Polypropylene Research Articles

Mechanical, Thermal, and Morphological Analysis of Himalayan Agave Fiber /GO Coated Fly Ash Hybrid Polypropylene Composites.

Composites containing two different types of reinforcements offer a wide range of possibilities and synergistic properties. This study investigates the hybridization effect of chemically active fly ash (FA) (5 wt.%) on the composites made from alkali (1 wt.%) - APTES silane (2 wt.%) treated Himalayan agave fibers (HAF) (25 wt.%) and polypropylene (PP). Prior to FA activation, the planetary ball mill was used to suitably reduce the particle size of the FA with was confirmed by the dynamic light scattering approach. Secondary reinforcement FA was modified with APTES silane (1 wt.%), followed by treatment with graphene oxide (GO) (0.5, 0.75, and 1 wt.%). The highest tensile strength of 40.47 MPa and modulus of 1.49 GPa were observed for the hybrid composites fabricated from 0.75 and 1.0 wt.% GO treated fly ash. Interestingly, this trend differed for flexural properties, and the highest flexural strength of 53.52 MPa was demonstrated by 0.5 wt.% GO treated FA hybrid composite. Thermal characterization revealed that addition of fiber increased crystallinity but decreased thermal stability, whereas a good wettability of the fiber and FA in matrix was demonstrated through morphological characterization.

A systematic review on sustainable utilization of plastic waste in asphalt: assessing environmental and health impact, performance, and economic viability.

Increasing amount of plastic waste (PW) poses a global challenge that necessitates multifaceted strategies. Repurposing PW in asphalt pavement is a sustainable strategy with extensive benefits, but there are several challenges that need to be overcome. This systematic review aims to examine three significant aspects associated with plastic-modified asphalt: environmental and health considerations, performance and technical properties, and cost.-effectiveness and economic feasibility. The environmental and health impacts of using PW in asphalt were particularly focused on the release of carcinogenic compounds and harmful fumes like polyaromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs), microplastic pollution, and climate impact. Environmental challenges and potential health risks associated with the use of PW in asphalt production were analyzed and indicated. Afterwards, the effects of different plastic types on the fatigue and rutting resistance of asphalt pavement are investigated. While many types of PWs show potential for enhancing rutting and fatigue performance, conflicting results have been observed for certain plastics. Some PW types, such as polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS), low-density polyethylene (LDPE), and high-density polyethylene (HDPE), have been shown to yield inconsistent results. Lastly, factors that are recognized to have an impact on the cost-effectiveness of plastic-modified asphalt include the collection and processing costs, asphalt materials price and availability, incorporation method, and possible changes in the asphalt's lifespan. The findings of this review help researchers to identify current gaps and aid stakeholders in making informed decisions towards more environmentally friendly, high-performance, and economically viable approaches to asphalt production.

Modification of polyolefins utilizing C–H insertion of azides: Azidoformate end-functionalized polystyrene for modifying polypropylene

Polyolefins dominate the global plastics industry, constituting roughly 60% of all commercial plastics. However, their limited chemical functionality restricts their applicability in adhesion, printability, and compatibility-dependent applications. To overcome these limitations, this study investigated metal-free, melt-process post-polymerization modification of polypropylene (PP) via C-H insertion of azidoformate (AF) groups. We investigated grafting of AF end-functionalized polystyrene (PS) onto PP and demonstrated the successful preparation of novel PP hybrids with interesting properties, including enhanced compatibility between PP and PS components due to grafting, smaller PP crystallite size, high Young's modulus, and elastic rheological behaviors likely attributable to the presence of PS branches. Importantly, the presented approach avoids chain scission of PP and undesirable coloration of the product, offering a promising avenue for industrial transformations of conventional polyolefins. This research paves the way for developing polyolefin-based hybrid materials with enhanced properties and environmental benefits.

