Ethylene-acrylic Acid Copolymer Research Articles

Enhancing asphalt-based waterproof materials for building cement substrates: Modifications, construction, and weathering resistance

Three distinct systems of asphalt-based waterproof material structures were designed for building cement substrates. These asphalt-based waterproof materials were modified using either Styrene Butadiene Rubber (SBR) or Ethylene Acrylic Acid Copolymer (EAA) along with various inorganic fillers. To enhance the adhesion between the waterproof materials and the cement substrate, the surface of the cement substrate was chemically treated with either γ-methacryloyloxypropyltrimethoxy silane (KH-570) or vinyltrimethoxy silane (SG-Si 171) through atomization spraying and infrared irradiation. The adhesion properties and debonding failure modes of waterproof materials for cement substrates were analyzed, and six groups of samples with relatively good adhesion properties were screened for further environmental aging tests. The samples were subjected to temperature fluctuations, water immersion, freeze-thaw cycles, thermal aging, acid, alkali, and salt, to identify favorable asphalt-based waterproof structure systems for five climate zones, acid rain-affected regions, and saline-alkali-affected regions in China. These results provide valuable insights for designing effective waterproof materials for different environments.

PH-responsive CuS/DSF/EL/PVP nanoplatform alleviates inflammatory bowel disease in mice via regulating gut immunity and microbiota

The clinical treatment of inflammatory bowel disease (IBD) is challenging. We developed copper sulfate (CuS)/disulfiram (DSF)/methacrylic acid-ethyl acrylate copolymer (EL)/polyvinylpyrrolidone (PVP) nanoplatform (CuS/DSF/EL/PVP) and evaluated its efficiency for treating IBD. After oral administration, the pH-sensitive EL protected the CuS/DSF/EL/PVP against degradation by acidic gastric juices. Once the colon was reached, EL was dissolved, releasing DSF and Cu2+. Further, the main in vivo metabolite of DSF can bind to Cu2+ and form copper (II) N, N-diethyldithiocarbamate (CuET), which significantly alleviated acute colitis in mice. Notably, CuS/DSF/EL/PVP outperformed CuS/EL/PVP and DSF/EL/PVP nanoplatforms in reducing colonic pathology and improving the secretion of inflammation-related cytokines (such as IL-4 and IL-10) in the colonic mucosa. RNA-seq analysis revealed that the nanoplatform reduced colonic inflammation and promoted intestinal mucosal repair by upregulating C-type lectin receptor (CLR)-related genes and signaling pathways. Furthermore, CuS/DSF/EL/PVP showed potential for improving colitis Th1/Th17 cells through innate immunity stimulation, down-regulation of inflammatory cytokines, and upregulation of anti-inflammatory cytokines. Additionally, the intervention with CuS/DSF/EL/PVP led to increased intestinal flora diversity, decreased Escherichia–Shigella abundance, and elevated levels of short-chain fatty acid (SCFA)-producing bacteria Prevotella, Lactobacillus, and Bifidobacterium, indicating their potential to modulate the dysregulated intestinal flora and suppress inflammation. Statement of SignificanceOur study introduces the CuS/DSF/EL/PVP nanoplatform as a therapeutic strategy for treating inflammatory bowel disease (IBD). This approach demonstrates significant efficacy in targeting the colon and alleviating acute colitis in mice. It uniquely modulates gut immunity and microbiota, exhibiting a notable impact on inflammation-related cytokines and promoting intestinal mucosal repair. The nanoplatform's ability to regulate gut flora diversity, combined with its cost-effective and scalable production, positions it as a potentially transformative treatment for IBD, offering new avenues for personalized medical interventions.

