Polypropylene Materials Research Articles

A zinc-embedded multicomponent copolymer customized for polypropylene and its synergistic flame-retardant effect and outstanding mechanical properties

The poor compatibility between the common polar intumescent flame-retardant system (IFR) and the nonpolar polypropylene (PP), as well as the high additive amount, seriously impacts the mechanical properties of the composites. This study introduced collaborative flame-retardant technology to construct block copolymer flame retardants and prepared a zinc-embedded multicomponent copolymer (PM-Zn2+) customized for PP composites. In the PM-Zn2+ system, zinc oxide was embedded into the copolymer composed of piperazine phosphate oligomer and melamine phosphate. PM-Zn2+ exhibited an amorphous structure with extremely low crystallinity and demonstrated specific morphological adaptability. The PM-Zn2+ were well dispersed in the PP matrix and changed their morphology during processing. When applied to PP, excellent flame retardancy and mechanical properties were obtained by using a minimal amount of flame retardants (20 %). PM-2 %Zn2+ gave PP an LOI value of 31.5 %, and achieved a UL94 V-0 rating (1.6 mm thick), exhibiting a lower heat release rate and smoke release. The flame-retardant mechanisms of PM-Zn2+ mainly involved the synergistic and aggregative effects. Transition metal zinc synergistically interacted with polyphosphate groups to create a charring barrier effect and enhance synergistic smoke suppression, leading to a significant reduction in combustion intensity. In comparison to the Mix-Zn/PP composites, the mechanical properties of PM-Zn2+/PP were significantly enhanced due to the specific morphological adaptability and improved compatibility. The elongation at break increased significantly from 15.6 % to 627.9 %, marking a remarkable improvement of 40-fold improvement, while the impact strength rose from 23.7 kJ/m2 to 54.3 kJ/m2, representing a 129 % enhancement. Finally, the zinc-embedded multicomponent block copolymer offers a promising approach to developing high-performance flame-retardant polypropylene materials.

Subtle differences in recycled polypropylene from rheology to additives impacts ease of circularity in materials extrusion additive manufacture

The decentralized production associated with material extrusion additive manufacture (MEX) has been proposed as an ideal path to increase the circularity of plastics through direct recycling. Although multiple studies have reported on the 3D printing of various recycled plastics, variability in recycled materials, in particular post-consumer waste, challenges the direct extension of these results into production through MEX. Here, we demonstrate filament fabrication and printing of post-consumer polypropylene (PP), where the PP is sourced from clear, cold drink cups from three large international food service and beverage retail chains to provide well defined plastic waste that is perfectly sorted for recycling. These sources for the recycled PP were selected due to their ready availability to enable the results to be directly applied for hobbyist printing, blow molded products to provide good mechanical performance, and the clarity of the PP that suggests formulation design to minimize the PP crystal size. Despite the similarities in the end use product and their physical appearance, the source for the PP impacted the mechanical properties and the visual appearance of the printed objects. These differences can be directly traced to the rheological properties and oxidative stability of the PP at conditions relevant with the print process. These results clearly illustrate differences in initial formulation design and branding details, even when the product is for the same application, impacts the performance of recycled plastics in AM. The high viscosity associated with the PP from blow molding leads to requirements for higher extrusion temperatures for printing. The combination of high temperature and shear during extrusion process of 3D printing degrades the recycled PP. For circularity with MEX with recycled PP, one needs to consider the evolution in the properties of the polymer. Rheological details of recycled plastics are critical to selection of processing conditions and performance of MEX parts. Reporting of rheological data of recycled plastics and these properties after printing is critical to enable translation towards circular 3D printing of recycled plastics.

Experimental Investigation on Mechanical properties of CF15PET and GF30PP materials produced with different raster angles

Abstract In recent years, additive manufacturing (AM) technologies have been used in many industries, such as automotive, defense, space, and aviation. Depending on the development of this technology, the effect of the relationship between many parameters, such as raster angles, production speed, and melting temperature used during the production of materials, has been an important issue in the mechanical properties of materials. In this study, the effects of ±45° and 0–90° raster angles used during the production of 15 % short carbon fiber reinforced polyethylenetereflatate (CF15PET) and 30 % short glass fiber reinforced polypropylene (GF30PP) materials on the mechanical properties of the materials were investigated. As a result of the study, it was determined that different raster angles affect the mechanical properties of both materials.

