Thermoplastic Polymer Materials Research Articles

Evaluation of gamma-ray attenuation characteristics of some thermoplastic polymers: Experimental, WinXCom and MCNPX studies

In this work, the γ-ray attenuation properties of some thermoplastic polymers as widely used materials in nuclear medical diagnosis and treatment have been studied. The mass attenuation coefficient (μm) of all selected polymer samples have been measured using NaI (Tl) detector, WinXCom Program and MCNPX simulation at photon energies 122-1332 keV. Further, μm values were used to estimate other related parameters including linear attenuation coefficient, total molecular, atomic, and electronic cross-sections, effective atomic number, effective electron density, relaxation length, HVL and TVL. Results show that the theoretical and simulation values of attenuation parameters are in satisfactory agreement with experimental results. However, the experimental values of μm have been found to be closer to those calculated by MCNPX than the values obtained by WinXCom. In addition, the effectiveness of well-known thermoplastic polymer materials in nuclear medicine application at different photon energies has been compared and discussed.

3D-printed and injection molded polymer matrix composites with 2D layered materials

Two-dimensional layered materials (2DLMs), MoS2 and WS2, and three-dimensional (3D) graphite were infused in thermoplastic polymer matrices comprised of acrylonitrile butadiene styrene (ABS) and polyethylene terephthalate glycol (PETG). Two processing approaches were examined for creating polymer tensile test specimens using the composites for mechanical testing, which included three-dimensional (3D) printing and injection molding. The ductility generally decreased with the addition of the fillers indicated by an increase in Young’s modulus and a corresponding decrease in yield stress and tensile stress for the 2DLM-polymer composites. The dynamic friction data of the composites were measured in an attempt to exploit the solid phase lubricating properties of graphite and the 2DLM fillers. Graphite proved to lower the dynamic friction in the cases of 3D printed PETG and injection molded ABS, while MoS2 and WS2 were found to reduce friction in 3D printed PETG and ABS. Finally, the thermal conductivities of these polymer matrix composites were measured and compared to the pure polymer matrices. The thermal conductivity increased in both ABS and PETG composites containing graphite, MoS2, and WS2, irrespective of their processing routes. The use of 2DLM-based polymer composites remains an area of interest for a wide range of applications in the future, such as wearable electronics and sensors with low-cost additive manufacturing approaches.

Progress of Bio-Calcium Carbonate Waste Eggshell and Seashell Fillers in Polymer Composites: A Review

Disposal of massive amounts of eggshells and seashells from processing industries is a challenge. In recent years, there has been a focus to reuse these waste resources in the production of new thermoplastic and thermoset polymer materials. This paper reviews eggshell and seashell production by country and provides a perspective on the quantity of bio-calcium carbonate that could be produced annually from these wastes. The achievements obtained from the addition of recycled bio-calcium carbonate fillers (uncoated/unmodified) in polymer composites with a focus on tensile strength, flexural strength and impact toughness are discussed. To improve compatibility between calcium carbonate (mineral and bio-based) fillers and polymers, studies on surface modifiers are reviewed. Knowledge gaps and future research and development thoughts are outlined. Developing novel and innovative composites for this waste material could bring additional revenue to egg and seafood processors and at the same time reduce any environmental impact.

A Study on The Application of Convoluted PTFE For Arterial Implantation: Mechanical Testing and Properties

Polytetrafluoroethylene (PTFE) is a thermoplastic polymeric material with various applications including aerospace, automotive, biomedical and electrical. PTFE surface is smooth, wear resistant, non-sticky and slippery in nature. Combined with such useful properties, the material conveys various other features such as temperature resistance up to 260°C, exceptional chemical stability, corrosion resistance, good fatigue strength and sterilisable. This work involved mechanical testing of convoluted PTFE tubes with different thicknesses, diameters and lengths. This included the following tests: volumetric expansion, tensile and elongation, rolling u wear and burst tests by applying real industrial pressures. The mechanical testing showed promising results for the convoluted PTFE tubes which could undergo extreme elongation due to the elastic nature. The % volumetric expansion exceeded the expected values (on average, 3-5% higher than the expected values). The results for the rolling u wear, burst and tensile tests also showed good properties. Based on its mechanical properties, convoluted PTFE seemed to be an appropriate material for replacing damaged/diseased arteries.

