Polypropylene Sheets Research Articles

Screening and Isolation of Polypropylene Degrading Fungi from Waste Dumping Site, Kolhapur, India

Polypropylene (PP) and other plastic wastes are found to accumulate in the environment, creating significant ecological issues. They are determined to be considered non-biodegradable, It has been established that once it enters the environment, it stays there permanently. The present investigation aims to biodegrade PP without physical treatment and exposing it to UV light and sunlight exposed to potential fungi isolated from the soil of solid waste dumping site based on 18SrRNA analysis and the isolated strains were identified as 98.54% similar to Cladosporium sp. The fungal strain was submitted with Gene Bank accession number ON024632 and registered as a Cladosporium halotolerans strain SUK PRAKASH. The degradation was performed for 8 months of incubation in the aqueous medium. The biodegradation of polypropylene FTIR spectroscopy was performed to further examine the sheets, and the results indicated that perhaps the bonds between the sheets were weakening and breaking. The biodegraded samples of without treated PP sheets, UV-exposed PP sheets, and sunlight-exposed PP sheets exhibit weight loss of 4.2%, 6.1%, and 8.6% respectively.

Three-Dimensionally Printed Polypropylene Sheets: Insights on Mechanical and Interface Shear Behavior

Three-Dimensionally Printed Polypropylene Sheets: Insights on Mechanical and Interface Shear Behavior

The influence of the hardened matrix machining parameters on the process and production cost of the polypropylene cutting jacket

The turning process is a type of conventional machining process that uses tools with defined geometry, intended to obtain surfaces per revolution with the aid of one or more single-cutting tools. The study focuses on the evaluation of the machining process through the experimental analysis in the machining process of the polypropylene sheet cutting sleeve, for the optimization of the process. The research had been carried out through the analysis of two processes, one in the existing process with the necessary machining parameters and the other by experiment analysis, for testing hypotheses, which establish relationships between cause and effect between variables. It was found that the conventional machining took a total processing time of 116 h, while the new machining design proposed in this study reduced the production time by 61%.

Investigation of Weld Forces and Strength of Friction Stir Welded Polypropylene

Friction stir welding (FSW) is an advanced joining technology specifically developed for welding materials that are difficult to weld (e.g. polymers). Over the last two decades, more and more research has been published on the applicability and development of the technique on polymeric materials. The aim of the present study is to investigate the applicability of the method for welding polymeric materials and to analyse the effect of the parameters of FSW. In the tests, 4 mm thick polypropylene sheets were welded by varying two welding parameters (tool speed (n) and feed rate (vf)) in four levels. Thus, a complete experimental design with 16 measurement points was created. During the welding process, the force components on the tool/workpiece were measured, from which the resultant welding force was calculated and the strength of the joints was characterized by tensile testing. The ratio of the tensile strength of the joints and the tensile strength of the material were used to characterise the process in terms of joint efficiency. During welding, the axial force component (Fz) was the dominant force value. The resultant forces (Fe) decreased with increasing n, while they increased with increasing vf. The tensile strength of the joint, and hence the bonding efficiency, improved with increasing n, while it deteriorated with increasing vf. The ratio derived from the ratio of n to vf was also analysed, with an increase in the ratio showing a decreasing trend in the resulting weld strength and an improving trend in the bonding efficiency.

In-situ observation of falling-weight impact damage in isotactic polypropylene sheet

Isotactic polypropylene (iPP) sheets were subjected to low-energy falling-weight impacts under various conditions. The elastic energy recovered during unloading gradually increases with increasing impact energy and reaches a fixed value, while the dissipated energy during the impact test increases monotonically. Whereas higher impact energy and repeated impacts result in enhanced whitening in an iPP sheet, the load–displacement curve is unaffected by impact repetition. The stress–strain curves of the impact-damaged iPP specimens indicate that these specimens retain high ductility irrespective of the impact energy and number of impacts. In addition, the striker impact did not affect the crystalline lattice of the original iPP. The impact damage solely induces the decrease in yield stress, suggesting impact in the crystalline phase. The yield stress gradually decreases with increasing impact energy and number of repetitions owing to accumulation of impact damage in the crystalline phase. The yield stress reaches a constant value after several repeated impacts, where the asymptotic value decreases with the impact energy. Because the drop of the yield stress increases with the impact energy, it is suggested that preferential fracture in the lamellar crystals takes place owing to fluctuation in the strength. Impact-induced voids with a size of approximately twice the long period are found by in-situ small-angle X-ray scattering. Partial fragmentation of the lamellar crystal into lamellar cluster units is suggested to be the microscopic origin of the impact damage.

