Acrylic Acid Copolymer Research Articles

Controlling the Composition Profile of Acrylic Acid Copolymers by Tuning the pH of Polymerization in Aqueous Dispersed Media

Controlling the Composition Profile of Acrylic Acid Copolymers by Tuning the pH of Polymerization in Aqueous Dispersed Media

Anti-freezing conductive zwitterionic composite hydrogels for stable multifunctional sensors

Zwitterionic conductive hydrogels have shown potential application in wearable strain and pressure sensors. However, there are still fundamental challenges to achieve zwitterionic hydrogels with excellent mechanical properties, able to keep flexibility at sub-zero temperatures. To overcome these limitations, a zwitterionic conductive hydrogel was fabricated in this work by in-situ polymerization of aniline (ANI) monomer in a copolymer of sulfobetaine methacrylate (SBMA) and acrylic acid (AA) matrix. The obtained hydrogel possesses outstanding anti-freezing performance (without obvious loss of stretchability at −18 °C) and water-retaining properties, due to the introduction of LiCl on the zwitterionic polymer matrix. The synergy of chemical and physical crosslinking between poly (SBMA-co-AA) and polyaniline (PANI) networks enhance the mechanical performance of the zwitterionic hydrogel, that exhibits a fracture tensile strength of 470 kPa, and a fracture strain up to 600 %. Additionally, the integration of PANI confers stable conductivity (2.23 S m−1, maintained at 1.89 S m−1 even at −18 °C), high sensitivity (GF = 1.74), and short response and recovery times (223 ms and 191 ms, respectively). The hydrogel can be applied as a flexible sensor to accurately detect various human motions. This work provides a feasible strategy for developing wearable multifunctional sensors in a wide working temperature range.

Enhanced Water Absorbency and Water Retention Rate for Superabsorbent Polymer via Porous Calcium Carbonate Crosslinking.

To improve the water absorbency and water-retention rate of superabsorbent materials, a porous calcium carbonate composite superabsorbent polymer (PCC/PAA) was prepared by copolymerization of acrylic acid and porous calcium carbonate prepared from ground calcium carbonate. The results showed that the binding energies of C-O and C=O in the O 1s profile of PCC/PAA had 0.2 eV and 0.1-0.7 eV redshifts, respectively, and the bonding of -COO- groups on the surface of the porous calcium carbonate led to an increase in the binding energy of O 1s. Furthermore, the porous calcium carbonate chelates with the -COO- group in acrylic acid through the surface Ca2+ site to form multidirectional crosslinking points, which would increase the flexibility of the crosslinking network and promote the formation of pores inside the PCC/PAA to improve the water storage space. The water absorbency of PCC/PAA with 2 wt% porous calcium carbonate in deionized water and 0.9 wt% NaCl water solution increased from 540 g/g and 60 g/g to 935 g/g and 80 g/g, respectively. In addition, since the chemical crosslinker N,N'-methylene bisacrylamide is used in the polymerization process of PCC/PAA, N,N'-methylene bisacrylamide and porous calcium carbonate enhance the stability of the PCC/PAA crosslinking network by double-crosslinking with a polyacrylic acid chain, resulting in the crosslinking network of PCC/PAA not being destroyed after water absorption saturation. Therefore, PCC/PAA with 2 wt% porous calcium carbonate improved the water-retention rate by 244% after 5 h at 60 °C, and the compressive strength was approximately five-times that of the superabsorbent without porous calcium carbonate.