Durability and hardened characteristics of cement mortar incorporating waste plastic and Polypropylene exposed to MgSO4 attack

Annual waste plastic disposal has grown, harming nature. Utilising this waste in concrete production may help preserve building resources. This study tested cement mortar with polyvinyl chloride (PVC) and polypropylene (PP) substituted for sand aggregate at 0, 5, 10, 15, and 20%. The samples were nevertheless exposed to a 10% and 20% MgSO4 solution for a month. The properties of both fresh and hardened materials under these circumstances have been evaluated and contrasted with those evaluated under typical circumstances. For mixes including PP and PVC, the flow diameter increased. The rounded plastic particles provided fewer contact surfaces and less friction among mixtures, which reduced water consumption and improved workability, leading to an increase in slump flow. As the amount of plastic aggregate increases, the compressive strength decreased. Moreover, this pattern might be explained by the weakening of the bond between the surfaces of the plastic aggregate and cement paste. The hydration of cement may also be hampered by the hydrophobic properties of plastic aggregate. Like compressive strength, the splitting tensile strength decreased as the replacement level of plastic ratio increased regardless of its type under all conditions (normal and exposing to MgSO4). PP and PVC fine aggregate in mortar increases sorptivity under all situations. Following screening, those circumstances and PVC have the most impact on compressive strength. increasing PVC and PP at 10% for each of them leads to lower values of compressive and tensile strength. An optimization process was implemented to determine the optimum value of PVC, PP, and MgSO4. It shows that using PVC of 3.9%, PP of 10.1%, and MgSO4 of 19.59% leads to maximum compressive and tensile strength with the minimum cost and CO2 emissions.

Fabrication of high performance polypropylene based blends from ethylene vinyl acetate-based sole waste via solid-state shear Co-milling

Ethylene vinyl acetate copolymer (EVA) foam products with cross-linked structure are now widely used in the fields of functional footwear. However, due to their cross-linked structure and complex composition, they are quite difficult to be recovered in large scale after disposal, causing serious environmental pollution. Based on our self-designed solid-state shear milling (S3M) equipment, a novel co-milling technology was established to recycle ethylene vinyl acetate-based sole waste (ESW) and reuse it to strengthen and toughen polypropylene (PP). The effects of co-milling on PP/ESW powders as well as blends were studied, and the results showed that the existence of PP promoted the solid pulverization of ESW, so formed the powders with smaller size and wider distribution. Ascribing to the partial de-crosslinking of ESW during co-milling process, the contact area and the molecular entanglements at their interfaces increased, effectively improving the compatibility between PP and ESW. In this way, the simultaneous enhancement and toughening of ESW on PP were achieved. After co-milling, ESW phase in blends significantly decreased and no visible phase interface was observed. With 20 co-milling cycles, the tensile strength and impact toughness of PP/20 wt% ESW blend respectively increased from 21.9 MPa to 3.79 kJ/m2 to 25.4 MPa and 5.83 kJ/m2, both higher than most other similar PP based materials. This work provides a new strategy for high-quality and efficient recycling of ESW in large scale, and fabrication of high-performance PP based materials.

Ecofriendly hybrid natural fiber reinforced polypropylene composites from biowastes

The used ground coffee waste (GCW) and tea leaf waste (TLW), the large wastes from the beverage process, were selected as natural reinforcement and natural pigment in the polypropylene (PP) matrix. In this work, the maleic anhydride polypropylene (MAPP) was added to the composites to develop the compatibility between fillers, fibers, and polymer matrix. The TLW/PP composites, GCW/PP composites, and GCW/TLW/PP hybrid composites were prepared in the ratio of TLW and GCW ranging from 0 to 30 wt% with the addition of MAPP at 5 wt% of fillers. The presence of GCW and TLW in the PP matrix decreased tensile properties and impact resistance but increased flexural modulus and hardness of PP at high concentrations of GCW and TLW. The increase in GCW and TLW concentration slightly reduced melting temperature but it enhanced the tensile and flexural modulus. Furthermore, it enhanced the hardness, thermal and rheological properties of the composites. The TLW/PP composites had better mechanical properties, and rheological properties than GCW/PP composites but thermal properties were quite similar. The mechanical properties of GCW/TLW/PP hybrid composites were better than those of GCW/PP composites but lower than those of TLW/PP composites. The rheological and thermal behaviour of hybrid composites were like that of TLW/PP composites. Incorporating MAPP improves the mechanical and rheological behavior of PP composites by enhancing the interaction among PP, GCW, and TLW. However, this addition does not significantly enhance the composites’ thermal properties. The optimum composite was hybrid composites of GCW/TLW/PP consisting of GCW of 10 wt%, TLW of 20 wt%, and MAPP of 1.5 wt% which presented good mechanical, thermal, and rheological properties. The mechanical properties of this hybrid composites were as follows: a tensile strength of 26.35 MPa, elongation at break of 10.91%, tensile modulus of 636.69 MPa, flexural strength of 45.57 MPa, flexural modulus of 3632.86 MPa, impact resistance of 12.72 kJ/m2, and a Shore D hardness of 76.15. The overall results showed that GCW and TLW can be used as reinforcement material and natural pigment in the polymer matrix.

