Polyester Polymer Research Articles

Study of the Flexural Resistance of Unsaturated Polyester Composite Reinforced by Finely Ground Sugarcane Bagasse Fiber for Light Construction

One of the polymer materials widely used in the field of engineering construction to be a candidate to replace metal materials is unsaturated polyester. This reason is because this material has many advantages such as low mass, ease of shape and resistance to moisture. However, this material still has many shortcomings, including low mechanical strength and easy cracking. Unsaturated polyester polymer material is widely used as a matrix for making composite materials for engineering fields such as vehicles and ship hulls. This research studies the flexural strength of composite materials from unsaturated polyester reinforced with finely ground sugarcane fibre. From the results of flexural strength testing, it is known that there is a tendency towards the variable addition of finely ground sugarcane fibre. increases from 10% to 20%, and after 20% the bending stress value tends to decrease. The maximum flexural stress value was obtained by adding a percentage of finely ground sugarcane fibre. with a percentage of 20% 102.32 MPa, this value can increase the maximum flexural stress value of pure polyester by 42.52 MPa, showing an increase of 249.63%

Microplastics in the digestive tract of an endangered cetacean of the Southwest Atlantic Ocean: The franciscana dolphin

In this study, we investigated for the first time anthropogenic microparticles in the franciscana dolphin Pontoporia blainvillei, the most endangered cetacean of the Southwest Atlantic Ocean. The intestinal content of the proximal and distal sections, and wall tissues of the proximal section of ten female dolphins collected during 2013–2023 were analyzed. All samples contained anthropogenic particles (%FO = 100). Fibers were the most abundant shape (99 %). Micro-Raman and micro-FTIR spectroscopies revealed the presence of polyester, polypropylene, acrylic, polyethylene, and semi-synthetic cotton polymers. Manufactured pigments such as reactive blue 238, Indigo 3600, and diarylide azo pigment (yellow 152) were also detected. We observed variations in the color and types of polymers present in the different sections of the intestine and within the wall tissue, suggesting a differential microplastic absorption. These findings confirm both the presence and absorption of microplastics in the intestines from franciscana dolphins.

Synthesis of long-chain polyester polymers and their properties as crude oil pour point depressant.

Using acrylic acid advanced ester and styrene as raw materials, the long-chain polyester polymer, polyacrylic acid advanced ester-styrene pour point depressant (P-PPD), was synthesized by molecular design, and its structure was characterized by infrared spectroscopy and nuclear magnetic resonance. In addition, this study experimentally investigated the effect of P-PPD on the phase equilibrium and induction time of natural gas hydrate inhibitors in deionized water (DW) and crude oil/water (O/W) systems, respectively. Polyvinylpyrrolidone (PVP) and mono ethylene glycol (EG) were selected as representatives of kinetic hydrate inhibitor (KHIs) and thermodynamic hydrate inhibitor (THIs), respectively. The results exhibit that P-PPD played a sight role in the phase equilibrium of hydrate, while the addition of P-PPD significantly prolonged the induction time of methane hydrate both in O/W + PVP, OW + EG and O/W + PVP + EG system, indicating that the addition of as-synthesized PPD has a synergistic inhibition effect on the nucleation ability of methane hydrate and can prevent hydrate from formatting during oil and gas transport process, and thus guarantee the flow assurance. The findings of this work will provide a data reference for the hybrid use of hydrate inhibitors and pour point depressants in oil and gas transport.

Influence of Polyester and Acrylic Polymer Coatings on the Mechanical, Physical and Microstructural Characteristics of Recycled Aggregate Concrete

Influence of Polyester and Acrylic Polymer Coatings on the Mechanical, Physical and Microstructural Characteristics of Recycled Aggregate Concrete

Improved Energy Density at High Temperatures of FPE Dielectrics by Extreme Low Loading of CQDs.