Rotomolding and polyethylene composites with rotomolded lignocellulosic materials: A review

Rotomolding is a versatile process used in the manufacture of thermoplastic polymeric materials to produce large hollow plastic parts. The aim of this review article was to discuss the rotomolding process and show the properties of the polyethylene composite and rotomolded lignocellulosic fibers, which are processed for prolonged periods under temperature. The main process parameters studied are the shaft speed of the equipment, molding temperature, polymer particle size, polymer melt flow index, and amount of material, which must be well controlled to achieve a non-degraded product with homogeneous thickness and no porosity. Rotomolded composites containing sisal, pine, coir, banana, flax, and maple wood fibers, among others, have been evaluated primarily for their mechanical (impact, flexural, and tensile strength) and morphological properties. The type, content, and treatment of lignocellulosic fillers are the most widely studied variables in polyethylene-based rotomolded composites. Fiber content was the variable that most influenced mechanical properties, particularly impact strength and hardness due to the voids formed by the hydrodynamic volume between the polymer matrix and lignocellulosic filler. Chemical treatment of the fiber by mercerization with NaOH made it more hydrophobic and the addition of maleic anhydride-grafted polyethylene as a coupling agent improved the interfacial adhesion between the non-polar polymer matrix and polar filler. However, the best mechanical property results were obtained with the use of maleic anhydride-grafted polyethylene.

Analysis of structural features and efficiency of application of modern FDM printers for 3D printing using polymer thermoplastic materials

This work presents the main parameters of the current state of the world market of additive manufacturing equipment. For research, the most common type of additive technology was chosen, namely FDM (Fused Deposition Modeling) or 3D printing using thermoplastic polymer material. This technology is the most common and is used in industry, engineering design, rapid prototyping, educational process, scientific research, medicine, design and the like. The main works were presented that consider the main characteristics of the equipment, systematize them according to design features and areas of application. Given the insufficient coverage of equipment types and designs in these works, an extensive review of devices based on FDM technology was carried out. The classification of equipment is based on the principle of moving executive bodies, namely the print head and the 3D printer working platform. Based on this, it has been established that there are four main schemes for constructing of 3D printers such as Cartesian, Delta, Polar and schemes based on a robotic manipulator. The most popular models of 3D printers for each of the circuits were given, their main advantages and disadvantages, areas and applications, examples of products manufactured were considered. The review showed that the most widespread in the scheme both in the world and in Ukraine is the Cartesian, which in turn is divided into a number of subspecies. Among them, Prusa, CoreXY and H-Bot schemes are especially popular. They are the most versatile, use almost all types of consumable thermoplastic material, include almost all the range of sizes needed for production of the working area and are the most flexible for modernization. FDM 3D printers based on a robotic arm were also noted. The development of this type of equipment is an example of the introduction of additive technologies in serial automated production. Consideration of the main areas of application and the main advantages and disadvantages of each of the types of 3D printers made it possible to give recommendations on the choice of equipment for spatial printing, depending on the type of activity.

Carbon fiber/poly ether ether ketone composites modified with graphene for electro-thermal deicing applications

Carbon fiber/poly ether ether ketone (Cf/PEEK) composites are a class of high performance, continuous fiber reinforced thermoplastic polymer materials. These composites have the potential to meet demands for self-cleaning or deicing applications in the power supply industry in cold regions. In this study, the effect of graphene on the deicing performance of Cf/PEEK composites through electro-thermal Joule heating was investigated. First, graphene/PEEK composites with varying graphene content of up to 6 wt% were fabricated and characterized. Adding up to 5 wt% graphene was found to improve the electrical conductivity, thermal conductivity, and the crystallinity of PEEK. However, at a graphene content of 6 wt%, the crystallinity and thermal conductivity of the mixture decreased, likely due to agglomeration of graphene. Next, graphene modified Cf/PEEK composites (0 and 5 wt% graphene) with resin volume fractions of 40, 50, and 60 vol% were prepared by hot pressing. Graphene was found to increase the electrical conductivity of the composites by roughly 100%, and to improve the efficiency of converting Joule heating to useful deicing energy by up to 35%.

Mechanical and Tribological Performance of Polymer Composite Materials: A Review

This paper reviews the effects of various reinforcements with the various thermoplastic polymer matrices. The articles contain the various thermoplastic polymers such as ABS, HDPE, LDPE, PP, PEEK, PC, PA, PI, UHMWPE and PMMA etc. The review contains the evaluation of tribological properties such as sliding wear and coefficient of friction (COF) of polymer matrix composites (PMCs). This review also evaluation of mechanical properties such as tensile strength, compressive strength, young modulus and hardness of polymer matrix composites (PMCs). The thermoplastic polymer composite used in various applications such as automotive industry, food processing machine industry, household appliance, military, structural and aerospace industry etc. The properties of thermoplastic polymer composite are varying with the fabrication techniques of composite.