COMPOSITE MATERIALS BASED ON ALICYCLIC COPOLYIMIDE AND ACRYLIC ACID COPOLYMER WITH ACRYLAMIDE

Progress in polymer materials science is mainly associated with the development of new composite materials, created by the introduction of modifying additives into the matrix polymer which which improve polymer characteristics due to their properties. The purpose of this work is to obtain composite materials with improved thermal and mechanical properties from copolyimide based on dianhydrides of tricyclotetracarboxylic and diphenyloxydtetracarboxylic acids with diaminodiphenyl ether modified by a copolymer of acrylic acid with acrylamide. Results and discussion. Polymer compositions of copolyimides of arylalycyclic structure in combination with acrylic acid copolymer and acrylamide, as well as composite materials (film) based on them, were obtained. It was found that with an increase in the content of the added component from 0.35 to 2.0 wt%, uniformity is maintained in the polymer mixture. The infrared (IR) spectroscopy method shows that during formation of the above polymer mixtures the interaction of functional groups of the polymers under study with the formation of hydrogen bonds, which determine the homogeneity of the mixture. By methods of thermogravimetry and stretching of the sample with a constant deformation rate were used to determine, respectively, the thermal resistance and mechanical properties of the developed composite films. The increase of thermal resistance and strength of the film is explained by the formation of partial intermolecular cross-linking between the components of the mixture and the elasticity of the material – with the plasticizing effect of the additive. Conclusion. Polymer mixtures were obtained and composite films were molded on their basis.

Design and fabrication of superamphiphobic coating based on raspberry-like F–SiO2@PSA hybrid nanocomposite particles

Emulsifier-free polymerization was employed to prepare the submicron spherical PSA (the copolymer of styrene and acrylic acid), then SiO2 was grown on the surface of the PSA by sol-gel method to form F–SiO2@PSA particles. It was found that when styrene: acrylic acid = 2.5:1 and tetraethyl orthosilicate: PSA was between 2.17:1 and 6.38:1, a perfect raspberry-like structure could be obtained. The coating based on F–SiO2@PSA particles exhibited contact angles of 167.3 ± 1.4°, 152.1 ± 1.5°,150.3 ± 1.6°, 150.9 ± 1.6°, 142.2 ± 1.7°, 143.7 ± 1.5° and 146.6 ± 1.9° to water, diiodomethane, soybean oil, rapeseed oil, hexadecane, kerosene, and waste engine oil, respectively. The F–SiO2@PSA coating could reduce the adsorption of protein by 90% compared with the control surface. It was observed that bacteria and platelets could hardly adhere to the coating surface after 24 h of E. coli culture and 3 h of platelet-rich plasma immersion. The anti-adhesion to proteins, platelets, and bacteria will give the coating a promising application in the medical field.

Development of an acrylic acid-functionalized molecularly imprinted polymeric material for chiral recognition of S-ketamine

This study details the chiral identification of S-ketamine and the successful optical resolution of the racemic mixture of (±)-ketamine. The study outlines the development of a stereo-selective polymer material that is constructed using a cross-linked copolymer of 4-vinylphenol and acrylic acid. The initial step involved the synthesis of a chiral monomer precursor derived from S-ketamine and acryloyl chloride, which was then subjected to elemental analysis, Fourier transform infrared (FTIR), and nuclear magnetic resonance (NMR) spectroscopy for analysis. The amide derivative was free-radical copolymerized with 4-vinylphenol and divinylbenzene, and the resulting polymer resin was treated with alkali and then acid to break the amide linkage and get the S-ketamine out of the polymeric material. FTIR spectra and SEM were used to characterize the resulting molecularly imprinted polymer, and the material was tested for its ability to selectively remove S-ketamine under a range of conditions. Adsorption followed the Langmuir model with a maximum capacity of 137 ± 1 mg/g, and the findings showed that the optimum adsorption occurred at pH 7. Also, the optical resolution was performed using a column, with estimated enantiomeric excess values of 96% for R-ketamine and 81% for S-ketamine in the loading and recovery solutions.

Cellulose-g-poly (acrylic acid) interpenetrated by fulvic acid for potential Cu (II) removal from wastewater

The cellulose-g-poly (acrylic acid) copolymer preparation in the presence of fulvic acid as an interpenetrating agent (C-g-PAA/FA) has been successfully conducted using gamma radiation. The acrylic acid was utilized as a functional monomer and N, N’-methylene bisacrylamide was used as a crosslinking agent. The fulvic acid addition to C-g-PAA was intended to enhance the number of functional groups responsible for the chelating agent. The infrared spectra of the obtained copolymer verified the incorporation of fulvic acid and acrylic acid in the cellulose network structure by the appearance of phenyl vibration and changes in the carbonyl vibration at 1560 and 1725 cm−1, respectively. Moreover, the thermogravimetric analysis showed that the C-g-PAA/FA increased the thermal resistance of the cellulose structure, which could be explained by the formation of robust and more chemical bonds that contributed to the network structure. Scanning electron microscope images revealed that the C-g-PAA/FA possesses a more compact and stronger network structure compared to pristine cellulose. Energy-dispersive X-ray analysis confirmed the presence of copper ions on the surface of C-g-PAA/FA after Cu (II) removal. In addition, the C-g-PAA/FA has effectively been used as Cu (II) removal in the aqueous solution, with a removal percentage of up to 56 %.