Electrostatic capacitors, with the advantages of high-power density, fast charging-discharging, and outstanding cyclic stability, have become important energy storage devices for modern power electronics. However, the insulation performance of the dielectrics in capacitors will significantly deteriorate under the conditions of high temperatures and electric fields, resulting in limited capacitive performance. In this paper, we report a method to improve the high-temperature energy storage performance of a polymer dielectric for capacitors by incorporating an extremely low loading of 0.5 wt% carbon quantum dots (CQDs) into a fluorene polyester (FPE) polymer. CQDs possess a high electron affinity energy, enabling them to capture migrating carriers and exhibit a unique Coulomb-blocking effect to scatter electrons, thereby restricting electron migration. As a result, the breakdown strength and energy storage properties of the CQD/FPE nanocomposites are significantly enhanced. For instance, the energy density of 0.5 wt% CQD/FPE nanocomposites at room temperature, with an efficiency (η) exceeding 90%, reached 9.6 J/cm3. At the discharge energy density of 0.5 wt%, the CQD/FPE nanocomposites remained at 4.53 J/cm3 with an efficiency (η) exceeding 90% at 150 °C, which surpasses lots of reported results.

Nano-SiO2/polyurethane modified unsaturated polyester resin mortar for thin layer repairing on airport pavement

This paper introduces a novel toughened polymer mortar designed for runway repair, featuring outstanding impact resistance, high strength, and cost-effectiveness. To augment the toughness of unsaturated polyester (UP) polymer mortar, nano-SiO2 and polyurethane (PU) were incorporated. Firstly, the optimal dosages of nano-SiO2 and PU were determined through tensile test and impact test. Then, the modification mechanism of nano-SiO2/PU on UP resin was explored by microscopic image technology. In addition, the compression, flexural, fluidity, flexural bond strength and construction time tests were carried out to determine the optimal formula of nano-SiO2/PU modified UP resin mortar. Finally, the durability, impact resistance, impermeability resistance, skid resistance, and interlayer bond strength of modified UP resin mortar were studied and compared with those of pure UP resin mortar and epoxy (EP) resin mortar. Results show that the optimum proportion by mass for nano-SiO2/polyurethane modified UP resin is, UP resin: PU: dibutyltin dilaurate: nano-SiO2: initiator: accelerator: diluent: plasticizer = 1: 0.1: 0.002: 0.01: 0.01: 0.01:0.15:0.01. Furthermore, the mass proportion of modified UP resin to aggregate is 1: 1.2. In nano-SiO2/PU modification of UP resin, the -NCO groups of PU have been involved in chemical interaction with the -OH group of UP, while nano-SiO2 and UP resin are blended physically only. Compared with pure UP resin mortar, the nano-SiO2/PU modified UP resin mortar exhibited a 44% reduction in shrinkage rate, approximately 20% less corrosion loss, a 32% decrease in freeze-thaw loss, a 37% improvement in impact resistance, and increased shear bonding strength, flexural bonding strength, and tensile bonding strength by 44%, 33%, and 47%, respectively. Although the modified UP resin mortar demonstrated slightly lower performance in terms of dry shrinkage, corrosion resistance, skid resistance, and tensile bond strength compared to EP resin mortar, its freeze-thaw durability, impact resistance, flexural bond strength, and shear bond strength surpassed those of EP resin mortar. All three materials exhibited excellent impermeability. Leveraging the advantages of PU and nano-SiO2, the modified UP resin presents a promising repair material for airport pavement with enhanced toughness, high stability, and reduced cost.

Constructing lithiophilic sites–rich artificial solid electrolyte interphase to enable dendrite−free and corrosion−free lithium–sulfur batteries

An artificial solid electrolyte interphase (SEI) with lithiophilic sites and chemical bonds anchoring lithium polysulfides (LiPSs) has been developed as a potential solution to protect the lithium (Li) metal anode of Lithium−sulfur (Li–S) batteries. This strategy aims to guide consistent Li deposition and relieve lithium corrosion. Herein, the evolution process of lithiophilic sites based on aluminum fluoride (AlF3) in an artificial SEI is disclosed in Li–S batteries with metal−based lithiophilic sites. The polyester polymer (PMMA and PPC)/AlF3 artificial SEI (MPAF−SEI) was homogeneously anchored on Li anode by in−situ polymerization. The conversion of AlF3 into Li–Al and LiF lithiophilic sites effectively reduce the Li nucleation overpotential and prevents the formation of Li dendrites. At the same time, the polymer can anchor LiPSs by chemical bonds and prevents Li corrosion. The optimized MPAF−SEI protected Li demonstrates excellent stability for over 3000 h at a capacity of 1 mAh cm−2 in Li || Li symmetric cells. The Li–S battery with low N/P (4) exhibits a capacity of 532.6 mAh g −1 over 300 cycles lifespan at 0.5C.