Effect of competitive interactions on the structure and properties of blends prepared from an industrial lignosulfonate polymer

To explore the possibility of applying lignin in practice, an industrial lignosulfonate (0–50 vol%) was blended with four ionomers. The concentrations of carboxyl and carboxylate groups were systematically varied in the ethylene-acrylic acid copolymers to study the competition of hydrogen and ionic bonds forming between the components. The mechanical properties of the blends were determined by tensile testing. The structure was investigated by scanning electron microscopy, while deformation and failure processes were studied by acoustic emission measurements and microscopy. Interfacial interactions were quantitatively characterized by analyzing local deformation processes and by evaluating the composition dependence of the tensile strength using appropriate models. Molecular dynamics simulations indicated that carboxylate groups preferably form clusters in the ionomer phase, consequently, the increasing degree of neutralization results in ionomers with more and more self-interactions of components deteriorating ionomer-lignin interactions. The novel combination of experiments, modeling, and simulation was done for the first time on such materials, and it pointed out that the role of hydrogen bonds is more critical in determining blend properties. Blends can be prepared for practical applications with a good combination of stiffness (0.8 GPa), tensile strength (22 MPa), and elongation-at-break (25 %) at 30 vol% lignosulfonate content and 33 % neutralization.

Detection and quantification of various microplastics in human endometrium based on laser direct infrared spectroscopy

The pollution of microplastics (MPs) has received widespread attention with the increasing usage of plastics in recent years. MPs could enter the human body and exist in the circulatory system. Endometrium, with rich blood vessels, acts as an essential role in human health and female fertility. However, there is no study reporting the MPs exposure in human endometrium. We collected the endometrium samples to detect the presence of MPs qualitatively and quantitatively via laser direct infrared. We found that there was a total of 13 types of MPs existing in the collected samples, among which 6 special types of MPs were with both high abundance and high detection rate. The abundance of these MPs ranged from 0 to 117 particles/100 mg, with a median abundance of 21 particles/100 mg. Most detected MPs, accounting for 88.35 %, were in small size (20–100 μm). Among small-size MPs, ethylene-acrylic acid copolymer ranked first while polyethylene accounted for the largest proportion among large-size MPs (100–500 μm). Correlation analysis indicated there was no significant relationship between age and MP abundance or BMI and MP abundance. We also designed a questionnaire to investigate lifestyle and daily habits, aiming at revealing the potential relationship between MP exposure and living habits. We discovered that some drinking habits and chewing gum were significantly correlated with a higher level of MP exposure. For the first time, we identified the presence of MPs in human endometrium and clarified the potential connections between MP exposure and lifestyle. Further studies are still necessary to explore more underlying information.

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

Processability evaluation of multiparticulate units prepared by selective laser sintering using the SeDeM Expert System approach

3D printing in dosage forms fabrication is in the focus of researchers, however, the attempts in multiparticulate units (MPUs) preparation are scarce. The aim of this study was to fabricate different size MPUs by selective laser sintering (SLS), using different polymers, and investigate their processability based on the SeDeM Expert System approach.MPUs (1- or 2-mm size) were prepared with model drug (ibuprofen or caffeine), polymer (poly(ethylene)oxide (PEO), ethyl cellulose (EC) or methacrylic acid-ethyl acrylate copolymer (MA-EA)) and printing aid. Comprehensive sample characterization was performed and experimentally obtained parameters were mathematically transformed and evaluated using the SeDeM Expert System framework. The obtained samples exhibited irregular shape, despite the spherical printing object design. Polymer incorporated notably affected MPUs properties.The obtained samples exhibited low bulk density, good flowability-, as well as stability-related parameters, which indicated their suitability for filling into capsules or sachets. Low density values implied that compressibility enhancing excipients may be required for MPUs incorporation in tablets. Samples containing EC and MA-EA were found suitable for compression, due to high compacts tensile strength. The obtained results indicate that SeDeM Expert System may extended from powder compressibility evaluation tool to framework facilitating powders/multiparticulate units processing.

A phase change supramolecular assembly with a rapid self-healing behavior via thermally actuated reversible associations

Phase change materials (PCMs) have demonstrated great potential and vast development prospects in many cutting-edge fields. However, the design and development of smart PCMs with rapid self-healing abilities, and with a reversible switching between rigidity and flexibility, remain challenge. We have here described a strategy that utilizes dynamic carboxylate/zinc ions interactions to achieve this objective. The phase change supramolecular (EAA-Zn-SA) was developed from a commercial, inexpensive and nontoxic ethylene acrylic acid copolymer (EAA) and stearic acid (SA) via crosslinking by zinc ions. It had an excellent leakage-proof, comparable energy storage capacity (130.8 J/g) and could be directly charged by using solar irradiation. As the dynamic carboxylate/zinc ions interactions are temperature sensitive, the designed supramolecular also possessed reversible switching between rigidity and flexibility upon heating or cooling. As a result, the EAA-Zn-SA did not only offer a rapid self-healing behavior, but was also available for orthopedic immobilization and thermal therapy of the human body. This strategy may open a brand-new door for the preparation of a healable phase change supramolecular and enlarge the practical application of PCMs.