Enhanced mechanical, thermal performance and kinetics of thermal degradation of silicone rubber/ethylene–vinyl acetate copolymer/halloysite nanoclay nanocomposites compatibilized by ethylene–acrylic acid copolymer

Enhanced mechanical, thermal performance and kinetics of thermal degradation of silicone rubber/ethylene–vinyl acetate copolymer/halloysite nanoclay nanocomposites compatibilized by ethylene–acrylic acid copolymer

Stretchable, self-healable and highly conductive natural-rubber hydrogel electrolytes for supercapacitors: Advanced wearable technology

Promising advancements in energy technologies lie in the development of highly flexible hydrogel electrolytes, which offer biodegradability, cost-effectiveness, and safety. However, striking a balance between stretchability, remarkable ionic conductivity, and self-healing ability remains challenging. In this research, we present a novel approach involving the utilization of epoxidized natural rubber (ENR)/acrylamide (AAm)/acrylic acid (AA) copolymer hydrogel electrolytes formed through a free radical mechanism. To further enhance the conductivity, hydrogel electrolytes were immersed in 1 M sodium sulfate (Na2SO4) salt solutions for varying periods. By capitalizing on the hydrogen bonding and electrostatic interactions within the hydrogels and the hydrogel-salt interaction, the resulting hydrogel exhibited an impressive ionic conductivity of 19.4 × 10−2 S/cm, a stretchability of 550 % from its initial length, and demonstrated self-healing capabilities. Additionally, employing symmetrical porous carbon electrodes, the hydrogel-based electric double layer capacitor (EDLC) achieved an outstanding specific capacitance of 55.65 F/g, enduring stable cycling over 3500 cycles without significant discharge. Notably, the mechanical strength of the hydrogel is significantly improved after the self-healing process. Importantly, this study highlights the significant role of immersion time in improving the ionic conductivity and functionality of hydrogel electrolytes.

Impact of composition and salinity on swelling and gel strength of poly (acrylamide-co-acrylic acid) preformed particle gel

The effects of various material compositions and reservoir environments on the ultimate strength and swelling kinetics of a commercial preformed particle gel (PPG) have been investigated. This study used different ratios of acrylamide and acrylic acid copolymers with a specific crosslinker concentration. Results have indicated that increasing the acrylic acid proportion enhances the PPGs’ ability to swell but weakens their network structure. In contrast, increasing the crosslinker content decreases the swelling ratio and increases the gel strength. The highest equilibrium swelling capacity among the six preformed particle gel samples was obtained for PPG2, which has the highest acrylic acid amount and the lowest crosslinker content, with a swelling ratio of 2400 g/g in deionized water and 59.8 g/g in brine 1 (67535.8 mg/l). On the contrary, PPG5, with the lowest acrylic acid and highest crosslinker content, has a swelling capacity of 239 g/g and more than 17 g/g in distilled and brine 1, respectively. Yet, PPG5 has the highest swollen gel strength of 615.5 Pa in deionized water and 3344 Pa in brine 1. The PPGs’ swelling ratios showed stepwise improvements along with increasing temperature, notably after 50 °C, yet, the storage modulus (G′) was negatively affected. The PPGs revealed the highest swelling behavior in pH 6–8, decreasing dramatically in more acidic and basic conditions. The swelling ratios of the PPGs in brine 1 at 50 °C were between 12 and 32 g/g, having strengths in the range of 566–5508 Pa, depending on the crosslinker ratio. The PPGs also demonstrated the ability to compete with other commercial PPGs as they have shown physical and thermal stability when aging at 50 °C, specifically those with high crosslinker content (PPG5).