Study on Fibre Reinforced Composites Developed by using Recycled Fibres from Garment Cut Waste

Garment cut wastes from apparel industries are used for various applications in various industries. Normally garment cut wastes and recycled fibres from garment cut wastes are used in textile, furniture, carpet, paper, automobile, construction, and agricultural industries in low mechanical performance applications. In this research, composites are developed by using recycled fibres obtained from garment cut wastes as reinforcement and with different types of matrices. Recycled fibres used as reinforcements are obtained from garment cut wastes of cotton, polyester and cotton/polyester fabrics to develop these composites. These composites are developed by using Epoxy resin, Kaolinite, Polypropylene sheet as matrices. Reinforcements and matrices have used in different compositions and combinations to develop these composites. The main advantages of this type of composites are to combine the different properties of different materials to obtain unique and high-performance material. Technical properties like thickness, mass per unit area, Tensile strength, Flexural strength, Impact strength, Water absorbency and Scanning Electron Microscope of developed composites were tested and analyzed. The outcome of the results demonstrates that many of the composite proportions with different blend, reinforcement and matrcies show superior mechanical performances when compare it with each other, and it can be recommended for many potential applications.

Research on improved gas‐assisted extrusion of plastic sheets based on time–temperature equivalence principle

AbstractBased on the time–temperature equivalence principle, the relationship between the melt relaxation time (MRT) and melt heating temperature (MHT) in an improved gas‐assisted extrusion (GAE) of a polypropylene (PP) sheet was investigated by numerical simulations. In the simulations, the MRT was varied and the inherent properties of the MHT were controlled using experimental methods. With an increase in MRT, the velocity in all directions, pressure drop, and shear rate of the melt increased; however, increasing the MRT does not always yield a positive effect on the GAE process of the melt. For instance, the melt velocity increased vertically at the die exit with MRT, resulting in an outward extrudate swell. In addition, the extruded product was intact when the melt was heated to 220°C, which verified the principle of time–temperature equivalence.

Fragmentation of nano- and microplastics from virgin- and additive-containing polypropylene by accelerated photooxidation

Plastic is ubiquitous in the environment, where it gradually weathers and fragments into nanoplastics (NPs) and microplastics (MPs); however, the weathering process and fragmentation rate are poorly understood. In this study, we quantitatively determined the abundances and size distributions of NPs and MPs produced from virgin polypropylene (PP) and additive-containing PP (PPa) sheets via photooxidation with water in a simulated sunlight chamber followed by vortexing. The fragmentation rate of PP and PPa were approximately 1.1 × 108 particles/cm2 and 1.0 × 108 particles/cm2, respectively, during 176 days of exposure in the chamber (corresponding to 2.7 years of exposure in an outdoor environment in the Republic of Korea). However, quadratic regression analysis of the relationship between total particles produced and exposure duration revealed that the PP fragmentation rate was faster than the PPa fragmentation rate after a sunlight exposure duration equivalent to 2.7 years. Furthermore, the mechanical stress of vortexing after photooxidation played an important role in the production of MPs; it had a smaller role in the production of NPs. The sizes of fragmented particles produced by photooxidation and mechanical stress followed a power law distribution, with a scaling exponent of α = 2.87 ± 0.15, which was similar to a three-dimensional fragmentation pattern. This study provides valuable insights into the weathering and fragmentation processes of plastics. Further studies on the environmental fate and impact of NP and MP production from plastic weathering and fragmentation, as well as the potential influence of plastic additives on these processes.