Do weathered microplastics impact the planktonic community? A mesocosm approach in the Baltic Sea

Microplastics (MPs) are ubiquitous pollutants of increasing concern in aquatic systems. However, little is still known about the impacts of weathered MPs on plankton at the community level after long-term exposure. In this study, we investigated the effects of weathered MPs on the structure and dynamics of a Baltic Sea planktonic community during ca. 5 weeks of exposure using a mesocosm approach (2 m3) mimicking natural conditions. MPs were obtained from micronized commercial materials of polyvinyl chloride, polypropylene, polystyrene, and polyamide (nylon) previously weathered by thermal ageing and sunlight exposure. The planktonic community was exposed to 2 μg L-1 and 2 mg L-1 of MPs corresponding to measured particle concentrations (10–120 μm) of 680 MPs L-1 and 680 MPs mL-1, respectively. The abundance and composition of all size classes and groups of plankton and chlorophyll concentrations were periodically analyzed throughout the experiment. The population dynamics of the studied groups showed some variations between treatments, with negative and positive effects of MPs exhibited depending on the group and exposure time. The abundance of heterotrophic bacteria, pico- and nanophytoplankton, cryptophytes, and ciliates was lower in the treatment with the higher MP concentration than in the control at the last weeks of the exposure. The chlorophyll concentration and the abundances of heterotrophic nanoflagellates, Astromoeba, dinoflagellate, diatom, and metazooplankton were not negatively affected by the exposure to MPs and, in some cases, some groups showed even higher abundances in the MP treatments. Despite these tendencies, statistical analyses indicate that in most cases there were no statistically significant differences between treatments over the exposure period, even at very high exposure concentrations. Our results show that weathered MPs of the studied conventional plastic materials have minimal or negligible impact on planktonic communities after long-term exposure to environmentally relevant concentrations.

Assessment of TiO2 (nano)particles migration from food packaging materials to food simulants by single particle ICP-MS/MS using a high efficiency sample introduction system

TiO2 is the most widely used white pigment in plastics and food packaging industry, thus the question of its migration towards food and hence the impact on consumers is raised. Since recent research indicate its potential toxicity, it is necessary to study TiO2 contamination as a consequence of food storage. For this purpose, plastic containers from commercially-available dairy products and custom-made TiO2-spiked polypropylene materials were put in contact with 50% (v/v) ethanol and 3% (w/v) acetic acid, which were used here as food simulants. The migration assays were carried out under standard contact conditions of packaging use (as recommended by Commission Regulation (EU) N° 10/2011 for food contact migration testing), and under conditions of extreme mechanical degradation of the packaging. The TiO2 (nano)particles released in the food simulants were analysed by single particle inductively coupled plasma-tandem mass spectrometry in mass-shift mode and using a high efficiency sample introduction system (APEX™ Ω) to avoid matrix effects from food simulants. For the dairy product containers and for the spiked polypropylene, results showed release of TiO2 particles of rather large sizes (average size: 164 and 175 nm, respectively) under mechanical degradation conditions, i.e. when the polymeric structure is damaged. The highest amounts of TiO2 were observed in 50% ethanol after 10 days of storage at 50 °C (0.62 ng cm−2) for the dairy product containers and after 1 day of storage at 50 °C (0.68 ng cm−2) for the spiked polypropylene. However, the level of Ti released in particle form was very small compared to the total Ti content in the packaging and far below the acceptable migration limits set by European legislation. Release under standard contact conditions of use of the container was not measurable, thus the migration of TiO2 particles from this packaging to dairy products among storage is expected to be negligible.