Novel Natrosol/Pectin-co-poly (acrylate) based pH-responsive polymeric carrier system for controlled delivery of Tapentadol Hydrochloride

Background & ObjectivesThis study aimed to create a controlled delivery system for Tapentadol Hydrochloride by developing interpenetrating networks (IPNs) of Natrosol-Pectin copolymerized with Acrylic Acid and Methylene bisacrylamide, and to analyze the effects of various ingredients on the physical and chemical characteristics of the IPNs. MethodsNovel Tapentadol Hydrochloride-loaded Natrosol-Pectin based IPNs were formulated by using the free radical polymerization technique. Co-polymerization of Acrylic Acid (AA) with Natrosol and Pectin was performed by using Methylene bisacrylamide (MBA). Ammonium persulfate (APS) was used as the initiator of crosslinking process. The impact of ingredients i.e. Natrosol, Pectin, MBA, and Acrylic Acid on the gel fraction, porosity, swelling (%), drug loading, and drug release was investigated. FTIR, DSC, TGA, SEM and EDX studies were conducted to confirm the grafting of polymers and to evaluate the thermal stability and surface morphology of the developed IPNs. ResultsSwelling studies exhibited an increase in swelling percentage from 84.27 to 91.17% upon increasing polymer (Natrosol and Pectin) contents. An increase in MBA contents resulted in a decrease in swelling from 85 to 67.63%. Moreover, the swelling was also observed to increase with higher AA contents. Significant drug release was noted at higher pH instead of gastric pH value. Oral toxicological studies revealed the nontoxic and biocompatible nature of Natrosol-Pectin IPNs. Interpretation & ConclusionThe developed IPNs were found to be an excellent system for the controlled delivery of Tapentadol Hydrochloride.

ФОРМУВАННЯ ТА ВЛАСТИВОСТІ СТРУКТУРОВАНИХ ПОЛІАКРИЛАМІДНИХ ГІДРОГЕЛІВ З НАНОЧАСТИНКАМИ CdS

The new method of obtaining nanocomposite hydrogels with embedded mineral nanoparticles has been proposed. CdS nanoparticles have been synthesized in situ in hydrogel matrix based on the copolymer of acrylamide and acrylic acid under the conditions of diffusion fluxes of Cd2+ та S2- structure-forming ions. The formation of CdS nanoparticles in polymeric matrix has been approved by the methods of XRD, energy- dispersive analysis, UV-spectroscopy. The influence of the content of polymer matrix onto physico- mechanical properties of hydrogel has been studied.

Advanced treatment of low-pollution and poor biodegradability sewage by combined process

A system was developed for the treatment of low-pollution sewage with poor biodegradability and a low ratio of chemical oxygen demand (CODCr) to nitrate-nitrogen (COD/NO3−-N (C/N)) ratio to achieve high efficiency. This system combines the anaerobic-oxic (AO) process with the biological aerated filter (BAF) and introduces the Fenton advanced oxidation process. A pilot test system was established, and feasibility investigations were conducted using a continuous flow of 500 L/h. The results showed that the optimal conditions for removing nitrate from sewage were achieved with a C/N ratio of 5.5–6 and a hydraulic retention time (HRT) of 4 h. Under these conditions, the average nitrate removal efficiency was 83.36%, and the average concentration of total nitrogen (TN) in the effluent was reduced to 6.68 mg/L. Additionally, the Fenton oxidation treatment was effective in reducing the COD content of sewage, with an average removal efficiency of 82.47% and a decrease in CODCr from 55.24 mg/L to 9.68 mg/L. The combined process successfully met the stringent discharge standards after advanced treatment. Microbial community analysis revealed that the dominant genera in anoxic BAFs were Trichococcus, Comamonadaceae, Lentimicrobium, and Thauera, while the dominant genera in aerobic BAFs were mainly Acinetobacter, Thiothrix, Gemmobacter, and Caldilineaceae. The synergistic effect of various nitrifying and denitrifying bacteria in BAFs effectively removed nitrate from the sewage. Furthermore, GC-MS analysis indicated that the Fenton oxidation significantly reduced the concentration of refractory organic compounds in the sewage, including long-chain organic compounds and acrylic acid maleic acid copolymer (MA/AA). After upgrading and renovating the factory's sewage treatment facilities, the impact of the discharged effluent on the receiving drainage basin will be minimized.