Effect of Adding Al2O3 on the Macrostructure of Friction Stir Welding Polypropylene Sheet

In this study, an experimental investigation has been carried out to determine the effect of alumina (Al2O3) addition in joining polypropylene. Polypropylene is a thermoplastic material used most as a non-metallic material. One of the joining methods that can be applied in Polypropylene is Friction Stir Welding (FSW). The use of Al2O3 as a filler is to modify the polypropylene matrix's properties to improve the joint's quality. The Al2O3 powder with 99 9% purity was inserted along the polypropylene plates in the groove. This research analyzed the role of adding Al2O3 and tool rotation speed concerning the joints' quality. The experiment was performed under different values of tool speed rotation (204 rpm, 356 rpm, 620 rpm, and 1140 rpm) and the presence or absence of the addition of alumina powder. Then, the joint's quality is visually observed by optical macroscopy at the top and cross-section view. From macroscopic observations, adding alumina could make the visual of the joint look better and result in minimum defects than the joint without alumina addition. Instead, the increasing tool speed rotation helped the distribution of alumina during the welding process.

Comparative analysis of gas-assisted extrusion of polypropylene sheet based on two types of gas intake

Abstract The formation of a stable gas layer is to have a significant effect on polymer gas-assisted extrusion (GAE). Previously, for vertical extrusion forming, the gap intake method was used, which tends to result in very short stabilization times for the gas layer. In this study, the effect of two gas intake modes was compared based on horizontal sheet extrusion. The results show that stabilization of the gas layer is easily achieved in the vertical gas-assisted die by introducing gas first. However, when using parallel die, the gas distributes the melt uniformly along the surrounding velocity and the gas layer can be stable for a long time. Moreover, disrupting the process sequence also makes it easy to achieve gas layer stability without affecting the tability of the gas layer in the subsequent extrusion. And, during low-speed extrusion, the flow inertia of the polymer melt is used to extend the flow channel of the gas-free–assisted section into the gas-assisted section to overcome the gravity of the polymer melt and smoothly extrude it in the parallel gas-assisted die. The parallel die can be considered for the production of GAE of daily profiles and can be used to improve quality.

Fabrication and characterization of woven and comingled nonwoven sheet polypropylene hybrid composite by recycling and alkali-treated jute waste fibers

Natural fiber reinforced hybrid composite materials, with their enhanced characteristics, represent the future of our advanced material search. Natural fibers are the substitute for synthetics because their less manufacturing cost, bio-degradable, easy availability, durability, resistance to environmental degradation, etc., makes them popular nowadays. This paper presents how jute fibers are recycled from various jute waste sources. After recycling, jute fibers are used to fabricate the hybrid composites. Two forms of recycled jute sheets are used to fabricate the composites that is, woven sheets and nonwoven comingled (jute and polypropylene) sheets. The NaOH treatment was performed on recycled jute sheets with different concentrations (0%, 2%, 4%, 6%, and 8%). The hybrid composites are made using three distinct fiber-polypropylene weight fraction ratios (50/50, 40/60, and 30/70), as well as five different stacking sequences. Mechanical parameters such as tensile strength, elongation (%), flexural strength, impact strength, and water absorption were evaluated. Among the five fabricated combinations, it is found that the combination of (40/60), (JJJ), with 2% NaOH treated fibers composite gives the maximum tensile and flexural strength, and the combination of (30/70) (CCC) with 2% NaOH treated fiber composites exhibits the maximum Impact strength. The combination of (50/50), and (CCC) with 2% NaOH treated fiber composite gives the maximum Elongation %, and the combination of (50/50), (JJJ), and 0% NaOH treatment yields the maximum water absorption. A relationship between fabric loading, tensile modulus, and flexural modulus and other relationship between chemical treatment and water absorption% has been established for JJJ laminated sheet which shows almost best properties among them. These assessments make them most valuable for a variety of sectors, including car, aircraft, marine, and building construction.

Investigation of the Properties of Polypropylene Sheets that Incorporate Okara

Investigation of the Properties of Polypropylene Sheets that Incorporate Okara

Development of a water-based functional additive by using isobornyl acrylate copolymer to improve ink-adhesion on untreated polypropylene surfaces: A comparative approach

The good barrier and hot-fill properties of polypropylene (PP) films and sheets make packaging industries advantageous. However, printing over a PP substrate is a major issue encountered in the packaging industry. The present study intends to prepare, characterise, and compare isobornyl acrylate (IBOA)-co-acrylic acid (AA) and isobornyl acrylate (IBOA)-co-methacrylic acid (MAA) based non-halogenated functional additives by using oil in water emulsion processes. The bornyl group of IBOA helps in enhancing molecular bonding with the polypropylene (PP) surface. The various properties of these synthesised functional additives were characterised using dynamic light scattering-particle size and zeta potential analysis, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermal gravimetric analysis (TGA), and gel permeation chromatography (GPC). The adhesion of these functional additive incorporated ink samples on different untreated PP surfaces was compared using the cross-cut adhesion test. The methacrylic acid based functional additive shows better adhesion properties as compared to acrylic acid.