Gamma radiation induced optimized synthesis of amine functionalised poly-glycidyl methacrylate grafted poly-propylene non-woven fabric and its adsorption behaviour towards aqueous Pb(II)

Comprehensive optimization of the functionalization of polypropylene (PP) non-woven fabric through gamma irradiation-induced graft polymerization of glycidyl methacrylate (GMA), results in a material having high grafting yield. The technique, utilizing a mutual irradiation method, produced poly-GMA (PGMA) grafted PP fabric with a remarkable grafting yield of 125 % in a 1:1 acetone–water mixture, subjected to 25 kGy of total dose at a dose rate of 5 kGyh−1. The enhancement of the amination process utilizing PGMA-grafted PP was investigated with polyamines. Under the optimized conditions, the diethylene triamine (DETA) functionalized variant was identified as an effective adsorbent for aqueous Pb2+ ions. The optimized adsorbent exhibited a high saturation capacity of approximately 230 mgg−1 for Pb2+ ions, demonstrating rapid kinetics at near-neutral pH and 25 °C. This low cost innovative material holds significant promise for effective lead removal from drinking water and industrial wastewater, offering a sustainable economical solution for environmental remediation.

Advanced Machine Learning and Experimental Studies of Polypropylene Based Polyesters Tribological Composite Systems for Sustainable Recycling Automation and Digitalization

Digitalization and automation are emerging solutions to the complex problems of recycling. In this research work, the experimental and Python based Archard deep learning wear rate models are introduced regarding recycling automation and composite tribological systems optimization. The optimum polyester fibers (PESF) of length of 3-3.5 mm were used for fabrication of polypropylene (PP)-PESF composite systems. The deformation, high texture, asperities, and micro-cracks were observed during scanning electron microscope and machine-learning studies. The lowest experimental value of abrasive wear of 3.0 × 10-6 mm3/Nm was observed for PP. Comparatively, higher experimental values of abrasive wear of the PP-PESF composites are found in the range of 4.35 × 10-6 to 4.7 × 10-6 mm3/Nm due to presence micro-defects on the surface of composites. The experimental values of Coefficient of friction (COF) of PP and PP-PESF are found in the range of 0.70 - 0.8 and 1.1 - 1.3, respectively. The experimental values of abrasive wear and COF are found compatible with literature. Similarly, the simulated values of abrasive wear of PP and PP-PESF composites are predicted in the range of 4.8×10-7 to 3.75×10-7 mm3/Nm, respectively. The predicted values of PP and PP-PESF composite show better resistance towards abrasive wear. The proposed experimental and simulated (in terms of Python coding, machine learning, image processing, artificial intelligence, and deep learning studies) research work can be introduced industrially for automation as well as digitalization of grinding of PES waste, processing, tribological testing, and SEM characterization evaluations.

Impact of Jellyroll Tapes on Performance of Layered Oxide/Hard Carbon Sodium-Ion Pouch Cells

This study investigates the influence of jellyroll tape materials on the cycle life and self-discharge of layered oxide/hard carbon sodium-ion pouch cells. Jellyroll tapes made of polyethylene terephthalate (PET) or polypropylene (PP) polymer were used in this study. Severe PET tape decomposition was observed in additive-free electrolyte. The use of solid-electrode interphase forming additives suppressed PET tape decomposition effectively and resulted in a competitive performance comparable to that of cells with PP tape. Replacing PET tape with PP tape led to sodium-ion pouch cells with substantial improvements of capacity retention, coulombic efficiency, and charge endpoint slippage. The superior chemical stability of PP tape in sodium-ion batteries allows for long cycle life and low self-discharge even in the absence of additives.

The addition of humic acid into soil contaminated with microplastics enhanced the growth of black gram (Vigna mungo L. Hepper) and modified the rhizosphere microbial community.