Adhesively bonding a reusable PZT transducer for structural health monitoring (SHM) with an ethylene-acrylic acid copolymer adhesive

A novel approach to bonding a piezoelectric lead zirconate titanate (PZT) transducer on a structure for health monitoring was developed to replace the traditional method of bonding PZT permanently. Several experiments demonstrated the feasibility of a reusable PZT transducer based on the adhesive film made using ethylene-acrylic acid copolymer (EAA). Additionally, the adhesion performance of using EAA for bonding PZT at different temperatures and the effect of heating temperature on reusable PZT transducer removal from the test structure was investigated. The effect of adhesive thickness on the mechanical property and the performance of PZT has also been explained. Experimental results showed that the optimized heating temperature of the adhesive film was around 140 °C due to the stability of PZT being sensitive to high temperature and the ease of removing PZT from the test structure without damage. An analysis of the varying thickness of the adhesive layer on PZT performance indicated that the amplitude of Lamb wave signals changed with adhesive thickness, increasing with greater adhesive thickness. Therefore, the adhesive layer made using EAA provides a new approach to conducting Lamb wave-based structural health monitoring.

ASD Formation Prior to Material Characterization as Key Parameter for Accurate Measurements and Subsequent Process Simulation for Hot-Melt Extrusion

Process simulation facilitates scale-up of hot-melt extrusion (HME) and enhances proper understanding of the underlying critical process parameters. However, performing numeric simulations requires profound knowledge of the employed materials’ properties. For example, an accurate description of the compounds’ melt rheology is paramount for proper simulations. Hence, sample preparation needs to be optimized to yield results as predictive as possible. To identify the optimal preparation method for small amplitude oscillatory shear (SAOS) rheological measurements, binary mixtures of hydroxypropylmethylcellulose acetate succinate or methacrylic acid ethyl acrylate copolymer (Eudragit L100-55) together with the model drugs celecoxib and ketoconazole were prepared. The physical powder mixtures were introduced into the SAOS as a compressed tablet or a disk prepared via vacuum compression molding (VCM). Simulations with the derived parameters were conducted and compared to lab-scale extrusion trials. VCM was identified as the ideal preparation method resulting in the highest similarity between simulated and experimental values, while simulation based on conventional powder-based methods insufficiently described the HME process.

Optimization of ethylene acrylic acid and low density polyethylene blend in tie-layer

Ethylene acrylic acid copolymer (EAA) is widely used as tie-layer in multilayer film structures containing aluminum foil. EAA provides adhesion between the foil and rest of the film structure. It can be used alone or as a blend with low density polyethylene (LDPE), ordinarily between 20 and 50%. However, blending EAA and LDPE does not always produce desirable results. From time to time, a clear film becomes hazy as the EAA content is increased. At the same time, the adhesive strength to foil decreases. This study focuses on elucidating the mechanism behind the high haze and poor adhesion associated with EAA/LDPE blends and on determining factors that can optimize blend performance. The results from this study indicate that immiscibility, not viscosity mismatch, is the dominant factor affecting EAA/LDPE blends. In general, EAA with low acid content is more compatible with LDPE than EAA with high acid content. Processing parameters, such as extruder RPM and melt temperature, can also be selectively used to improve the blend haze or layer adhesion.

Trojan pH-Sensitive Polymer Particles Produced in a Continuous-Flow Capillary Microfluidic Device Using Water-in-Oil-in-Water Double-Emulsion Droplets.

