Self-healing polymers based on the novel damage management concept were introduced several years ago. Since then different concepts have been successfully developed. However, the analysis and characterization of the self-healing process represents still a significant challenge, in particular for the quantification of scratch healing. Consequently, the comparability of the reported healing efficiencies

With the goals of reducing negative environmental impacts and improving the novel food packaging industry, edible films composed of Chinese yam mucilage (DOM) and starch were prepared via a casting method. The films were characterized by analysing the physical, morphological, mechanical and barrier properties, performing a thermal analysis, and finally performing an acute toxicity analysis in rats

Hindered amine light stabilizers are used to protect polymers from heat- and light-induced degradation. In this study the oligomeric stabilizer Tinuvin 622 was analysed in-depth employing high performance liquid chromatography/time of flight mass spectrometry (HPLC/TOF-MS) to differentiate products of different manufacturers in respect of their terminating groups and oligomer length. Additionally,

Designing advanced biomaterials with regenerative and drug delivering functionalities remains a challenge in the field of bone and tissue engineering. In this paper we present the design, development, and a use case of an electrospun nano-biocomposite scaffold composed of silk fibroin (SF), hardystonite (HT), and gentamicin (GEN). The fabricated SF nanofiber scaffolds provide mechanical support while

Due to its low cost and high efficiency, injection molding is used for the mass production of many plastic products nowadays. However, when processing low-viscosity plastic materials, i.e., materials with an excellent fluidity, an inappropriate setting of the clamping force often results in a poor appearance and dimensional accuracy of the final product. Thus, operators usually take the upper limit

Transparent optically anisotropic substrates (TOASs) are a crucial component in flexible electronics. Moreover, knowing the deflection radii of TOASs is essential to estimate the residual stresses of the thin films deposited on them. This paper proposes a novel measurement method to measure the deflection radii of polyimide (PI) substrates. Red, green, and blue filters and a circularly polarized system

A combination of knowledge on curing process of rubber mixes with novel methods of chemical analysis, a new unconventional approach to analysis of rubber vulcanization is presented in this study. Six SBR samples containing various N-tert-butyl-2-benzothiazole sulfenamide (TBBS) accelerator: sulfur ratios (within) the range of conventional (CV) sulfur vulcanization system were studied using multi-capillary

In the present work, microfibrillated cellulose (MFC) suspensions were produced by high-pressure homogenization and subsequently used to fabricate MFC membranes (C-1) by vacuum filtration followed by hot-pressing. A polyketone (PK50) was chemically modified by Paal-Knorr reaction to graft imidazole (IM) functional groups along its backbone structure. The resulting polymer is referred to as PK50IM80

Rigid polyurethane foams were manufactured using rapeseed oil-based polyol with hydroxyl number 270 mg KOH/g (10 wt% - 50 wt%) and ground egg shell waste as a natural filler (20 php) in a single-step synthesis procedure. The goal of the study was the investigation of the influence of renewable raw materials on the structure and physico-mechanical, thermal and biological properties of the final foams

UHMWPE viscoelastic fibers show great interest as reinforcement within composites and especially when used in SRPs (Self-Reinforced Polymers). They provide ductility, lightness and recyclability, benefits that glass or carbon fibers cannot provide. It is, therefore, necessary to increase knowledge about the behavior of UHMWPE fibers. Before the thermomechanical characterization of these yarns, an experimental

Microstructures of poly (ethylene-co-vinyl acetate) (EVA) are dependent on the distribution of VA units as well as the VA content. Simple analytical method to determine microstructure of EVA was established using melting points of EVA and correlationship with those of wax and its ester. EVAs with the VA contents of 9.5–40 wt% (3.3–17.8 mol%) were used. The melting points were analyzed using differential

This research aims to develop superhydrophilic fiberglass/epoxy nanocomposite (FGEC) laminates with high mechanical, thermal, and impact properties. In order to achieve this goal, functionalized graphene (FGA) was used as a nanofiller material to improve the mechanical, impact, and thermal behaviors of FGEC, while the plasma treatment helped to form the oxidized polar functional groups (C9O groups