Microplastics have polluted agricultural soils, posing a substantial risk to crop productivity. Moreover, the presence of microplastic pollution has caused a disturbance in the composition of the microbial community in the soil surrounding plant roots, therefore impacting the growth of beneficial bacteria. A study was conducted to examine if humic acid (HA) can counteract the harmful effects of microplastics (MPs) on the growth of black gram crops and the composition of the rhizosphere soil microbial community, to reduce the negative impacts of microplastics on these microorganisms and crops. The research was carried out using mud pots and the plastic utilized for the experiment consisted of 60% high-density polyethylene (HDPE) and 40% polypropylene (PP). The soil was enriched with lignite-based potassium humate, which had a pH range of 8.0-9.5 and with 65% humic acid. The experiment consisted of six treatments: T1, which served as the control without HA and MP; T2, which involved the use of HA at a concentration of 0.15% w/w; T3, which involved the use of MP at a concentration of 0.2% w/w; T4, which involved the use of MP at a concentration of 0.4% w/w; T5, which involved the combination of HA at a concentration of 0.15% w/w and MP at a concentration of 0.2% w/w; and T6, which involved the combination of HA at a concentration of 0.15% w/w and MP at a concentration of 0.4% w/w. The plant growth characteristics, including germination percentage, nodule number, and chlorophyll content, were measured. In addition, the DNA obtained from the rhizosphere soil was analyzed using metagenomics techniques to investigate the organization of the microbial population. Seedlings in soil polluted with MP exhibited delayed germination compared to seedlings in uncontaminated soil. Following 60days of growth, the soil samples treated with T5 (0.2% MP and 0.15% HA w/w) had the highest population of bacteria and rhizobium, with counts 5.58 ± 0.02 and 4.90 ± 0.02CFUg-1 soil. The plants cultivated in T5 had the most elevated chlorophyll-a concentration (1.340 ± 0.06mgg-1), and chlorophyll-b concentration (0.62 ± 0.02mgg-1) while those cultivated in T3 displayed the lowest concentration of chlorophyll-a (0.59 ± 0.02mgg-1) and chlorophyll-b (0.21 ± 0.04mgg-1). Within the phylum, Proteobacteria had the highest prevalence in all treatments. However, when the soil was polluted with MPs, its relative abundance was reduced by 8.4% compared to the control treatment (T1). Conversely, treatment T5 had a 3.76% rise in relative abundance when compared to treatment T3. The predominant taxa found in soil polluted with MP were Sphingomonas and Bacillus, accounting for 19.3% of the total. Sphingomonas was the predominant genus (21.2%) in soil polluted with MP and supplemented with humic acid. Humic acid can be used as a soil amendment to mitigate the negative effects of MPs and enhance their positive advantages. Research has demonstrated that incorporating humic acid into soil is a viable method for maintaining the long-term integrity of soil's physical, chemical, and biological characteristics.

Deciphering the role of nonylphenol adsorption in soil by microplastics with different polarities and ageing processes.

In the soil environment, microplastics (MPs) commonly coexist with organic pollutants such as nonylphenol (NP), affecting the migration of NP through adsorption/desorption. However, few studies have focused on the interaction between NP and MPs in soil, especially for MPs of different types and ageing characteristics. In this study, non-polar polypropylene (PP) and polar polyamide (PA) MPs were aged either photochemically (144 h) or within soil (60 days), then used to determine the effect of 5 % MPs on the adsorption behaviour of NP (0.1-4.0 mg/L) in soil. Results showed that both ageing processes significantly promoted the conversion of -CH3 groups to C-O and CO on the surface of PPMPs, while PAMPs exhibited amide groups changes and a reduction in average particle size due to ageing. Additionally, both ageing processes promoted the adsorption of NP by soil containing PPMPs, due to an increase in oxygen-containing functional groups and specific surface area. In contrast, the NP adsorption capacity of soil containing PAMPs decreased by 15.4 % following photochemical ageing due to hydrolysis of amide groups, but increased by 21.15 % after soil ageing due to reorganization of amide groups, respectively. The soil-PAMPs systems exhibited a stronger affinity for NP compared to the soil-PPMPs systems, which was primarily attributed to the dominant role of hydrogen bonding. NP was found to be distributed mainly on soil particles in the soil-PPMPs systems, while it tended to be adsorbed by MPs in the soil-PAMPs systems, especially in the soil aged MPs system. This study provides a comprehensive analysis of the complex effects of MPs on coexisting pollutants in soil environments, highlighting the effect of MP characteristics on the adsorption of organic pollutants, which is essential for understanding the transport behaviour of organic pollutants.