A facile and robust microfluidic method to produce nanoparticle-in-microparticle systems (Trojan systems) is reported as a delivery vector for the oral administration of active pharmaceutical ingredients. The microfluidic system is based on two coaxial capillaries that produce monodisperse water-in-oil-in-water (W/O/W) double emulsions in a highly controlled fashion with precise control over the resulting particle structure, including the core and shell dimensions. The influence of the three phase flow rates, pH and drying process on the formation and overall size is evaluated. These droplets are then used as templates for the production of pH-sensitive Trojan microparticles after solvent evaporation. The shell of Trojan microparticles is made of Eudragit®, a methacrylic acid-ethyl acrylate copolymer that would enable the Trojan microparticle payload to first pass through the stomach without being degraded and then dissolve in the intestinal fluid, releasing the inner payload. The synthesis of the pH-sensitive Trojan microparticles was also compared with a conventional batch production method. The payloads considered in this work were different in nature: (1) fluorescein, to validate the feasibility of the polymeric shell to protect the payload under gastric pH; (2) poly(D,L-lactic acid/glycolic acid)-PLGA nanoparticles loaded with the antibiotic rifampicin. These PLGA nanoparticles were produced also using a microfluidic continuous process and (3) PLGA nanoparticles loaded with Au nanoparticles to trace the PLGA formulation under different environments (gastric and intestinal), and to assess whether active pharmaceutical ingredient (API) encapsulation in PLGA is due efficiently. We further showed that Trojan microparticles released the embedded PLGA nanoparticles in contact with suitable media, as confirmed by electron microscopy. Finally, the results show the possibility of developing Trojan microparticles in a continuous manner with the ability to deliver therapeutic nanoparticles in the gastrointestinal tract.

Boost of solubility and supersaturation of celecoxib via synergistic interactions of methacrylic acid-ethyl acrylate copolymer (1:1) and hydroxypropyl cellulose in ternary amorphous solid dispersions

A current trend in the development of amorphous solid dispersions (ASDs) is the combination of two polymers for synergistic enhancement in supersaturation of poorly soluble drugs. We investigated the supersaturation potential of celecoxib (CXB) using combinations of methacrylic acid-ethyl acrylate copolymer (1:1) (EL 100–55) and hydroxypropyl cellulose (HPC) SSL. Initially, the supersaturation potential of single polymers and combinations in various ratios was assessed. While EL 100–55 and HPC SSL alone showed limited potential in solubility enhancement of CXB the combination of both polymers led to a boost of CXB solubility, whereby most promising results were obtained using a 50:50 polymer ratio. Binary and ternary CXB ASDs (10% drug load) were prepared via vacuum compressing molding (VCM) and hot melt extrusion (HME). ASDs were studied by exploring the miscibility and intermolecular interactions and tested for their dissolution performance. HPC SSL was identified to be a suitable precipitation inhibitor when added to a fast dissolving CXB: EL 100–55 ASD. Ternary ASDs showed even further dissolution improvement, when processed by HME. The combination of heat and shear stress led to a homogeneous and intimate mixture of EL 100–55 and HPC SSL, resulting in formation of synergistic interactions with pronounced impact on CXB supersaturation.

Amidation of Polyethylene-Acrylic Acid Copolymer as Pour Point Depressants for Waxy Crude Oils

The present work aims to provide amine-modified polyethylene-acrylic acid (PEAA) copolymers as a pour point depressant (PPD) that will be evaluated for lower pour point of crude oil. For this, PEAA was amidated with butylamine and octadecylamine in the presence of xylene as a solvent at 150 °C for 10 hours to obtain copolymers PEAA/ODA and PEAA/BA. The copolymers were modified by amidation using the carboxyl groups of an ethylene-acrylic acid copolymer as reaction sites in reactions with RNH2. The resulting copoly-mers were purified and analyzed by FTIR spectroscopy. The modified PEAA copolymers were evaluated for their effectiveness as depressants for crude oils by pour point measurements at 50 ppm, 100 ppm and 200 ppm and rheological measurements at 100 ppm. The pour point measurements of the crude oil showed that octadecylamine-modified PEAA copolymer performed better than butylamine-modified and unmodified PEAA copolymer. The effectiveness of the modified copolymers compared to unmodified PEAA can be ex-plained by the polarity of the monoalkylamide groups in the peripheral substituents along the copolymer backbone, which plays a crucial role in preventing the agglomeration of wax crystals in crude oil.