Fabrication of pore-filling cation-exchange membrane from waste polystyrene and Spunbond Meltblown Spunbond (SMS) non-woven polypropylene fabric as the substrate

Commercial ion-exchange membranes are typically thick, possessing limited mechanical strength, and have relatively high fabrication costs. In this study, we utilize a three-layer polypropylene fabric known as Spunbond Meltblown Spunbond (SMS) as the substrate. This choice ensures that the resulting membrane exhibits high strength and low thickness. SMS substrates with various area densities, including 14.5, 15, 17, 20, 25, and 30 g/m2, were coated with different concentrations of waste polystyrene solution (ranging from 5 × 104 to 9 × 104 mg/l) before undergoing sulfonation using concentrated sulfuric acid. The physicochemical and mechanical properties of the membrane were characterized and compared with those of commercial Neosepta CMX and Nafion-117 cation-exchange membranes. Remarkably, the fabricated membrane exhibited good performance compared to commercial ones. The cation-exchange capacity (2.76 meq/g) and tensile strength (37.15 MPa) were higher, and the electrical resistance (3.603Ω) and the thickness (130 μm) were lower than the commercial membranes.

Engineered thin coatings of cross-linked silane polymers with urea group onto polypropylene fabrics for controlled release of thymol against molds in hay

With world population on the rise, animal food source production has significantly increased. Susceptibility of hay and other sources to molds poses a serious threat to food quality and safety. This study proposes an innovative approach to address this issue – an anti-mold fungicide comprising thymol bound on silica urea thin coating of polypropylene fabrics. The coating enhances the thermal stability of thymol allowing prolonged release. Coating composition and morphology as well as thermal stability and release rates were investigated. The coating provided efficient protection against mold growth with no side effects on hay exposed to thymol fumes. The results underscore the potential of this fungicide as a safe and effective hay preservative.

The sound absorption properties of a double-leaf micro perforated panel (DL-MPP) made from a double-layered polypropylene material.

Micro-perforated panel sound absorbers are recognized as an alternative method for noise control, offering advantages over conventional porous absorbers. However, the sound absorption of a single micro-perforated panel (MPP) is limited in its ability to cover a broad range of frequencies, especially in the low-frequency region. Therefore, the primary focus of this study is to investigate the sound absorption performance of a double-leaf micro-perforated panel (DL-MPP) absorber, which aims to achieve high sound absorption across a wide frequency range. This study examines the impact of varying parameters, including perforation ratio, diameter of perforated holes, and air gap thickness, on the sound absorption characteristics of a polypropylene-based DL-MPP absorber. Polypropylene was used as the sound absorption material for this investigation. The DL-MPP absorber consists of two perforated panels installed parallel to a rigid back wall, with an air gap between them. To assess the sound absorption performance, a prototype of the DL-MPP absorber was fabricated and tested using a two-microphone impedance tube method following ASTM E1050 standard. The results demonstrate that the optimal sound absorption performance was achieved by designing the MPPs with a 1% perforation ratio, 1 mm diameter of perforated holes, and a 1 mm sample thickness.

Hydrophilic surface modification of polypropylene by AC-DBD and NS-DBD

Dielectric barrier discharge (DBD) is a method to modify material surfaces by creating low-temperature plasma at atmospheric pressure. However, in comparison to low-pressure discharge, atmospheric DBD has the drawback of uneven surface treatment due to the ease of forming filamentary channels. This limitation hinders the widespread application of DBD technology in material surface modification. In this study, the surface of polypropylene (PP) was treated using high frequency alternating current (AC) and nanosecond (NS) pulsed argon DBDs to improve surface hydrophilicity. The changes of the PP surface hydrophilicity and the treatment uniformity were characterized by water contact angle (WCA) measurement. The relationships between the DBD characteristics, the treatment effect and the treatment uniformity of the PP surface were investigated using electrical and optical diagnostic techniques. The PP material surfaces before and after plasma treatments were evaluated by the physical morphology and chemical composition measurements to examine the influence of DBD on the treatment effect and uniformity on the PP material surface. The findings show that the modification by AC-DBD reduces the WCA of PP material surface by 40°∼50° and exhibits a variance of 1.77, indicating an improvement in hydrophilicity to some extent. Furthermore, the modification by NS-DBD further decreases the WCA of PP material surface, reducing the variance to 1.14. Compared with AC-DBD, NS-DBD has a better uniformity, a higher concentration of active particles in plasma, a greater surface roughness of PP material after treatment, a better hydrophilicity and a more uniform effect with less energy consumption. The results are meaningful to improve the application of DBD in material surface modification and optimize the power source election and operation parameters.