Effect of nanoclay inclusion on mechanical and fatigue behavior of ABS/PP/HDPE thermoplastics

Thermoplastic Polymer materials are replacing conventional metals in the usage of commodities owing to their high specific properties. Due to their low mechanical properties and poor fatigue performance their usage is restricted in engineering applications. In the present study three variety of thermoplastic polymers Polypropylene (PP), High-density polyethylene (HDPE) and Acrylonitrile Butadiene Styrene (ABS) were considered and reinforced with nanoclay and their mechanical and fatigue behavior were tested. Results dictates that reinforcement of nanoclay improves their mechanical properties and fatigue performance considerably.

A comparative study on drilling performance of hydroxyapatite-polycarbonate and hydroxyapatite-polysulfone composites using principal component analysis methodology for orthopaedic applications

Composite materials including man made Hydroxyapatite (HAp) and synthetic thermoplastic polymer matrices have become popular choice in replacement of broken or repair of harmed part of a bone by artificial bone materials in the human body. HAp is the best ceramic material for orthopedic applications due to its superior biocompatibility and bonding properties. In this study polycarbonate (PC) and polysulfone (PSU) polymer matrices are taken to mix with HAp material. As drilling is required to join the composite material with adjacent bone tissue in orthopaedic surgery, it is necessary to identify drilling performance of the composites. Investigations have been performed on a CNC milling machine by availing Taguchi’s L27 orthogonal array design with four input factors such as HAp volume percentage, drilling speed, feed rate and drill bit diameter (each at three levels), and the expected output responses considered are circularity at entry and exit, torque and thrust force. The circularity at both entry and exit is determined by using the ratio of minimum diameter (Dmin) to maximum diameter (Dmax) of the drilled hole, whereas the torque and thrust force is measured using drill dynamometer. Best parametric setting for simultaneous optimization of multiple performance measures such as circularity at entry, circularity at exit, torque and thrust in drilling operation is suggested using principal component analysis.

IR Artificial Compound Eye

AbstractIn this work, a 3D IR artificial compound eye (ACE) optical component is fabricated using thermoplastic IR polymer material. The femtosecond laser‐assisted wet etching and the 3D nano‐imprinting techniques are proposed for fabricating this thin shell multi‐aperture component. The prepared component is close‐packed with over 1000 high‐quality micro‐facet‐lenslets (ommatidia) on the semispherical thin shell dome with base radius of 2.7 mm and sag height of 2.1 mm, enabling enlarged field of view to 148°. The ommatidia with diameter of 150 µm and numerical aperture of 0.35 are demonstrated to have a practical spatial resolution up to 160 lp mm−1. IR imaging experiments (both in passive and active scenarios) confirm its outstanding optical properties and uniformity, and demonstrate the probability of thermal target imaging with such component in the near‐infrared band. The proposed fabrication strategy shows remarkable efficiency and advantage in massive replication, and such ACE component predicts its potential in emerging applications, such as IR imaging, target tracking, and so on.

Use of Nanoparticles of a Finely Dispersed Silicon Carbide Obtained in an Electrothermal Boiling Bed as a Structural Modifier of Thermoplastic Polymers

Porous powders of a finely dispersed silicon carbide obtained as a result of the carbothermal reduction of silica in an electrothermal boiling-bed reactor were investigated. It was established that such a powder comprises silicon-carbide nanoparticles of size ~50–70 nm and filametry formations of these nanoparticles with an aspect ratio of ~5–15. It is shown that the silicon-carbide nanoparticles introduced in a thermoplastic polymer interact with its matrix and, in so doing, change the polymer structure, with the result that a composite material is formed. Such thermoplastic polymer composites possess enhanced physical, mechanical thermal, and thermophysical properties. New heat-conducting polymer composite materials having a high wear resistance and good antifriction properties have been developed. These materials can be used in machine building as protective coatings, members, and units of facilities operating in the regime of abrasive wear, in power and electrical engineering, and in microelectronics where there is a need for heat-conducting thermoplastic polymer materials.