Bio-inspired widening concrete using cellulose nanofiber to enhance multiscale Fiber–Matrix interface

The cracking issue at the bonded interface due to the differing shrinkage performances of newly poured concrete and existing concrete poses a significant threat to the safe service of composite structures. Inspired by the musculoskeletal system, we propose the use of multiscale hybrid reinforced concrete materials, incorporating basalt fiber (BF), polypropylene (PP) fiber, and cellulose nanofiber (CNF), for bridge widening structures. Experimental investigations were carried out to assess the bond splitting tensile strength, diagonal shear strength, crack resistance, development of drying shrinkage deformation, and the propagation behavior of restrained shrinkage-induced cracks in both new and old concrete reinforced with single and hybrid combinations of BF, PP fiber, and CNF. The microstructure, phase composition, and pore structure evolution of BF, PP fiber, and CNF-reinforced concrete were observed and analyzed using scanning electron microscopy, thermogravimetric and derivative thermogravimetric analysis, nuclear magnetic resonance, and mercury intrusion porosimetry. The results indicate that the incorporation of BF, PP fiber, and CNF exhibits excellent synergistic effects, improving the bond and shrinkage performance of the concrete interface. As the CNF content increases, the macro fiber–matrix interface improves. This bio-inspired work will contribute to the development of strong, tough, and sustainable concrete for bridge widening structures.

Decreased Sulfamethoxazole Uptake in Lettuce (Lactuca sativa L.) due to Transpiration Inhibition by Polypropylene Microplastics

Microplastics and antibiotics are emerging contaminants in agricultural soil that can have negative effects on crops. However, limited research has been conducted on the effects of the polypropylene (PP) microplastic and sulfamethoxazole (SMX) co-exposure on crops, specifically regarding the impact of PP microplastics on SMX uptake and transport in crops. In this study, hydroponic experiments were carried out using lettuce (Lactuca sativa L.), PP microplastics (1.0 g L-1), and SMX (0.5 mg L-1 or 2.5 mg L-1) to investigate the individual and co-exposure effects of PP microplastics and SMX on Lettuce growth, explore the uptake and translocation of SMX in lettuce and elucidate the underlying mechanism of PP microplastic impact on SMX uptake. Results demonstrated that co-exposure to 1.0 g L-1 of PP microplastics and 0.5 mg L-1 of SMX resulted in an enhanced toxic effect. However, no intensified toxic effect on the lettuce was observed when 1.0 g L-1 PP microplastics were added in the presence of 2.5 mg L-1 SMX, indicating that the SMX dominated the toxic effect on lettuce at high concentrations. Additionally, the study found that the water absorption process controlled by the aquaporin and transpiration contributed to the uptake and translocation of SMX in lettuce. When exposed to PP microplastics, no impact was observed on the aquaporin contents of the lettuce while the transpiration rate was significantly decreased by 31.6 % - 44.2 % resulting from microplastics adhered to the root surface. Therefore, in the presence of 2.5 mg L-1 SMX, the SMX uptake in the lettuce root was inhibited by 35.9 % (P < 0.05) when exposed to 1.0 g L-1 PP microplastic. This work deepens our understanding of the behaviour of microplastics and antibiotics in the terrestrial environment.

Manufacturing and Characterization of Polypropylene-Paper Composites for Automotive Applications

The automotive industry is under significant pressure to curb greenhouse gas emissions from their products as the negative impacts on the environment are increasingly apparent. As such, there is significant interest within the industry to develop low-carbon footprint materials. Natural fiber composites are therefore appealing due to both their decreased carbon footprint, as well as their relatively low cost, low density, and beneficial acoustic properties. This research specifically focuses on the use of paper fibers as composite reinforcements. Paper offers additional benefits over other natural fiber types in that it is globally available, does not compete with food resources, and has well-established quality control techniques. The goal of this work was to study the manufacturing of polypropylene (PP)-paper fiber composites using a hybrid wet-lay/compression molding processing. The processing parameters studied included molding temperature, molding duration, and molding pressure. Paper composites were characterized for properties including flexural strength, impact strength, and water uptake rate. An optimal set of processing parameters was identified in which cycle time and energy inputs (e.g. temperature and pressure) were minimized while retaining desired material properties.