Preparation and characterization of multipurpose polypropylene composite with outstanding flame retardancy and antistatic property

AbstractTo enhance the safety grade and broaden the application scope of polypropylene in coal mines, the calcium alginate@ammonium polyphosphate@graphite microsheet (CA@APP@GM) had been synthesized and introduced into the polypropylene (PP) material to endow excellent flame retardancy, antistatic characteristics, thermostability, combustion behavior, and mechanical performance. Physical characterizations on the chemical composition and microstructure of both the gaseous and condensed phase products indicated that the phosphorus‐containing compounds were found in the char residue which were beneficial to accelerate the charring reaction to terminate the mass and heat transfer process. Hence, the CA@APP@GM executed the condensed‐phase flame‐retardant mechanism to enhance the fire resistance of PP matrix. Consequently, it is believed that the CA@APP@GM, with its remarkable flame retardancy and antistatic properties, has the potential to significantly expand the range of applications for PP materials in coal mines.

Investigating Load Calculation for Broken Ice and Cylindrical Structures Using the Discrete Element Method

Ice loads are critical forces that impact the structural integrity of offshore equipment in high-latitude sea areas and play a pivotal role in the design of structures in ice-prone regions. The primary objective of this study is to investigate both experimental and numerical approaches to analyze ice loads on marine structures, elucidate their characteristics and patterns, and offer technical support for the design of structures in ice-prone areas. To achieve this goal, an ice model was built using polypropylene material, and experiments were conducted in a wave flume at room temperature to measure the ice resistance on cylindrical structures. Structural loads were assessed at various ice velocities while maintaining a fixed ice concentration. Furthermore, a high-performance discrete element technology was employed to develop a numerical simulation method for calculating ice resistance on cylindrical structures. Sensitivity analysis was conducted to evaluate the influence of discrete element density on the resistance outcomes. The predicted structural resistance for ice velocities corresponding to the experimental conditions was compared with the results obtained from the model experiment. The research findings indicate that the primary cause of ice resistance is the interaction between the structure and fragmented ice, which leads to collisions, friction, rotation, and local ice accumulation. To quantify the resistance, ice resistance coefficients were defined using an average resistance formula, representing different statistical values. These coefficients were found to remain relatively constant at varying sailing speeds. The results obtained through the discrete element method for ice resistance demonstrated a remarkable agreement with the experimental findings, both in terms of observed phenomena and numerical values. This agreement serves as evidence substantiating the effectiveness of the numerical approach. These methods offer efficient and accurate load prediction solutions for the design of structures in cold regions.

Plasma-induced Polymerization and Grafting of Acrylic Acid on the Polypropylene Nonwoven Fabric Using Pulsed Underwater Diaphragm Electrical Discharge