Reconstruction of craniofacial defect using individualized implant

Background: The procedure of cranioplasty has numerous indications, and the main objective is to support the underlying noble structures, returning original shape and aesthetics. The current treatment of choice is controversial related to the type of material to be used. Polyetherketone (PEEK) is a thermoplastic polymer material with high mechanical properties, with intraoperative adjustment rates close to titanium. 1 Lethaus B. et al. A treatment algorithm for patients with large skull bone defects and first results. Journal of Cranio-Maxillo-Facial Surgery. 2011; 39: 435e440 Crossref Scopus (59) Google Scholar

A study of the transient shear flow behavior of the incompressible and isothermal thermoplastic polymer materials

In this article, a feasible mathematical method was proposed to describe the instantaneous shear flow behavior of the incompressible and isothermal thermoplastic materials. Based on the molecular kinetics, thermodynamics, and continuum mechanics method, a viscoelastic model was presented about the intricate rheological phenomena of polymer macromolecules, which is simplified as the generalized Newton’s law. The rheological experiments were carried out with the isotactic polypropylene material. The analysis of variance method was performed to determine the fitness of the model. By comparing with the Ostwald–de Waele power law model and Cross model, the theoretical model was studied. The experimental results reveal that the theoretical model is more accurate than the Ostwald–de Waele power law model and shows a roughly equivalent fitness with the Cross model, which indicates that the theoretical model is effective and robust. Moreover, the results of this study may have potential industrial applications and benefit the users of certain plastic components.

Komposit Gentian Kenaf: Satu Ulasan bagi Sintetik dan Biodegradasi Polimer Matrik

This review paper deals with the previous and current works published on the kenaf fiber composites. Kenaf is grown commercially in South East Asia country and widely used in the construction and infrastructure as well as in the automotive industry. Kenaf fiber is usually reinforced with synthetic based polymer resin such as polypropylene. However, recent studies tend to concern towards the environmental issues which kenaf fiber act as an alternative natural fiber competitor. Moreover, the combination of the natural fiber and the biodegradable polymer able to reduce the negative impact on human health. Hence, researcher-initiated the interest focusing on the biodegradable materials obtained from the renewable sources. A huge attention gave to the kenaf fiber reinforced bio-polymer materials such as polylactic acid. The processing technique and the fiber orientation within the composite materials are discussed extensively in order to obtain the maximum composite performance. Results indicated that the mechanical properties; tensile strength and tensile modulus, are improved as the kenaf fiber was aligned in uni-direction. Therefore, this paper overview on the kenaf retting types in the common form of kenaf fibers and discussing the thermoplastic polymer matrices types used in the fabrication processes. In addition, the challenging of using kenaf fibers composites and its application in the automotive industry also highlighted.

Post-fabrication modifications of thermoplastic polymeric nanofiber membranes with electroactive polymers for triboelectric nanogenerators

With the development of wearable electronics, the demand for sustainable power supply has propelled the growth of garment-based triboelectric nanogenerators (TENGs). New approaches which can improve the electrical output performance while ensuring the comfort of wearing from a device are ongoing. In this investigation, a high-performance contact-separation TENG has been constructed with two triboelectric layers using the same thermoplastic polymeric materials. The above thermoplastic polymeric materials which are raw materials of clothing are used as substrate after developing them into nanofibers via melt-blending extrusion method. Post-fabrication modifications are applied to nanofiber membranes to achieve tribo-electronegative and tribo-electropositive for increasing the performance in terms of electrical output from the obtained devices. Driven by periodic motions, the triboelectric pair containing PTFE/PVDF/EVOH composite nanofiber membranes (PPECNMs) fabricated via facile non-solvent induced phase inversion and PEI/EVOH composite nanofiber membranes (PEI-ECNMs) obtained through effective grafting reaction realizes a continuous contact and separation to achieve a remarkable power density of 2.45 W/m2. In addition, the possibility of the developed TENG to harvest frictional energy between garment triggered by the body motions is successfully proved by sewing the triboelectric pair on clothes because of the compatibility between thermoplastic polymeric materials and clothing. Consequently, this study not only provides a novel way for the modification of micro-nanostructural triboelectric layers, but also demonstrates the practicality of all-fiber devices towards applications in smart garment.