Method of Increasing the Fracture Toughness of Unsaturated Polyester with the Addition of Vinyl Ester as a Material for Automotive Body

Unsaturated polyester is the polymer material most widely used for matrix composites in the field of construction engineering, including for ships, automotive components and other engineering fields. The weakness of this polymer is that it is brittle and brittle and is unable to withstand cracking loads due to having cross-linked molecules that easily link together. The study to improve it was mixing with vinyl ester which succeeded in making the polyester crack resistant which was tested using a CTM machine and the fracture was observed using an SEM microscope. The test results showed that the polyester polymer mixed with 30% vinyl ester showed the highest increase in fracture strength, which was equal to K<sub>1c</sub> = 1.67 N.mm<sup>0.5</sup> compared to pure polyester, only K<sub>1c</sub> = 0.77 N.mm<sup>0.5</sup> can increase (216 %). Increasing the mixture content of 30% vinyl ester in polyester will change the brittle nature of unsaturated polyester to become more resilient because the vinyl ester molecules break the bonds of the polyester molecular chains.

Most recently developed polyester polymer alloy dialyzer: A new medium cut-off membrane?

New versions of the polyester polymer alloy (PEPA) membrane have appeared over the years, with increases in both the pore size and the amount of polyvinylpyrrolidone (PVP) to optimize hydrophilicity performance. This study aimed to assess the efficacy of the most recently developed PEPA dialyzer, the FDY series, in hemodialysis (HD) modality in terms of uremic toxin removal and albumin loss and to compare it with that of several high-flux dialyzers currently used in HD and post-dilution hemodiafiltration (HDF) treatments. A prospective study was carried out in 21 patients. All patients underwent six dialysis sessions with the same routine dialysis parameters; only the dialyzer and/or the dialysis modality varied: FX80 in HD, FDY 180 in HD, Clearum HS17 in HDF, Elisio 19H in HDF, Vitapes 180 in HDF, and FX80 in post-dilution HDF. The reduction ratios (RR) of urea, creatinine, ß2 -microglobulin, myoglobin, κFLC, prolactin, α1 -microglobulin, α1 -acid glycoprotein, λFLC, and albumin were compared intraindividually. Dialysate albumin loss was also measured. Both membranes FDY and FX80 are high-flux dialyzers and are applied here in high-flux HD. The average RR of β2 -microglobulin was slightly lower in the two HD treatments than in the HDF treatments. Comparison of dialysis treatments revealed that the PEPA FDY dialyzer in the HD modality was more effective than the FX80 dialyzer in high-flux HD and was as effective as post-dilution HDF, especially in terms of myoglobin, κFLC, prolactin, α1 -microglobulin, and λFLC RRs. The FDY treatments obtained similar albumin RR in blood and slightly higher dialysate albumin loss, although the values were clinically acceptable. The most recently developed PEPA dialyzers in the HD modality were as effective as all treatments in the HDF modality and were clearly superior to high-flux helixone HD treatment. These results confirm that this dialyzer should be categorized within the medium cut-off (MCO) membrane classification.

The Study of the Glass Fiber Surface Treatment Effect on the Base Strength Characteristics of the Composite Material

This article examines the impact of surface treatment of glass fibers on the strength of a composite material with an unsaturated polyester polymer matrix reinforced with glass fibers. The strength tests conducted include tensile, bending, and impact strength tests, as well as weight loss measurements. The research was conducted in two stages: in the first stage, the time was kept constant while the fibers were treated with varying concentrations of an alkaline NaOH solution; in the second stage, the concentration was fixed and the variable parameter was the treatment time. The results of the study indicate that surface treatment of glass fibers significantly improves their adhesion to the matrix materials, resulting in improved strength test results for the composite samples. The impact resistance, bending resistance, and tensile strength values all increased compared to the reference samples. However, certain changes in the individual parameters of fiber processing led to a slight decrease in tensile strength when it fell below the reference values. Additionally, it was observed that as the concentration of the solution and treatment time increased, the weight of the fibers decreased.