Polypropylene (PP) nonwovens are used in many hygiene, healthcare and medical products due to their low cost, high chemical resistance and inertness. From an economic point of view, PP textiles would be used as an excellent support material in regenerative medicine or tissue engineering, but here surface functionalization is necessary to ensure cell adhesion and proliferation. Acrylic acid (AAc) is an excellent source of carboxylic-rich (-COOH) coatings suitable for this purpose, but their multistep preparation is time-consuming. Plasma polymerization provides an excellent solution to this demanding procedure since the process of polymerization and grafting to the substrate takes place simultaneously. Here, we propose a relatively fast and effective method for AAc plasma polymerization by using a pulsed underwater diaphragm electrical discharge operated in an aqueous solution consisting of AAc. AAc layers are successfully grafted onto PP nonwovens, which are continuously rewound through the slit where the plasma is generated. The presence of plasma polymerized AAc layer in the fibrous structure of PP nonwoven was monitored by SEM, FTIR and XPS measurements. Additionally, the improved wettability and adhesion characteristics were investigated by the critical wetting surface tension (CWST) method, the standard method of strike-through time (STT) and „tape-peel“ test. Resulting AAc modified PP nonwoven possesses hydrophilic character, enhanced adhesion and a considerable amount of -COOH groups on the surface. Although after the washing test the FTIR and XPS results indicated a lower concentration of the carboxylic groups, the CWST and STT measurements confirmed the stable hydrophilic character of the PP nonwovens surface.

Α coherent optimization course of the silicon nitride nanofiller load in medical grade isotactic polypropylene for material extrusion additive manufacturing: Rheology, engineering response, and cost-effectiveness

By enabling the development of complex structures with adaptable qualities, techniques for additive manufacturing have opened new routes for material development and research. In this research, silicon nitride (Si3N4) ceramic nanoparticles are incorporated into polypropylene (PP) matrices. Various loading levels and standardized test specimens that adhere to ASTM criteria are created. The main goal is to thoroughly characterize these composites with an emphasis on their mechanical capabilities. The rheological, thermomechanical, and morphological properties of 3D-printed PP/Si3N4 composites created using material extrusion (MEX) 3D printing are examined. Thermogravimetric analysis and differential scanning calorimetry are exploited to study thermal stability and phase transitions in composite materials. Mechanical testing is conducted to determine mechanical qualities, such as flexural and tensile strength and modulus of elasticity. For detailed characterization of the nanocomposites, scanning electron microscopy, and Raman spectroscopy are also performed. The results provide insight into the impact of Si3N4 nanoparticles on the mechanical properties, thermal stability, and rheological behavior of PP/Si3N4 composites. The 2 wt% Si3N4 filler showed overall the best performance improvement (21% in the tensile modulus of elasticity, 15.7% in the flexural strength, and high values in the remaining properties assessed). The nanocomposite with the maximum Si3N4 loading of wt% showed a 33.6% increased microhardness than the pure PP thermoplastic, showing a promising wear resistance for the parts built with it. This research reveals the ability of Si3N4 ceramic nanoparticles to improve the mechanical characteristics of PP-based compounds produced by MEX 3D printing.Graphical

Studies of Labware Contamination during Lipid Extraction in Mass Spectrometry-Based Lipidome Analysis.

In lipidomic analysis, plasticware is increasingly being used for lipid extraction and other sample processing procedures over glassware. However, a systematic investigation of the consequences of plasticware use on mass spectrometry (MS)-based lipidome analysis is lacking. In this work, we present an analytical approach for detecting and comparing solvent and labware contaminants encountered in lipidomic workflows. It is shown that the contaminant profiles varied widely between microcentrifuge tubes from different manufacturers. The most suitable polypropylene tubes tested introduced 847 labware-originating contaminant m/z's when three different manufacturing batches were tested for Folch lipid extractions. Of particular concern is that 21 primary amide and fatty acid surfactants were introduced that were identical to biological endogenous lipids, 16 of which had not been previously reported as leachables from polypropylene materials. Alternatively, the use of borosilicate glassware and PTFE-lined screw caps introduced 98 different contaminant m/z's across three manufacturing batches tested for Folch extractions. Despite the overwhelming number of labware contaminants introduced, current databases and literature only facilitated the identification of 32 contaminants. To address the dearth of publicly available contaminant information, we provide a comprehensive labware contamination repository containing high-resolution m/z values, adductation information, retention times, and MS/MS spectra. This resource should prove to be valuable for researchers in detecting and distinguishing contaminants from analytes of interest. A companion paper presents a detailed study of how labware contamination can lead to ion-suppression effects on coeluting lipids and interference in the analysis of endogenous lipids, such as those from human sera.