Contact Antibacterial and Biocompatible Polymeric, Composite with Copper Zeolite Filler and Copper Oxide, Nanoparticles: A Step Towards New Raw Materials for the Biomedical Industry

This paper introduces a simple procedure for developing composite materials with antibacterial and biocompatible properties using polylactic acid (PLA) and polypropylene (PP). These composites incorporate three variants of zeolites in different percentages as filler agents: pure zeolite (PZ), copper ion-saturated zeolite (LZ), and copper-ion-saturated zeolite with copper oxide nanoparticles (LZ-nCu). The composites were prepared by the extrusion method and manufactured by injection molding. The impact of these zeolites on various material properties was evaluated, including morphology, thermal stability, mechanical properties, antibacterial capacity, biocompatibility, water absorption, and chemical resistance. The results demonstrated that (i) the incorporation of zeolite into the PP matrix improved thermal stability and increased the tensile modulus of the composites. For PLA-based composites, although there was a slight decrease in these values compared to pure PLA, they remained within acceptable ranges; (ii) zeolite LZ and LZnCu composites at 5 and 10% by weight effectively inhibited the growth of Gram-positive and Gram-negative bacteria within a maximum of 2 hours of contact; and (iii) composites containing 10% by weight of PZ, LZ, or LZ-nCu showed reduced mechanical properties due to a tendency to form agglomerates. Additionally, LZ and LZ-nCu composites with the same percentage proved highly toxic to human gingival fibroblast cells (HGFs). PLA/LZ-nCu at 5% and PP/LZ at 5% composites exhibited antibacterial properties with bactericidal effects upon contact, high biocompatibility, and lower water absorption compared to the pure polymeric matrix. These results highlight the operational effectiveness of the procedure and suggest the potential of these composites in biomedical applications, such as in vitro dentistry, without contamination risks.

Ultra-tough, strong and transparent bio-based waterborne polyurethanes with exceptional anti-corrosion properties

Waterborne polyurethane (WPU) is increasingly favored because of its affordability, eco-friendliness, and water-based storage convenience. However, the inclusion of hydrophilic groups can diminish its mechanical strength and water resistance. Herein, we synthesized a range of bio-based waterborne polyurethanes that exhibit superior mechanical properties, transparency, and corrosion resistance using economical and sustainable bio-based poly(trimethylene ether) glycol (PO3G), isophorone diisocyanate (IPDI), and poly(propylene glycol) (PPG) as raw materials. We explored how varying the PO3G content affects the properties of these bio-based WPU emulsions and films. The findings revealed that films with over 30% PO3G content demonstrated tensile strengths exceeding 10 MPa and maintained a high elongation at break (above 4000%), matching or surpassing existing bio-based WPU systems. The corrosion resistance of these films was also exceptional, with a high inhibition efficiency (above 99.97%). This research introduces a new approach for creating high-performance bio-based WPUs with promising applications in coatings, leather, and biomedical materials.

Co-pyrolyzed biochar derived from microplastics and microalgae as peroxymonosulfate activator: Influence of microplastic types and analysis of systemic causes

This work investigated the catalytic activity of co-pyrolyzed biochar (MP-SBC) from microplastic (MP) and Spirulina biomass and its activation mechanism for peroxymonosulfate (PMS). Given that different types of MPs had varied effects on the properties of biochar, polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), and polylactic acid (PLA) were chosen as MP feedstocks. The results showed that the four kinds of MP-SBCs activated PMS more efficiently than the pristine algal-based biochar (SBC), with 100 % of the acetaminophen (ACT) degraded within 20 min. Based on the reaction mechanism analysis, the main pathways for the degradation of ACT by SBC and MP-SBC activated PMS were both non-radical pathways, and ACT was also efficiently degraded by the synergistic effect of 1O2 and electron transport pathway (ETP). Moreover, it was found that the microplastic modification could significantly enhance the efficacy of SBCs in triggering the non-radical pathway. Establishing the correlation between the structural features of BC and the degradation mechanism (active species contribution) revealed that the persistent free radicals (PFRs), defective structures, CO, and graphite N are all potential active sites. Thereinto, PFRs are the active sites for radicals, defects are the active sites for 1O2 production, and CO, defects, and graphitic N are the active sites for ETP. Overall, this work provides an innovative approach for designing efficient biochar-based catalysts for environmental remediation.