Tapered Optical Fiber Coated with a Polyester Polymer as a Curvature Sensor

Tapered Optical Fiber Coated with a Polyester Polymer as a Curvature Sensor

Comprehensive review of materials, applications, and future innovations in biodegradable esophageal stents.

Esophageal stricture (ES) results from benign and malignant conditions, such as uncontrolled gastroesophageal reflux disease (GERD) and esophageal neoplasms. Upper gastrointestinal endoscopy is the preferred diagnostic approach for ES and its underlying causes. Stent insertion using an endoscope is a prevalent method for alleviating or treating ES. Nevertheless, the widely used self-expandable metal stents (SEMS) and self-expandable plastic stents (SEPS) can result in complications such as migration and restenosis. Furthermore, they necessitate secondary extraction in cases of benign esophageal stricture (BES), rendering them unsatisfactory for clinical requirements. Over the past 3decades, significant attention has been devoted to biodegradable materials, including synthetic polyester polymers and magnesium-based alloys, owing to their exceptional biocompatibility and biodegradability while addressing the challenges associated with recurring procedures after BES resolves. Novel esophageal stents have been developed and are undergoing experimental and clinical trials. Drug-eluting stents (DES) with drug-loading and drug-releasing capabilities are currently a research focal point, offering more efficient and precise ES treatments. Functional innovations have been investigated to optimize stent performance, including unidirectional drug-release and anti-migration features. Emerging manufacturing technologies such as three-dimensional (3D) printing and new biodegradable materials such as hydrogels have also contributed to the innovation of esophageal stents. The ultimate objective of the research and development of these materials is their clinical application in the treatment of ES and other benign conditions and the palliative treatment of malignant esophageal stricture (MES). This review aimed to offer a comprehensive overview of current biodegradable esophageal stent materials and their applications, highlight current research limitations and innovations, and offer insights into future development priorities and directions.

Machine learning‐based prediction of mechanical and thermal properties of nickel/cobalt/ferrous and dried leaves fiber‐reinforced polymer hybrid composites

AbstractDried leaves are the outstanding origin of cellulosic plant matter, and it is securing reputation as a renewable resource. Dried leaves fiber is suggested to possess the capability to substitute synthetic fibers in polymer laminates as a reinforcing component. The novelty of the present study reveals the effect of dried leaves fiber, cobalt, nickel, and ferrous reinforcement on the physical, mechanical, and thermal characteristics of epoxy, vinyl‐ester, and polyester polymers using artificial neural network (ANN) technique. These composites were fabricated using ultrasonication bath‐assisted wet layup method under ambient condition. The outcomes of this research exhibit that the dried leaves‐cobalt fillers reinforced in all three polymers possess higher mechanical and thermal stability characteristics when compared with other samples. The reason may be assigned to producing novel hydroxyl functional groups and strong interfacial bonding of fillers within the matrix as observed from Fourier‐transform infrared (FTIR) spectra and scanning electron microscope (SEM) micrographs, respectively. Moreover, as observed from the thermogravimetric analysis, the dried leaves‐ferrous filler‐reinforced polymer hybrid composites provided higher thermal stability. Statistical analysis was performed using the one‐way ANOVA technique and found that outcomes were significant statistically under the confidence level of 95%. Hence, this investigation not only emphasize the significance of investigating new polymer composites but also highlight the benefits of engaging advanced modeling to forecast the material characteristics precisely.Highlights Dried leaves and cobalt/nickel/ferrous are applied reinforcement to polymers. Composites fabricated using ultrasonication bath‐assisted wet layup technique. LM Algorithm‐based ANN selected for predicting the best composite. Higher mechanical and thermal stability with dried leaves‐cobalt filler. One‐way ANOVA proved statistically significant within the material properties.