When the Beetles Hit the Fan: The Fan-Trap, an Inexpensive, Light and Scalable Insect Trap under a Creative Commons License, for Monitoring and Experimental Use.

Monitoring is an important component in pest management, to prevent or mitigate outbreaks of native pests and to check for quarantine organisms. Surveys often rely on trapping, especially when the target species respond to semiochemicals. Many traps are available for this purpose, but they are bulky in most cases, which raises transportation and deployment issues, and they are expensive, which limits the size and accuracy of any network. To overcome these difficulties, entomologists have used recycled material, such as modified plastic bottles, producing cheap and reliable traps but at the cost of recurrent handywork, not necessarily possible for all end-users (e.g., for national plant-protection organizations). These bottle-traps have allowed very large surveys to be conducted, which would have been impossible with standard commercial traps, and we illustrate this approach with a few examples. Here, we present, under a Creative Commons BY-SA License, the blueprint for a fan-trap, a foldable model, laser cut from a sheet of polypropylene, which can rapidly be produced in large numbers in a Fab lab or by a commercial company and could be transported and deployed in the field with very little effort. Our first field comparisons show that fan-traps are as efficient as bottle-traps for some Scolytinae species and we describe two cases where they are being used for monitoring.

Polyaniline-polycaprolactone electrospun nanofibrous mat: new polymeric support with anion exchange characteristic for immobilizing liquid membrane in efficient on-chip electromembrane extraction of polar acidic drugs.

The potential of application of an electrospun nanofiber sheet as new polymeric support for immobilizing the liquid membrane, instead of a common commercial polypropylene sheet, in on-chip electromembrane extraction (EME) of some acidic polar drugs followed by HPLC with ultraviolet detection is presented. The nanofiber sheet was prepared by electrospinning a mixture of polycaprolactone and polyaniline. The successful synthesis of the electrospun nanofiber sheet was confirmed by field emission-scanning electron microscopy, energy-dispersive X-ray spectroscopy, elemental mapping, and atomic force microscopy. Several parameters affecting the efficiency of the microextraction method, including pHs of the donor and acceptor phases, applied voltage, sample flow rate, phosphate content of the acceptor phase, and sample volume, were investigated and optimized. After optimization, the linearity range of 0.5-250.0µg L-1 and detection limits of 0.2-1.0µg L-1 were obtained for the analytes. The extraction recovery values and preconcentration factors were 10.7-55.3% and 16-83, respectively. The presence of polyaniline in the composition of the nanofibers significantly improved the extraction efficiency of the polar acidic drugs due to providing the possibility of various interactions with the target analytes such as hydrogen bonding, π-stacking, andanion exchange. The obtained results demonstrate the excellent efficiency of the synthesized electrospun nanofibrous mat as a novel support membrane for immobilizing 1-octanol and as an interactive substrate for electromembrane extraction of acidic polar drugs. Eventually, the proposed on-chip EME method exhibits acceptable precision (relative standard deviations less than 9.7% (n = 3)) and good accuracy (86-112%) for determining the target analytes in the plasma samples.

Liquid Metal-Templated Tin-Doped Tellurium Films for Flexible Asymmetric Pseudocapacitors.