Stress concentration and weak interfacial strength affect the mechanical properties of short carbon fibers (CFs) reinforced polymer composites. In this work, the cauliflower-like short carbon fibers (CCFs) were prepared and the point was to illuminate the effects of fiber morphology on the mechanical properties of the CCFs/rigid polyurethane (RPU) composites. The results indicated that the surface

Additive manufacturing offers a useful and accessible tool for prototyping and manufacturing small volume functional parts. Polylactic acid (PLA) and thermoplastic polyurethane (TPU) are amongst the most commonly used materials. Characterising 3D printed PLA and TPU is potentially important for both designing and finite element modelling of functional parts. This work explores the mechanical properties

In this study, polyvinylidene difluoride (PVDF) is doped with different volume levels (10, 20, 30 vol %) of lead zirconate titanate (PZT), and neat PVDF (undoped) electrospun nanofibres are prepared by aligning them through the electrospinning process with a rotating drum collector. All of the produced nanofibres are characterized by X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM)

In the present decade, the demands for recyclable, environmentally friendly and low-cost with good strength composites materials have been significantly increased. In this context, the particulate wood polymer composites have attracted the researchers owing to their eco-friendliness, low-cost as they are prepared using waste wood particles, and good mechanical and physical properties. These composites

Ultrasonic testing as a non-destructive evaluation (NDE) technique is newly introduced to characterize additively manufactured composite materials to identify their anisotropic mechanical properties, being especially facile, useful and accurate approach for dimensional dependent measurement. In this study, the immersion ultrasonic technique is employed to measure the energy loss of ultrasonic elastic

Achieving production quality is a key issue faced in injection molding. Before mass production, ensuring good production quality is one of the crucial factors in injection molding. To achieve good quality, CAE technology is beneficial to assist us either to make the process window approach or to integrate with optimization strategies to improve the quality. However, there are still some questions or

Carbon/glass hybrid composite (CGHC) laminates are some of the most promising composites for lightweight applications. Sometimes these laminates are used in warm environment, such as aircraft frame structures, and this may affect their performance. In order to investigate this issue, the present research aims to study the effect of temperatures on the impact behavior and pseudo-ductile behaviour of

Surface group-rich titanium carbide nanosheets (TCNSs) were successfully fabricated by simply etching Ti3AlC2 powders and used as dielectric fillers to promote the dielectric and energy storage performances of poly (vinylidene fluoride-hexafluoropropylene) (PVDF-HFP)-based composites. The PVDF-HFP/TCNS composites realize a high dielectric constant and low dielectric loss of 16.3 and 0.034 at 102 Hz

The orientation of the dispersed phase and crystals in the injection-molded bar of an impact polypropylene copolymer (IPC) containing isotactic polypropylene (iPP), ethylene-propylene rubber (EPR) and a β-nucleating agent (β-NA) were studied simultaneously. In the IPC, iPP and EPR act as the matrix and dispersed phase, respectively. The EPR is amorphous and the iPP is crystallizable in α- and β-crystalline

Currently Polyethylene terephthalate (PET) foam is the most promising structural core materials, and the tensile mechanical properties are one of its important application indicators. Herein, environmental-friendly supercritical CO2 (ScCO2) extrusion foaming was adopted to prepare PET foam. Aiming at investigating the influence of crystals on the mechanical properties, isothermal treatment in the post-process

The mechanism analysis of the interface characteristics of sequential co-injection self-reinforced parts starts from the following three aspects. Firstly, the formation process of the bonding interface and the factors affecting the bonding strength were investigated in theory. A theoretical model of interface bonding degree, which explains the bonding degree of the interface by the penetration depth

Industrially viable processes enabling effective control of nanoparticle (NP) spatial organization in polymers are vitally important for achieving potential of nano-composites as building blocks of dynamic composites. Here, we report on the small and large strain mechanical properties of glassy polymers with spatial organization of spherical NPs controlled by the balance of the (polymer-NP)/(NP-solvent)

Properties of the surface layer of materials determine their suitability for some special applications, affecting the value of adhesion between bonding materials. In the case of dental fillings, the high value of adhesion to tooth tissue is important and determines their durability and tightness. The surface properties of dental methacrylic resin with the addition of various zeolite fillers were examined