The Effect of Surface Treatment/Polymer Type on Formation of 3D-Boron Nitride Foams

In this study, the use of boron nitride (BN) foam composites as adsorbents in wastewater treatment using polyvinyl alcohol (PVA), polyvinyl butyral (PVB) and polyester (PE) polymers has been investigated. BN powder has been functionalized by Hummer’s and sodium hydroxide (NaOH) methods to facilitate BN binding with the polymer. Fourier Transform Infrared (FT-IR) results show that hydroxyl (-OH) groups are effectively bounded to the BN structure. Scanning Electron Microscope (SEM) observation demonstrated the 3D interconnected porous structure of the obtained BN foams using different polymers. It is observed that BN and polymer interaction is better in foams formed with PVA and PVB compared to PE polymers. PVA and PVB structure shows a bridge property to link the layers so that a porous network structure is formed. It has been determined that the foam composite modified with Hummer’s method and using PVB as a polymer (h-BN-PVB-H) reaches an adsorption capacity of 8.843 mg/g in 44 hours and provides approximately 18% Crystal Violet (CV) dye removal. h-BN-PVB-H foam composite removes approximately 26% of Reactive Blue 49 (RB 49) dye with an adsorption capacity of 12.313 mg/g in the first 10 minutes. The 3D BN/Polymer foams showed reasonable absorption capacities for olive oil, cyclohexane and toluene from 200-980 wt% relative to the foam’s dry weight. It shows that the produced composite foams can absorb approximately 2-10 times their own weight.

Enhanced mechanical properties of RPET/PA11 blends by chain extender

Recycling is the most effective strategy to lessen the disposal problem. However, recycling will diminish polyethylene terephthalate's mechanical and chemical properties (PET). The molecular weight of PET is diminished due to moisture absorption, biological contaminants, oxidation, high temperature, and thermal degradation. To enhance the properties of recycled PET, it has been blended with Polyamide 11 (PA11) in varying proportions of 30:70, 50:50, and 70:30. Joncryl® chain extender was added to the mixture to improve its properties. Increased PAll content and the incorporation of Joncryl® have increased the flexibility and decreased the brittleness of RPET. Compared to samples, the 30/70 (RPET/PA11) blend ratio with 1% Joncryl® exhibits superior properties. Joncryl® is effective at preventing RPET degradation, hence increasing the Tg of RPET, PA11, and blend. With these enhanced compatibility and mechanical qualities, the compatibilized and non-compatibilized RPET/PA11 blends have the potential to be utilized in applications involving polyester polymers, especially in automotive parts.

Comprehensive study of the radiation shielding feature of polyester polymers impregnated with iron filings

Abstract Radiation and nuclear technologies have side effects in addition to their important applications, so appropriate shields must be used to protect users and the public from high doses as a result of exposure to this radiation. In this work, the attenuation coefficients for polyester composites doped with waste iron filings (IFs) were studied. Six samples of different IF concentrations were manufactured, namely, Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60 (where Poly-IF60 represents 40% polyester and 60% IF). We measured the attenuation factors using high purity germanium (HPGe)-detector along with three radioactive sources 241Am (emitting energy of 0.06 MeV), 137Cs (emitting energy of 0.662 MeV), and Co-60 (emitting energy of 1.173 and 1.333 MeV). We compared the linear attenuation coefficient (LAC) obtained by theoretical (i.e., XCOM software) and experimental (i.e., HPGe-detector) approaches for the prepared polyester composites at various photon energies (0.060, 0.662, 1.173, and 1.333 MeV). The greatest difference between the LAC values of the samples occurs at 0.060 MeV, where the Poly-IF60 sample has a much greater LAC than the other shields, followed by the Poly-IF50 sample, Poly-IF40 sample, and so on until the pure polyester shield. Specifically, their values are equal to 0.245, 0.622, 0.873, 1.187, 1.591, and 2.129 cm−1 for Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60, respectively. We calculated the transmission factor (TF) and the radiation shielding efficiency (RSE), and found that the TF for Poly-IF30 is equal to 28.82%, 77.94%, 82.75%, and 83.75% at 0.060, 0.662, 1.173, and 1.333, respectively, while its RSE is equal to 82.57%, 24.00%, 18.80%, and 17.72%, respectively. The fast neutron removal cross-section (FNRC) of the polyester samples was calculated and the values increase when more Ifs are added to the samples. More specifically, the FNRC values are equal to 0.095, 0.100, 0.103, 0.107, 0.110, and 0.113 cm−1 for Poly, Poly-IF20, Poly-IF30, Poly-IF40, Poly-IF50, and Poly-IF60, respectively.