Liquid metals can be surface activated to generate a controlled galvanic potential by immersing them in aqueous solutions. This creates energized liquid-liquid interfaces that can promote interfacial chemical reactions. Here we utilize this interfacial phenomenon of liquid metals to deposit thin films of tin-doped tellurium onto rigid and flexible substrates. This is accomplished by exposing liquid metals to a precursor solution of Sn2+ and HTeO2+ ions. The ability to paint liquid metals onto substrates enables us to fabricate supercapacitor electrodes of liquid metal films with an intimately connected surface layer of tin-doped tellurium. The tin-doped tellurium exhibits a pseudocapacitive behavior in 1.0 M Na2SO4 electrolyte and records a specific capacitance of 184.06 F·g-1 (5.74 mF·cm-2) at a scan rate of 10 mV·s-1. Flexible supercapacitor electrodes are also fabricated by painting liquid metals onto polypropylene sheets and subsequently depositing tin-doped tellurium thin films. These flexible electrodes show outstanding mechanical stability even when experiencing a complete 180° bend as well as exhibit high power and energy densities of 160 W·cm-3 and 31 mWh·cm-3, respectively. Overall, this study demonstrates the attractive features of liquid metals in creating energy storage devices and exemplifies their use as media for synthesizing electrochemically active materials.

Crosspolarization with imperfect infrared polarizers

The analysis of vibrational bands is a core application of infrared (IR) spectroscopy. Polarization-dependent measurements enable the study of anisotropic materials. However, imperfect IR polarizers exhibit polarizer leakage, which causes pronounced bandshape and baseline distortions for samples with weak optical anisotropy. Based on the 4 × 4 Mueller-matrix formalism, we propose a polarimetric measurement scheme for handling imperfect polarizers and source prepolarization that delivers correct co- and crosspolarized transmission and reflection IR spectra. The scheme is applied to a weakly anisotropic polypropylene sheet, resolving crosspolarized signatures as small as 5⋅10−5. We determine the polymer’s direction-dependent complex refractive index in the vibrational fingerprint range.

Solar Energy Driven Membrane Desalination: Experimental Heat Transfer Analysis

In the direct contact membrane distillation (DCMD) system, the temperature polarization due to boundary layer formation limits the system performance. This study presents the experimental results and heat transfer analysis of a DCMD module coupled with a salinity gradient solar pond (SGSP) under three different flow channel configurations. In the first case, the feed and permeate channels were both empty, while in the next two cases, the feed and permeate channels were filled with a porous spacer material. Two different spacer geometries are examined: 1.5 mm thick with a filament angle of 65°, and 2 mm thick with a filament angle of 90°. The study considers only the heat transfer due to conduction by replacing the hydrophobic membrane normally used in a DCMD module with a thin polypropylene sheet so that no mass transfer can occur between the feed and permeate channels. The Reynolds number for all three configurations was found to be between 1000 and 2000, indicating the flow regime was laminar. The flow rate through both the feed and permeate sides was the same, and experiments were conducted for flow rates of 5 L/min and 3 L/min. It has been found that the highest overall heat transfer coefficient was obtained with the spacer of 2 mm thickness and filament angle of 90°.

Fabrication of Mucoadhesive Films Containing Pharmaceutical Ionic Liquid and Eudragit Polymer Using Pressure-Assisted Microsyringe-Type 3D Printer for Treating Oral Mucositis.

Oral mucositis in the oral cavity, caused by radiation therapy and chemotherapy, requires personalized care and therapy due to variations in the lesions of patients. In the present study, we fabricated a model of personalized oral film containing an ibuprofen/lidocaine ionic liquid (IL) for patients with oral mucositis using a pressure-assisted microsyringe-type 3D printer at room temperature. The film contained a Eudragit polymer (L100, EPO, or RSPO) to make the film solid, and the printer ink was composed of organo ink (organic solvent to dissolve both drugs and the Eudragit polymer). The viscosity of the printer ink was assessed to investigate its extrudability. The contact angle and the surface tension at the interface between each liquid printer ink and a solid polypropylene sheet were measured to determine the retention of the ink in 3D printing. The physical properties of IL-loaded Eudragit-based dry films were examined by X-ray diffraction and differential scanning calorimetry. Dissolution tests indicated that IL-loaded films containing a Eudragit polymer exhibited different drug release rates in phosphate buffer (pH 6.8; Eudragit L100 > IL alone > Eudragit EPO > Eudragit RSPO). These results provide useful information for the specific fabrication of IL-loaded polymer-based films using organo inks and pressure-assisted microsyringe-type 3D printers.

Investigation on the Structure and Performance of Polypropylene Sheets and Bi-axially Oriented Polypropylene Films for Capacitors

Investigation on the Structure and Performance of Polypropylene Sheets and Bi-axially Oriented Polypropylene Films for Capacitors