Degradation of Polyacrylates by One-Pot Sequential Dehydrodecarboxylation and Ozonolysis

We establish a synthetically convenient method to degrade polyacrylate homopolymers. Carboxylic acids are installed along the polymer backbone by partial hydrolysis of the ester side chains, and then, in a one-pot sequential procedure, the carboxylic acids are converted into alkenes and oxidatively cleaved. This process enables the robustness and properties of polyacrylates to be maintained during their usable lifetime. The ability to tune the degree of degradation was demonstrated by varying the carboxylic acid content of the polymers. This method is compatible with a wide range of polymers prepared from vinyl monomers through copolymerization of acrylic acid with different monomers including acrylates, acrylamides, and styrenics.

PAA/TiO2@C composite hydrogels with hierarchical pore structures as high efficiency adsorbents for heavy metal ions and organic dyes removal

Hydrogel-based adsorbents have good application prospects in wastewater treatment, but their low porosity and specific surface area pose challenges to their practical applications. In this study, a porous hydrogel (T-PMADA) was prepared by copolymerization of acrylic acid (AA) and methacrylamide dopamine (MADA) in the presence of Ti3C2 MXene. The porous structure not only increased the specific surface area (44.2 m2/g) of the hydrogel, but also provided abundant active sites for the treatment of the pollutant, which led to the maximum adsorption capacity of T-PMADA hydrogel for Pb (II) and Cd (II) of 609.9 mg/g and 250.2 mg/g, respectively. In addition, the TiO2@C formed by the oxidation of Ti3C2 MXene also endows the hydrogel with the photocatalytic degradation ability for organic dyes. In treating the wastewater containing heavy metal ions and organic dyes, the T-PMADA hydrogel shows good treatment performance for heavy metal ions and organic dyes simultaneously. The above facts indicate that T-PMADA hydrogel can provide a brand-new strategy for water pollution treatment in complex polluted environments by its ability to treat heavy metals and organic dye pollutants.

Highly Sensitive Poly-N-isopropylacrylamide Microgel-based Electrochemical Biosensor for the Detection of SARS-COV-2 Spike Protein

ObjectiveLate 2019 witnessed the outbreak and widespread transmission of coronavirus disease 2019 (COVID-19), a new, highly contagious disease caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Consequently, considerable attention has been paid to the development of new diagnostic tools for the early detection of SARS-CoV-2. MethodsIn this study, a new poly-N-isopropylacrylamide microgel-based electrochemical sensor was explored to detect the SARS-CoV-2 spike protein (S protein) in human saliva. The microgel was composed of a copolymer of N-isopropylacrylamide and acrylic acid, and gold nanoparticles were encapsulated within the microgel through facile and economical fabrication. The electrochemical performance of the sensor was evaluated through differential pulse voltammetry. ResultsUnder optimal experimental conditions, the linear range of the sensor was 10−13–10−9 mg/mL, whereas the detection limit was 9.55 fg/mL. Furthermore, the S protein was instilled in artificial saliva as the infected human saliva model, and the sensing platform showed satisfactory detection capability. ConclusionThe sensing platform exhibited excellent specificity and sensitivity in detecting spike protein, indicating its potential application for the time-saving and inexpensive detection of SARS-CoV-2.

Anti-swelling conductive polyampholyte hydrogels via ionic complexations for underwater motion sensors and dynamic information storage

Swelling of hydrogels in aquatic environment is ubiquitous but unfavorable for underwater applications, which dramatically diminishes their mechanical properties. In this study, we report an anti-swelling conductive hydrogel based on a polyampholyte copolymer of acrylic acid and 1-butyl-3-vinylimidazolium bromide. The hydrogel exhibits high optical transparency, remarkable mechanical property, and good ionic conductivity. The anti-swelling property is achieved by balanced ionic complexation and hydrogen bonding with careful selection of the monomer feeding ratios. The conductive hydrogel is capable of sensing accurate and stable electro-mechanic responses under both small and large strains, making it a good candidate as strain sensors for monitoring human motions both in air and underwater. Furthermore, the unique material is patternable due to asymmetric swelling and shrinking kinetics, thus providing opportunities for the realization of dynamic information storage. It is believed that our design of anti-swelling conductive hydrogel can be a driving force towards broadening applications of hydrogel iontronics.