The Impact of the COVID-19 Pandemic on the Amount of Plastic Waste and Alternative Materials in the Context of the Circular Economy

The COVID-19 pandemic was first reported on 31 December 2019, in Wuhan. Since then, the rapid spread of the virus has directly impacted various aspects of people’s lives, including culture, society, education, and the economy. The environment has also been affected, as the disposal of thousands of tons of single-use personal protective equipment has resulted in a significant increase in waste. The challenge was to create environmentally friendly materials for personal protective equipment. One of the alternatives to polypropylene materials is a biodegradable nonwoven produced using spun-bonded technology. The article discusses various physical and mechanical parameters, the biodegradation process, and the distribution of molar masses during the weeks of nonwoven biodegradation. Additionally, the paper presents the results of in vitro cytotoxicity tests conducted on the material. Biodegradable materials are a viable solution to the challenges posed by a circular economy.

Biosurfactant-capped CuO nanoparticles coated cotton/polypropylene fabrics toward antimicrobial textile applications

The global COVID-19 pandemic has led to an increase in the importance of implementing effective measures to prevent the spread of microorganisms. Consequently, there is a growing demand for antimicrobial materials, specifically antimicrobial textiles and face masks, because of the surge in diseases caused by bacteria and viruses like SARS-CoV-2. Face masks that possess built-in antibacterial properties can rapidly deactivate microorganisms, enabling reuse and reducing the incidence of illnesses. Among the numerous types of inorganic nanomaterials, copper oxide nanoparticles (CuO NPs) have been identified as cost-effective and highly efficient antimicrobial agents for inactivating microbes. Furthermore, biosurfactants have recently been recognized for their potential antimicrobial effects, in addition to inorganic nanoparticles. Therefore, this research’s primary focus is synthesizing biosurfactant-mediated CuO NPs, integrating them into natural and synthetic fabrics such as cotton and polypropylene and evaluating the resulting fabrics’ antimicrobial activity. Using rhamnolipid (RL) as a biosurfactant and employing a hydrothermal method with a pH range of 9–11, RL-capped CuO NPs are synthesized (RL-CuO NPs). To assess their effectiveness against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) microorganisms, the RL-CuO NPs are subjected to antibacterial testing. The RL-capped CuO NPs exhibited antimicrobial activity at much lower concentrations than the individual RL, CuO. RL-CuO NPs have shown a minimum inhibitory concentration (MIC) of 1.2 mg ml−1 and minimum bactericidal concentration (MBC) of 1.6 mg ml−1 for E. coli and a MIC of 0.8 mg ml−1 and a MBC of 1.2 mg ml−1 for S. aureus, respectively. Furthermore, the developed RL-CuO NPs are incorporated into cotton and polypropylene fabrics using a screen-printing technique. Subsequently, the antimicrobial activity of the coated fabrics is evaluated, revealing that RL-CuO NPs coated fabrics exhibited remarkable antibacterial properties against both gram-positive and gram-negative bacteria.

Impact of a nanofiltration system on microplastic contamination in Geneva groundwater (Switzerland)

Microplastics (MPs) have been observed in the oceans, fresh waters, karstic water and remote water bodies. However, little is known on groundwater contamination, which is a natural resource of utmost importance for millions of people and is often perceived as a reliable source of water. Moreover, nanofiltration is perceived as a reliable technology to remove contaminants from water. In this study, large sample volumes of a silty-sandy gravel aquifer and the corresponding nanofiltered water were analysed for the presence of MPs (> 20 µm) using Fourier transform infrared (FTIR) microscopy. Concentration in ground water was 8 ± 7 MPs/m3 and increased to 36 ± 11 MPs/m3 in nanofiltered water. All MPs had a maximum Ferret diameter lower than 500 µm. Size distribution of MPs was towards the small size class (20–50 µm). In groundwater, 33% of MPs were detected in the smallest size class (20–50 µm) and 67% in the 50–100-µm-size class. In comparison, around 52% of MPs in nanofiltered water were observed in the 20–50 µm size class. Moreover, 33% of the MPs observed in nanofiltered water were in the 50–100 µm size class and 15% in the 100–500-µm-size class. From a chemical point of view, different plastic polymers were identified in groundwater and in nanofiltered water, such as polypropylene (PP), polyvinyl chloride (PVC), ethylene (vinyl acetate) copolymer (EVA), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and other polymer materials (such as polystyrene-based copolymers, vinyl-based copolymers). Fibres were observed in all samples, but only a small number of fibres (near 1%) were identified as PP synthetic fibres in nanofiltered water. Furthermore, no clear difference of fibre concentrations was observed between groundwater (232 ± 127 fibres/m3) and nanofiltered water (247 ± 118 fibres/m3). Groundwater had extremely low levels of microplastics, and although the nanofiltration effectively removes suspended particulate matter, it slightly contaminates the filtered water with MPs.