Composites of wood waste and high-density polyethylene (HDPE) resins and different melt flow index (MFIs) was development in this work. Therefore, it was possible to assess their effect on the mechanical, thermal, and morphologic properties of these composites. The formulations were prepared using a twin-screw extruder, and the MFI, tensile strength, flexural strength, and impact strength of the composites

Natural fibers are inexpensive, biodegradable, and have similar specific properties to some synthetic fibers. Hardly any previous investigations exist of a composite made of multiple layers of pure Kevlar fiber fabric and pure Flax fiber fabric in a “sandwich structure”, but it only measured impact properties. The composite was made of 12 Flax/epoxy layers at the core in 3 possible configurations (i

Cardiovascular disease remains the leading cause of death. Damaged heart muscle is the etiology of heart failure. Heart failure is the most frequent cause of hospital and emergency room admissions. As a differentiated organ, current therapeutics and techniques can not repair or replace the damaged myocardial tissue. Myocardial tissue engineering is one of the promising treatment modalities for repairing

In this paper, polypropylene (PP) was used as raw material to prepare rectangular parts. The temperature change data of the reinforcement with different molding parameters during the filling process were collected by using the injection molding temperature visualization experimental analysis platform. The electronic universal mechanical testing machine (EMUTM) was used for mechanical testing, and the

Thermal properties of epoxy networks We present a combined experimental and theoretical investigation of thermal properties of cycloaliphatic epoxy networks. The networks are prepared from 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate ERL-4221 as a monomer and 4-methylhexahydrophthalic anhydride as a curing agent and their glass transition temperature Tg is evaluated by dynamic mechanical

In order to identify suitable flame retardant additives for the eco-friendly polymer cellulose acetate (CA), high-melting derivatives of the known flame retardant 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) were combined with the thermoplastic CA and the combustion properties were tested. CA mixtures with bis-phosphonamidates (EDA-DOPO and PIP-DOPO) showed distinct flame retardation effects

The Abrasive Jet Machining (AJM) of Polydimethylsiloxane (PDMS) is very slow or even impossible at room temperature due to its ability to absorb the energy of the impacting particles. Cryogenic Abrasive Jet Micromachining (CAJM) can enhance the material removal rate, and accordingly, the mechanical performance of PDMS can critically affect its processability. The goal of this study is to investigate

In this research article, ultrasound assisted exfoliation in a liquid phase production process has been adopted for synthesis of 2D Molybdenum Disulfide (MoS2). The energetic governing dispersion of Nano sheets in a wide range of solvents has been studied. Nano sheets dispersion in an aqueous media has been prepared with the help of high surface tension solvents like N-Methyl-1, 2-Pyyrolidone (NMP)

In order to develop an efficient and sustainable plasticizer, the waste cooking oil and malic acid were used as the main raw materials in this study to synthesize a bio-based plasticizer (acetylated-fatty acid methyl ester-malic acid ester, AC-FAME-MAE) by environment-friendly methods, and the structure was characterized by FTIR and 1H NMR. The properties of the poly (vinyl chloride) (PVC) with AC-FAME-MAE

Self-reinforced composites are polymeric materials formed by a reinforcement core and a low-melting point skin, which acts as a matrix after the consolidation step. These materials are widely exploited in industrial applications for their mechanical resistance and durability, which are themselves influenced by processing conditions and polymer composition. In the present work, two similar polypropylene-based

Laminated polymer-steel composites are promising layered materials for practical applications in the automotive industry considering their superior crush resistance capacity in terms of enhanced damping potential. In this research, the sheet lamination (SL) route of friction stir additive manufacturing (FTAM) technology was implemented for the production of a poly-methyl-methacrylate (PMMA) polymer

A series of copolyimides (CPIs) containing non-coplanar alicyclic units combined with fluorinated or rigid aromatic monomer segments is synthesized. The solid film samples display an elevated heat resistance as their degradation started at temperatures around 415 °C. Introduction into CPI backbone of bicyclic units, aromatic/aliphatic rings, angular bonds and/or low polarizable groups, determine the