Molecularly Imprinted Polymer-Based Electrode for Tannic Acid Detection in Black Tea

The present study aims at developing a low-cost and reliable electrode based on the molecularly imprinted polymer (MIP) technology for the detection and quantification of tannic acid (TAN) in black tea samples. The material was synthesized using a copolymer of acrylic acid (AA) and ethylene glycol dimethacrylate (EGDMA), a cross-linker, on a graphite bed. The developed electrode material was characterized by ultraviolet–visible (UV–Vis) spectroscopy and scanning electron microscope (SEM). The performance of the electrode was evaluated by a three-electrode configuration using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The devised electrode (MIP_TAN) has shown a wide linear range of performance from 0.1 to 500 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{M}$ </tex-math></inline-formula> with a limit of detection (LOD) of 37 nM and evinced high repeatability, reproducibility, stability, and good selectivity. To predict the content of TAN, a partial least square regression (PLSR) model was developed utilizing DPV responses of the electrode and high-performance liquid chromatography (HPLC) as reference data. The prediction accuracy of PLSR was obtained as 96.315%. The electrode was examined on real samples of black tea, which produced satisfactory results.

The Use of Collagen Methacrylate in Actuating Polyethylene Glycol Diacrylate-Acrylic Acid Scaffolds for Muscle Regeneration.

After muscle loss or injury, skeletal muscle tissue has the ability to regenerate and return its function. However, large volume defects in skeletal muscle tissue pose a challenge to regenerate due to the absence of regenerative elements such as biophysical and biochemical cues, making the development of new treatments necessary. One potential solution is to utilize electroactive polymers that can change size or shape in response to an external electric field. Poly(ethylene glycol) diacrylate (PEGDA) is one such polymer, which holds great potential as a scaffold for muscle tissue regeneration due to its mechanical properties. In addition, the versatile chemistry of this polymer allows for the conjugation of new functional groups to enhance its electroactive properties and biocompatibility. Herein, we have developed an electroactive copolymer of PEGDA and acrylic acid (AA) in combination with collagen methacrylate (CMA) to promote cell adhesion and proliferation. The electroactive properties of the CMA + PEGDA:AA constructs were investigated through actuation studies. Furthermore, the biological properties of the hydrogel were investigated in a 14-day in vitro study to evaluate myosin light chain (MLC) expression and metabolic activity of C2C12 mouse myoblast cells. The addition of CMA improved some aspects of material bioactivity, such as MLC expression in C2C12 mouse myoblast cells. However, the incorporation of CMA in the PEGDA:AA hydrogels reduced the sample movement when placed under an electric field, possibly due to steric hindrance from the CMA. Further research is needed to optimize the use of CMA in combination with PEGDA:AA as a potential scaffold for skeletal muscle tissue engineering.

Effect of poly (acrylamide-co-acrylic acid salt) on anti-aging properties and adhesion between acrylonitrile butadiene rubber and polyester fabric

In this study, a multifunction polymeric adhesion promoter and anti-aging compound based on the triethanolamine salt of acrylamide acrylic acid copolymer (COS) was prepared and characterized using Fourier-transform infrared spectroscopy (FTIR). The impact of different COS contents on the tensile, adhesion, and thermal properties of NBR composite and NBR/PET sandwich was evaluated. The NBR composites containing COS displayed good retention of their mechanical properties with increasing thermal ageing time, while the composite without COS showed a decrease in its mechanical properties. The highest tensile strength (17.5 MPa with a retention value of 0.6%) after 7 days of thermal aging was recorded for NBR composite, which contains 5 phr (parts per hundred parts of rubber) of COS (COS 5), compared to NBR composite without COS (COS 0), which recorded 15.1 MPa with a retention value of -27.4%. In addition, the COS 5 composite displayed an improvement in peel strength of 16.4% compared to the COS 0. The results of the thermogarvemetric analysis (TGA) supported the anti-thermal ageing effect of COS, where the initial decomposition temperature (Ti) value increased by 11.7 and 9.3 °C, after addition of 5 and 10 phr of COS to NBR composite, respectively. In addition, the other thermogravemetric parameters investigated displayed a significant increase in their values, which confirms the improvement in thermal stability of NBR composite in the presence of COS. Also, the air permeability of the PET/NBR sandwich decreased by 80% after the addition of 7.5 phr of COS.