A Theoretical Study on Transitional Shear Flow Behavior of the Compressible and Isothermal Thermoplastic Polymer

By extending the virtual conformational element of the polymer chain, a dynamic end-to-end (ETE) vector was presented to describe the chain’s instantaneous morphology based on the spring-bead theory. A feasible viscoelastic model was proposed to describe the rheological behavior of the isothermal thermoplastic polymer materials, based on the molecular kinetics, thermodynamics, and continuum mechanics method. The model is simplified as the generalized Newton’s law. Its integral formula with similar form to the KBKZ model was also derived. Rheological experiments were carried out with the isotactic polypropylene material. The experimental results reveal that the viscoelastic model exhibits a three-stage rheological characteristic. There is a distinct high-elastic rheological region in the middle stage, reflecting the pseudoplastic fluids properties. Compared with the Ostwald-de Waele power law model, the viscoelastic model shows a better agreement with the rheological practices.

Investigation on Thermal and Tribological Properties of Polypropylene/Spheri Glass 3000 Composites Processed by Melt Intercalation Method

The polymer composites show a remarkable improvement in their properties when compared to the virgin thermoplastic polymer materials, and it finds its application in several fields. In the current research work Polypropylene (PPE) was chosen as a thermoplastic matrix and Spheri Glass 3000 (SG3) as the filler. The SGE was added at 0, 1.25, 2.5 and 5 wt.% to PPE matrix. The processing of PPE and PPE/SGE was done using a twin screw extruder. Injection moulding was used for producing the test specimens. The processed PPE/SGE composites were characterised by X-ray diffraction, dispersion studies density, Melt Flow Index (MFI), Heat Deflection Test (HDT) and abrasive wear tests. The abrasive wear test by means of two-body abrasive test was carried out with input factors like (i) sample (0, 1.25, 2.5 and 5 wt.%), (ii) applied load (10, 20, 30, 40 N) and (iii) sliding velocity (0.5, 1.0, 1.5 and 2.0 m/s) under a constant sliding distance of 500 m. The influencing factors of the two-body abrasive wear tests were studied by Analysis of Variance (ANOVA). Finally, the worn surface morphology of the abraded surface was studied using a Scanning Electron Microscope (SEM).

Parametric Study of the Mechanical Behavior of FSSW Welded Polymer Plates Using a New Form of Welding Tool

This research paper aims at studying the friction stir spot welding (FSSW) some of thermoplastic polymer materials (HDPE and HDPE-PMMA) using a specifal geometry tool without a pin. The effect of the tool geometry on the welds static resistance was studied via several tool shape, a flat shape below the tool, a shape with concavity angles ranging from 0° to 16° , a flange shape of the sharp-edged tool, a chamfered flange shape and a rounded shape. This work is done to increase the surface area of the weld and further to maximize the static strength of the friction stir spot welding. Experimental tests have been carried out under various operational parameters such as the tool rotation speed, tool plunge depth and dwell time. This later has been carried out to highlight the effect of the tool’s geometry and the operational parameters of the welding on the surface in virtue on static resistance of the friction stir spot welding of thermoplastic polymers. Tests of lap-shear at speed of 5m/s have showed that the tool geometry plays a very important part. This study shows that a FSSW welding tool with 4° concavity angle tool and a rounded flange shape gives the best welding quality for the polymers studied.

Preparation and Characterization of Poly(butylene succinate)/Polylactide Blends for Fused Deposition Modeling 3D Printing.

To obtain a new type of biodegradable material with high toughness and strength used for fused deposition modeling (FDM) printing, a series of poly(butylene succinate) (PBS)-based polymer materials was prepared via blending with polylactide (PLA). The rheological, thermal, and mechanical properties as well as FDM printing performances of the blends, such as distortion, cross section, and the interlayer bond strength, were characterized. The results show that with increasing PLA content, the blends possess higher melt viscosity, larger tensile strength, and modulus, which are more suitable for FDM printing. Especially, when the content of PLA is more than 40%, distortion due to residual stress caused by volume shrinkage disappears during the printing process and thus products with good dimensional accuracy and pearl-like gloss are obtained. The results demonstrate that the blend compositions with moderate viscosity, low degree of crystallinity, and high modulus are more suitable for FDM printing. Compared with the low elongation upon breaking of commercially FDM-printed material, the PBS/PLA blend materials exhibit a typical ductile behavior with elongation of 90–300%. Therefore, besides biodegradability, the PBS/PLA blends present excellent mechanical properties and suitability as materials for FDM printing. In addition, our study is expected to provide methods for valuating the suitability of whether a thermoplastic polymer material is suitable for FDM printing or not.