexible electrode. Depending on the oxygen flow ratio, the IGTO/COP electrodes showed sheet resistance of (39.3 – 1.57) × 104 Ohm/sq, an average transmittance of (84.90 – 87.12) % at visible wavelength area, and a surface roughness of (0.95 – 3.23) nm. In addition, IGTO/COP samples exhibited good mechanical flexibility with critical bending radius of 3 mm, which is enough to be used as FTSPs. From the previously mentioned results, we found the amorphous IGTO/COP to be a promising flexible and transparent electrode for curved TFHs and FTSPs. The flexible IGTO/COP TFHs demonstrated a saturated temperature of 78.6 °C when applied with low operating direct current (DC) of 8 V, due to its low sheet resistance. In addition, the IGTO/COP FTSPs showed very stable touch sensitivity, even at a bent state. We found that the optimized IGTO/COP is a promising flexible and transparent electrode for next-generation automobiles.

Structure-Property Relationships of Inorganic-Organic Hybrid Semiconducting Se-Fe-Cu-CO Polymers.

A novel family of inorganic-organic-hybrid SeFe3(CO)9-dipyridyl two- and one-dimensional Cu polymers was synthesized via the three-component liquid-assisted grinding (LAG) of [Cu(MeCN)4]+, inorganic cluster [SeFe3(CO)9]2- (1), and rigid conjugated dipyridyls 4,4'-dipyridyl (dpy) and 1,2-bis(4-pyridyl)ethylene (bpee) or flexible conjugation-interrupted dipyridyls 1,2-bis(4-pyridyl)ethane (bpea) and 1,3-bis(4-pyridyl)propane (bpp). They included a cluster-linked 2D polymer, [(μ4-Se)Fe3(CO)9Cu2(MeCN)(dpy)1.5]n (1-dpy-2D), a cluster-pendant 1D chain, [(μ3-Se)Fe3(CO)9Cu2(dpy)3]n (1-dpy-1D), cluster-blocked 1D polymers, [(μ3-Se)Fe3(CO)9Cu2(L)]n (1-L-1D, L = bpee, bpea), and a cluster-linked 2D polymer, [(μ4-Se)Fe3(CO)9Cu2(bpp)2]n (1-bpp-2D). The reversible dimensionality transformations of these three types of polymers accompanied by the change in coordination modes of 1 were achieved by the LAG addition of 1/[Cu(MeCN)4]+ or dipyridyl ligands. These polymers were found to possess tunable low-energy gaps (1.49-1.72 eV) that increased in the order regarding their structural features: cluster-linked 1-dpy-2D and 1-bpp-2D, cluster-blocked 1-bpea-1D and 1-bpee-1D, and cluster-pendant 1-dpy-1D and [(μ3-Se)Fe3(CO)9Cu2(L)2.5]n (L = bpee, 1-bpee-2D; bpea, 1-bpea-2D), indicative of the importance of the participation of cluster 1. The measured electrical conductivities of 1-bpp-2D, 1-bpea-1D, and 1-dpy-1D were 3.13 × 10-7, 2.92 × 10-7, and 2.30 × 10-7 S·cm-1, respectively, which were parallel for the trend in their energy gaps, revealing semiconducting behaviors, supported by XPS, XANES, and DFT calculations. The surprising semiconductivity of the conjugation-interrupted bpp-linked 1-bpp-2D was mainly ascribed to electron transport via C-H···O(carbonyl) hydrogen bonds and aromatic C-H···π contacts within its closely packed 2D layers. Water-/light-stable polymers 1-bpp-2D, 1-bpea-2D, and 1-dpy-1D were also demonstrated to exhibit excellent pseudo-first-order photodegradation toward nitroaromatics and organic dyes, where cluster-linked polymer 1-bpp-2D performed the best, as predicted by its structural features and narrow energy gap.

Ring-Opening Polymerization of CO2-Based Disubstituted δ-Valerolactone toward Sustainable Functional Polyesters.

3-Ethylidene-6-vinyltetrahydro-2H-pyran-2-one (EVL) is a disubstituent δ-lactone derived from CO2 and 1,3-butadiene. In this contribution, we report the ring-opening polymerization (ROP) of EVL with β-butyrolactone (BBL) as the comonomer catalyzed by scandium triflate [Sc(OTf)3]. The obtained polyester bearing active unsaturated bonds has the weight-average molecular weight (Mw) of 4.1 kg/mol, in which the EVL content is 38 mol % in accordance with the initial ratio of 40 mol %. The copolymers are characterized in detail and the cationic ROP mechanism has been confirmed by kinetic study, chain end analysis and density functional theory (DFT) calculation. The modification of the unsaturated bonds in EVL repeating units via the thio-ene click reaction with mercapto-ended polysarcosine polysarcosine yields the amphiphilic grafting polymers. It is a CO2 fixation approach toward the functional poly(EVL-r-BBL) that is promising as a degradable polyester precursor for adhesive or surface-coating materials.

Conductive chitosan-graft-polyaniline copolymer: synthesis and characterization

Conductive chitosan-graft-polyaniline copolymer: synthesis and characterization

Copolymerization of Ring-Opening Oxaspiro Comonomer with Denture Base Acrylic Resin by Free-Radical/Cationic Hybrid Polymerization.

Background:Polymerization shrinkage is an innate characteristic of thermo-polymerized denture base acrylic resin. Volumetric shrinkage is still a problem, although myriad material modifications. Ring-opening oxaspiro monomers have promising volumetric expansions of about 7%. These monomers have diminished the shrinkage in dental filling resins through copolymerization (CP). However, their CP with denture base resins is not reported yet.Purpose:The aim is to confirm the CP of an oxaspiro monomer with methyl methacrylate (MMA) by radical-cationic hybrid polymerization and to assess the degree of conversion (DC) of the formed copolymer.Materials and Methods:The oxaspiro monomer was synthesized by a transesterification reaction. The study groups were based on the composition and thermo-polymerization method. The control and E1 groups were thermo-polymerized in water-bath, whereas the E2 group in a laboratory autoclave. Both E1 and E2 groups contained the oxaspiro monomer and cationic initiator. E2 group had an additional radical initiator. The CP and DC were confirmed and assessed by infrared spectroscopy.Results:Accentuation of carbonyl peak, the disappearance of the spiro-carbon peak, and the appearance of ether linkages in experimental groups confirmed the ring-opening. E2 group had the highest DC.Conclusion:The oxaspiro monomer successfully copolymerized with MMA and had good DC.

Inhibition for Zn Corrosion by Starch Grafted Copolymer

Inhibition for Zn Corrosion by Starch Grafted Copolymer

Effect of microstructure on impact strength of impact polypropylene copolymers

Effect of microstructure on impact strength of impact polypropylene copolymers