Development, Characterization, Optimization, and In Vivo Evaluation of Methacrylic Acid-Ethyl Acrylate Copolymer Nanoparticles Loaded with Glibenclamide in Diabetic Rats for Oral Administration.

The methacrylic acid–ethyl acrylate copolymer nanoparticles were prepared using the solvent displacement method. The independent variables were the drug/polymer ratio, surfactant concentration, Polioxyl 40 hydrogenated castor oil, the added water volume, time, and stirring speed, while size, PDI, zeta potential, and encapsulation efficiency were the response variables analyzed. A design of screening experiments was carried out to subsequently perform the optimization of the nanoparticle preparation process. The optimal formulation was characterized through the dependent variables size, PDI, zeta potential, encapsulation efficiency and drug release profiles. In vivo tests were performed in Wistar rats previously induced with diabetes by administration of streptozotocin. Once hyperglycemia was determined in rats, a suspension of nanoparticles loaded with glibenclamide was administered to them while the other group was administered with tablets of glibenclamide. The optimal nanoparticle formulation obtained a size of 18.98 +/− 9.14 nm with a PDI of 0.37085 +/− 0.014 and a zeta potential of −13.7125 +/− 1.82 mV; the encapsulation efficiency was of 44.5%. The in vivo model demonstrated a significant effect (p < 0.05) between the group administered with nanoparticles loaded with glibenclamide and the group administered with tablets compared to the group of untreated individuals.

Ultra-high flexibility amidoximated ethylene acrylic acid copolymer film synthesized by the mixed melting method for uranium adsorption from simulated seawater

If U(VI) in seawater (unconventional uranium resource) can be extracted efficiently, it can provide important supplies and guarantees for the stable development of nuclear power. In this study, a mixing melting method without condensation agent was proposed to prepare ultra-high flexibility and different proportions DAMN modified EAA resin film (EAA-DAMN) through the condensation reaction between -COOH and -NH2 and the uniform mixing of liquid EAA and DAMN. In addition, the dense film structure and -CN of EAA-DAMN were transformed into multiple pores structure and amidoxime groups of the amidoximated EAA (AO-EAA) by amidoxime reaction. The AO-EAA-3 showed the most excellent adsorption performance (qe=146.40 mg g−1) at pH = 5, which was 2.33 times that of EAA. Moreover, a hypothesis was proposed for the first time that -NH2 in the material could combine with H+ ionized by water to form -NH3+, and then adsorbed NO3- in the solution through electrostatic attraction, and O element from NO3- adsorbed on the surface and N-O from amidoxime groups of material as the adsorption active sites performed coordination with U(VI), thereby improving the adsorption performance of AO-EAA.

Diffusion of nitrogen gas through polyethylene based films

Polyethylene-based films can be used as sealant materials at room temperature in packaging applications. They can be also melted and sealed with glass, acting as sealant material in solar cells. The polyethylene-based polymers investigated in this paper are a linear low-density polyethylene modified with maleic anhydride (or PE-MAH), and an ethylene acrylic acid copolymer (or EMAA). Measurements of nitrogen gas diffusion coefficient (D) have been performed at three different temperatures ranging between 23°C and 32°C. The experimental apparatus used to measure the diffusion coefficients is original compared with other commonly used. The obtained D results have been correlated with the polymeric structure and morphology by means of differential scanning calorimetry (DSC), thermogravimetric-analyses (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM) experimental analyses. Furthermore, D-coefficients are compared with the literature data of other polyethylenes with different structural organization (HDPE, LLDPE, and LDPE). The thermal activation energy is evaluated for the two polymers. Arrhenius plot has been used to calculate the activation energies of both polymers and to predict the D-coefficient at other temperatures, close to these analyzed.