Tailored PEO/PEG-PPG Polymer Electrolyte for Solid-State Lithium-Ion Battery

Abstract Solid polymer electrolytes (SPEs) offer a promising avenue for advancing the performance and safety of all-solid-state batteries. In this study, we investigated the effects of blending poly(ethylene oxide) (PEO) with amorphous poly(propylene glycol) (PPG) or poly(ethylene glycol-ran-propylene glycol) (PEG-PPG) to engineer SPEs with enhanced electrochemical properties. By blending PEO with PEG-PPG or PPG, we effectively lowered the crystallinity of PEO, facilitating the diffusion of lithium ions through the SPE and broadening its operational temperature range. This optimization strategy enhanced ionic conductivity and significantly reduced the interfacial resistance between the electrolyte and electrode, thus improving electrochemical stability. The solid-state lithium/lithium iron phosphate (LiFePO4 or LFP) with PEO blended with 7% PEG-PPG showed excellent charge/discharge cycling stability, with maximal discharge capacities of 165 mAh g-1 and 162 mAh g-1 at a current rate of 0.2 C at 60 and 125°C, respectively. The PEG-PPG-based SPE outperformed the PPG polymer-based SPE in terms of better electrochemical performance and a wider temperature range due to its longer polymer chain. This combination offered improved ionic conductivity, interface stability, and electrolyte compatibility with electrodes, making it highly suitable for high-demand applications of lithium-ion batteries.

Effect of high quality hybrid coatings and coating condition on the properties of continuous glass fiber reinforced polypropylene prepreg composites

AbstractDue to the difficulty in infusing resin into interiors of fiber bundles by prevalent pre‐impregnation methods like melt impregnation and the substantial polarity difference between glass fibers (GF) and polypropylene (PP), the application of continuous glass fiber reinforced polypropylene (CGF/PP) composites has been restricted. In this study, a hybrid emulsion is prepared to address the polarity difference through coating process. And further by optimizing coating process parameters, composites glass fibers with excellent performance can be obtained. The study demonstrates that the composite glass fiber with coating amount of 15.34% exhibits good bunching and flexibility. The monofilament tensile strength and interfacial shear strength (IFSS) are increased by 2.53% and 109.74%, respectively compared to the desized glass fiber (GF0). Furthermore, after the hot‐pressing process, the composites glass fiber bundles show fully filled gaps and a completely wrapped surface. This study lays the foundation for producing CGF/PP prepreg composites conveniently, efficiently, and commercially.

Development of Flexible Hydrophobic Polypropylene/SPCB/GNP Hybrid Nanocomposite Films With Excellent EMI Shielding and Mechanical Properties

ABSTRACTThe demand for effective electromagnetic interference (EMI) shielding materials has driven the development of novel and facile approach for fabrication of conductive polymer nanocomposites. In this study, a polypropylene (PP)‐based hybrid nanocomposite was prepared by incorporating Super P conductive carbon black (SPCB) and graphene nanoplatelets (GNP) via latex technology. A simplistic method of fabrication was adopted where the nanofillers were stirred into the PP latex at room temperature, ensuring the proper dispersion of fillers within the matrix. Hybridizing the nanocomposite by the usage of two different fillers has resulted in a substantial improvement in EMI shielding performance of the material along with its mechanical and thermal properties. The samples were fabricated and tested in three different thicknesses to ensure that EMI shielding effectiveness (EMI SE) is a thickness dependent property and also the studies were carried out over a broad range of microwave frequency. A high electrical conductivity of 7.6 S m−1 was obtained and exceptional EMI SE of 65 dB (X band), 69.76 dB (Ku band), and 72.38 dB (K band) was showcased by 2 mm thickness composites. The optical images of PP latex incorporated with the fillers gave a clear understanding about the formation of conducting networks within the polymer matrix at percolation threshold. The addition of SPCB and GNP also showed a significant increase in hardness and tensile strength of the composite and helped in protecting the polymer matrix against photo radiation. The fillers also aided in the enhancement of the hydrophobicity of the films. The thermal stability, crystallization temperature (TC) and melting temperature (TM) of the composites were also improved when compared to that of neat The works aims at fabricating a hydrophobic and low‐density polymer nanocomposite showing excellent absorption dominant EMI SE.