This work aims to study the effect of loading magnesia (0.5–2.0 wt%) on the positron annihilation parameters and electrical properties of the PVA-PVP blend. The films were synthesized by solution casting and checked by different techniques. XRD and HRTEM of sol-gel prepared magnesia revealed that the average crystallite size was 14.29 nm with ribbon-like morphology with varying widths and lengths up

In this study, an experimental investigation is performed to observe the electromechanical response of CB (carbon black)/Acrylonitrile butadiene styrene (ABS) additive manufactured composite under quasi-static (tensile, shear, and mode-I fracture) and dynamic (mode-I fracture) loading conditions for the potential damage sensing applications. Dog bone tensile, double v-notch shear, and single edge notch

Polystyrene/graphene nanoplatelets (PS/GNP) and polystyrene/multi-walled carbon nanotube (PS/MWCNT) nanocomposites were prepared through solution mixing processing. The effect of carbon filler (CF) (GNP or MWCNT) doping on the DC/AC electrical conductivity, dielectric characteristics and optical parameters (absorption coefficient, α and band gap energy, Eg) of nanocomposites were investigated and compared

The aim of this work is to present a new approach to characterize the dielectric properties of elastomers especially at low frequencies and high electric field strength, close to the operating conditions of dielectric elastomer actuators (DEA). By means of an electro-rheological measuring cell, static (DC) and alternating (AC) high electric field strength were applied to different types of acrylonitrile-butadiene

In this investigation carbon fiber reinforced laminates with different orientation layups are prepared and studied under tensile loading condition. Multiple strain measurement techniques, namely, resistive strain gauges, embedded optical sensors and digital image correlation are used to analyze stress-strain behavior simultaneously through the thickness of composite materials, and to determine the

The aim of this work is to evaluate the dynamic properties of nonwoven flax, hemp, kenaf and glass fibre-reinforced polypropylene (PP) composites. Also, the influence of some parameters, such as the type of reinforcement, the fibre/matrix weight ratio, the fibre orientation and the porosity content, on the damping behaviour of these nonwoven composites is investigated. To this end, a free flexural

In this study, the mechanical and thermal behavior of the steel particles (SP) fabricated epoxy-based composites were investigated. The purpose of using SP was to find out their suitability and compatibility to be used as low-cost fillers for epoxy-based composites. A special steel-cast metal mold was used to fabricate the composites via self-casting method. The effect of SP concentration (10, 20,

Designing and manufacturing functional parts with enhanced mechanical property is a major goal of fused filament fabrication (FFF) for polymeric elastomers, which exhibits major advantages in producing such parts with a range of structures. But the unsatisfactory mechanical performance constrains greatly its real application and there is yet no consensus in the mechanical characterization of printed

Traditional rubber industries rely heavily on petroleum-based materials, such as carbon black (CB). The present study aims at mitigating the environmental challenges, through partial replacement of CB, while simultaneously consuming an easily accessible agricultural waste. Accordingly, cellulose nanofibre (CNF) was extracted from wheat-straw using chemo-mechanical process, which in-turn was used for

Shape memory hybrids (SMH) have drawn significant attention because they allow an easy alternative for the design of shape memory materials with tailored properties or features. In this work, a shape memory hybrid was made, based on polyvinyl alcohol (PVA) as the elastic domain and 0D silver nanoparticles (Agnps) as the transition domain, a dissolution method of mixing both components, and evaporation

In the present study, environmentally benign silver nanoparticles were synthesized using commercially purchased shrimp-shell chitosan as a capping agent. The synthesized chitosan-silver nanoparticles (Ch-AgNPs) were physico-chemically characterized by UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), high-resolution transmission electron microscopy (HR-TEM)

In this work, the growth dependence of oriented β-crystals in isotactic polypropylene (iPP) including their content, orientation and lamellar structures on the thermal treatment temperature (i.e. the final fusion temperature) is first investigated by in situ synchrotron X-ray diffraction/scattering. Interestingly, the dominance of oriented β-crystals is replaced by random α-crystals when the thermal

In post-CMP (chemical mechanical polishing) processing, the use of poly vinyl acetal (PVA) brushes to clean the wafer surface is one of the most effective and prominent techniques applied for the removal of CMP contaminants. Recently, organic contaminants induced in different types of PVA brushes during brush manufacturing have been drawing substantial research interest in CMP communities. In this