Diagnosis and management of complications following pelvic organ prolapse surgery using a synthetic mesh: French national guidelines for clinical practice

Diagnosis and management of complications following pelvic organ prolapse surgery using a synthetic mesh: French national guidelines for clinical practice

Morphological adaptation of expanded vermiculite in polylactic acid and polypropylene matrices for superior thermoplastic composites

AbstractThe morphological transformation of expanded vermiculite (VC) during injection molding with brittle PLA and ductile PP polymers along with its positive and negative contribution to mechanical response is investigated. Polymer/VC mixtures with 30 wt. % VC are prepared by thermokinetic high shear mixing at 4000 rpm without any ex‐situ exfoliation agents or compatibilizers. Obtained composite mixtures are then injection molded onto three‐point bending and tensile test specimens. Performed mechanical tests suggested a significant increase in tensile (110%) and flexural modulus (112%) of PP30VC samples. Presented fractographic and morphological investigations suggested that the root cause of measured improved tensile (36%) and bending strength (26%) of PP is the fibrillation of VC associated with PP/VC interactions under high shear. A similarly increasing trend for tensile (147%) and bending modulus (137%) was observed for PLA30VC samples. Contrary to PP30VC, a decreasing pattern was present in the case of tensile (−40%) and bending strength (−13%) of PLA30VC. The root cause for such reduction is determined to be (i) in situ exfoliation of VC inside PLA matrix and transformation of VC into micrometer‐sized platelets; (ii) evaporation of trapped water/crystalline water in the interlayer region of VC which caused in situ degradation of PLA during manufacturing.Highlights Vermiculite‐loaded PP and PLA composites are produced at high shear. Composites have superior modulus compared to neat polymers. Fibrillation of platelet vermiculite is observed in only the PP matrix.

Mathematical simulation of damage detection for fighting athletes and equipment based on conjugated polymer development.

Traditional combat sports equipment usually uses synthetic materials, such as polyurethane and synthetic leather. Although these materials have a certain degree of strength and durability, they have poor flexibility and antibacterial properties, making it difficult to provide stable support and protection for athletes. In order to enhance the antibacterial properties and flexibility of sports equipment and reduce the risk of injuries to athletes, this article conducts in-depth research on the development of combat sports equipment using conjugated polymers. This article first selects polypropylene (PP) as the base material for sports equipment for combat athletes, and uses the gas phase polymerization method to prepare the material; then uses chitosan as an antimicrobial agent and uses the oxidative degradation method to prepare it; after that, this article coats the chitosan antibacterial agent on the prepared PP material, and uses a combination of dipping and calendering for antibacterial treatment; finally, this article uses the spunbond melt-blown composite method to fill and combine the top equipment of combat athletes to achieve the structural design of sports equipment. In order to verify the effectiveness of the equipment, this article conducted equipment performance testing and sports injury simulation. The results showed that the average diameter of the antibacterial zone of this sports equipment reached more than 1 mm, and in the injury risk test, the risk of athletes' joint and muscle injuries was reduced by 16.9% and 20.5% respectively. Research shows that developing combat sports equipment based on conjugated polymers can help reduce the risk of injury to athletes and improve the safety of combat sports.