Effect of silicon dioxide nanoparticle on microstructure, mechanical and barrier properties of biodegradable PBAT/PBS food packaging

Biodegradable polyester polymers including poly(butylene adipate-co-terephthalate) (PBAT) and poly(butylene succinate) (PBS) are used as sustainable and eco-friendly food packaging but poor water vapor barrier properties limit their applications with moisture-sensitive products. This research blended PBAT/PBS materials at 60/40 and 50/50 with silicon dioxide (SiO2) nanoparticles as master batch pellets via twin-screw extrusion before sheet-casting to improve food packaging barrier properties. PBAT/PBS/SiO2 nanocomposite films were investigated by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy and also for mechanical relaxation, microstructure, surface topography, and barrier properties. Scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) indicated dispersed SiO2 nanoparticle aggregation in polymer matrices at higher loading. FTIR spectroscopy results suggested modified CO stretching vibrations in polyesters, concurrent with shifting X-ray diffraction angles depending on nanoparticle content and polymer blend ratios. Adding SiO2 nanoparticles at up to 1% exponentially reduced water vapor permeability by up to 26%, while decreasing oxygen permeability (up to 8%). Mechanical properties reduced when adding SiO2 nanoparticles but film stretching improved polymer orientation at higher loading, thereby increasing tensile strength and elongation. Compounding SiO2 nanoparticles with PBAT/PBS polyester polymer blends enhanced barrier properties for biodegradable food packaging.

Experimental and statistical investigation of flexural and compressive strengths of UPPC: Comparison between moulded and in-situ specimens

This study carries out experimental and statistical investigations on Unsaturated Polyester Polymer Concrete comparing in-situ (cut/cored) and moulded (cast) specimens for flexural and compressive strengths. The comparison is between standard-based cast specimens with those of the cored and cut from constructed elements. The specimens were made to consider different specimen shapes, sizes, and mix-designs, and grouped into three batches for each strength type. The total number of specimens were 75 and 79 for moulded and in-situ, respectively. Their strengths were represented by their statistical partial descriptors and nominal values, where the nominal values were calculated based on the characteristic values and the randomly selected 6 samples (specimens) for comparison. For flexural strengths, cut specimens showed greater averages and variations than cast specimens, although the trend was similar over different batches. For compressive strengths, cast specimens showed greater averages than cored specimens, but the variations were greater in cored specimens. For all cases, the number of specimens considered in this study did not cause noticeable statistical uncertainty, and 6-sample based nominal values could provide unconservative estimates.

Biodegradable Polylactic Acid and Its Composites: Characteristics, Processing, and Sustainable Applications in Sports.

Polylactic acid (PLA) is a biodegradable polyester polymer that is produced from renewable resources, such as corn or other carbohydrate sources. However, its poor toughness limits its commercialization. PLA composites can meet the growing performance needs of various fields, but limited research has focused on their sustainable applications in sports. This paper reviews the latest research on PLA and its composites by describing the characteristics, production, degradation process, and the latest modification methods of PLA. Then, it discusses the inherent advantages of PLA composites and expounds on different biodegradable materials and their relationship with the properties of PLA composites. Finally, the importance and application prospects of PLA composites in the field of sports are emphasized. Although PLA composites mixed with natural biomass materials have not been mass produced, they are expected to be sustainable materials used in various industries because of their simple process, nontoxicity, biodegradability, and low cost.

Comparative analysis of tensile properties on thermoplastic & thermosetting polymer composites

Polypropylene and polyester polymer were used to create the specimens, which were then reinforced with glass fibres. Both the polyester and the polypropylene polymer's composition impacts and tensile qualities were compared and evaluated. In this research, the comparison of thermoplastic and thermosetting plastic material specimens from the above-mentioned proposal and show how they differ from polypropylene in their use of hand wet layup techniques of polyester resin with glass fibre. One synthetic fibre that offers excellent thermal, electrical, and corrosion resistance is made of glass fibres. One thermosetting substance that has great bonding properties is polyester resin. One of the thermoplastic materials that is often durable, reusable, and flexible is polypropylene. This study's findings demonstrate that thermosetting plastic materials have superior tensile characteristics than thermoplastic plastic polymers.