Ultra-high mechanical property and multi-layer porous structure of amidoximation ethylene-acrylic acid copolymer balls for efficient and selective uranium adsorption from radioactive wastewater

Adsorption uranium [U(VI)] from U-containing radioactive wastewater (URW) is a critical strategy for solving the resource shortage and environmental pollution in pace with the sustainable development of nuclear energy. However, the URW universally exhibits acidity and contains co-existing metal ions with high concentration. Herein, the amidoximation ethylene-acrylic acid copolymer balls (EAA-AO) with aciduric and super-high mechanical property were successfully synthesized through grafting diaminomaleonitrile and further treatment of amidoximation. Significantly, the mechanical properties of EAA-AO were not affected by the grafting process and maintained super-high mechanical properties. Furthermore, the –NH2 and unreacted –CN groups in diaminomaleonitrile adjusted the pKa to make the optimal pH be 4. In addition, the microstructure of EAA-AO was transformed from the original dense to multi-layer porous structure, which promoted the mass transfer process and the contact between uranyl ions (UO22+) and internal adsorption active sites. The adsorption capacity of EAA-AO was about 1.78 times that of EAA at pH = 4, and the adsorption capacity for U(VI) was about 8.17 times that of Ba2+ with the second highest adsorption capacity. Therefore, the EAA-AO exhibited ultra-high adsorption performance (qe = 3.196 mg g−1) in the artificial radioactive wastewater, laying a good foundation for subsequent large-scale industrial adsorption of U(VI) in nuclear industrial wastewater.

Polymerization Mechanism and Kinetics of Preparation of Methacrylic Acid-Ethyl Acrylate Copolymer Emulsion Reverse Demulsifier

It was shown that methacrylic acid-ethyl acrylate copolymer (P(EA-MAA)) emulsion has a good reverse demulsification performance for treatment of water produced in oilfields. Its polymerization mechanism, kinetics and demulsification mechanism are important for its application and scale-up production. Therefore, they were studied in the research described in this paper. It was found that the demulsification mechanism of P(EA-MAA) was related to the ion compositions of the produced water and the conformation change of P(EA-MAA) when it was dissolved in the produced water. The distributions of monomer and surfactant before the polymerization were investigated and we found that there were both homogeneous nucleation and micellar nucleation during the first stage of emulsion polymerization. The relationships among the polymerization rate (Rp), monomer concentration ([M]), initiator concentration ([I]) and surfactant concentration ([S]) were studied. The emulsion copolymerization kinetic equation was Rp∝[M]0.64 [I]0.68 [S]0.41, which is related with the nucleation mechanism of the polymerization mechanism. In addition, the activation energy was 34.50 kJ/mol.

Strengthening effect of mullins effect under tearing mode and its reversibility for zinc dimethacrylate-reinforced thermoplastic vulcanizates based on ethylene-acrylic acid copolymer/nitrile-butadiene rubber blends

ABSTRACT Thermoplastic vulcanizates (TPVs) based on ethylene-acrylic acid copolymer (EAA)/nitrile-butadiene rubber (NBR) and zinc dimethacrylate (ZDMA) reinforced EAA/NBR blends were prepared by dynamical vulcanization, the mechanical properties and Mullins effect of the TPVs under tearing mode were investigated systematically. Experimental results indicated that the increasing EAA dosage in the EAA/NBR TPVs and the incorporation of ZDMA in NBR phase of TPVs could all lead to the increase of tear strength. The Mullins effect of EAA/NBR and EAA/NBR/ZDMA TPVs could be observed obviously under tearing mode, while it was hardly to obverse in that of static NBR vulcanizate during the cyclic deformation.

Effect of ethylene acrylic acid co-polymer coating on bending and thermal properties of cotton fabrics

Bleached cotton fabric and a water-based polymer coating solution made from ethylene acrylic acid co-polymer which is multifunctional polymer material is used in this experimental study to increase the bending and thermal properties of cotton fabrics. Roller coating and Exhaust methods is used to apply ethylene acrylic acid co-polymer solution on the cotton fabric surface. The coated fabric surface is then cured and dried at a temperature of 60–90 °C using a laboratory oven. The developed fabric samples are then taken for testing for its bending and thermal properties using a fabric stiffness tester and DSC thermal analyzer. The chemical composition and its chemical group finger print analysis is also ascertained using FTIR spectra. The fabric stiffness results of coated fabrics show increased bending properties and the thermal property results from DSC and plotted graphs prove its robustness and resistance to heat. However, Roller coating method seems to be more efficient than exhaust method with respect to the application method employed for coating ethylene acrylic acid co-polymer.