Modified epoxy composites reinforced with various glass fiber contents up to 12 wt% were prepared by a simple fabrication method which involved mechanical stirring, hot pressing and post-curing. The effects of matrix modification with liquid epoxidised natural rubber (LENR) and fiber treatment with silane coupling agent on the physical, mechanical and dynamic thermal properties were examined. The modified

Instrumented indentation is a powerful in-situ mechanical characterization method and has been intensively investigated in recent years. In this work, we proposed an instrumented indentation method for soft materials based on a piezoelectric bimorph cantilever where the indentation force (F) is measured by a strain gauge and the indentation depth (h) is monitored by a piezoelectric motor driven displacement

The study of the rheological behaviour of the polymer in micro cavities is one of the aspects related to the technology of micro injection moulding (μIM) still substantially unresolved. Even today, there are no databases on the rheological characteristics of the material specific for the μIM, which, therefore, takes into account a number of important differences compared to the conventional injection

This paper deals with the analysis of polymer materials of various composition and molecular structure using Laser-Induced Breakdown Spectroscopy (LIBS). To make the discussion more transparent, we studied structurally different polymer samples using LIBS in various atmospheres (air, He, Ar) and examined their influence on signal response. We chose aliphatic (PP, PA 66, POM) and aromatic (PS, ABS)

One key issue restricting semi-crystalline polymers to be widely applied in powder bed fusion (PBF) of polymers is lack of good powder processability, especially a wide sintering window. In this work, a thermal treatment method with mixed dispersant system (TTMS) was developed to modify a common isotactic polypropylene (PP) powder to adapt for PBF. Both sintering window (SW) and particle morphology

Atomic layer deposition (ALD) on polymer substrates often requires a modification of the polymer surface properties. Plasma-enhanced ALD (PE-ALD) process is capable of establishing improved coating/substrate adhesion and layer properties by a plasma pre-treatment prior to the layer deposition. Low density polyethylene (LDPE) films were plasma treated using different gases (N2, O2, and N2+O2 mixture)

Polymer materials, such as extruded polystyrene (XPS), polyurethane (PU) and polystyrene (EPS), are extensively used as thermal insulators in cold regions to protect the engineering from frost damage. However, the performance degradation caused by freeze-thaw cycles (FTC) of polymer material has not been fully quantified. To fill this gap, a series of experiments were carried out by taking XPS board

Herein, to enhance the toughness of resins and tensile strength of fiber-reinforced polymers (FRPs), multi-wall carbon nanotubes (MWCNTs) were incorporated as a toughening material into resin matrices. The effects of the MWCNT addition on the fracture toughness (KIC) and mechanical properties of epoxy and vinyl ester resins, and the tensile strength (σr) and stiffness of impregnated basalt, carbon

A Distributed fiber Optical Sensor (DOS) was embedded inside and attached to the surface of a multi-directional continuous fiber composite laminate coupon, along with the traditional foil of Strain Gages (SG) and Digital Image Correlation (DIC), to compare the DOS measure strain response to traditional strain acquisition methods. Tensile and bending tests were performed on an Open Hole composite laminate

MDI/BD hard segment based TPUs exhibit two distinct polymorphs, form I and form II, when it is solution-cast at 60 and 145 °C. Form I shows paracrystalline features, whereas form II typically shows semi-crystalline spherulitic structures with birefringence. The melting behavior of these two forms is investigated using in-situ FTIR and simultaneous in-situ SAXS and WAXS techniques. The long spacing

A systematic experimental investigation of the coupling between the extensional flow and the crystallization of a commercial grade polypropylene is presented. A modified Sentmanat extensional device allows one to generate a uniaxial extensional flow in the absence of gravity sagging and monitoring its effect on the kinetics of crystallization via in-situ visualization of the sample in polarised light

The limited quantity of modeling papers on halloysite nanotubes (HNT)-reinforced nanocomposites restricts the optimization of properties for multifunctional applications. In this paper, we develop a two-step technique to approximate the tensile strength for this category of materials. At the first stage, HNT and surrounding interphase are assumed as pseudoparticles and their strength is estimated by

The presence of a polyethylene (PE) fraction in recycled polypropylene (PP) will influence the processing as well as mechanical and thermal properties of recycled polypropylene. The objective of this work has been to compare methods used to determine the fraction of PE in recycled PP, establishing calibration curves for each method. Plastics waste will be a mix of different grades – homopolymers and

Enhancement interaction between polybutadiene (PB) nanoparticle and polypropylene (PP) matrix by grafts via hydrogen bonding was verified and characterized by dynamic rheological analysis. The introduction of acrylamide (AM) facilitated PB uniform distribution in PP and strengthened interfacial interaction. The correlated structure based on H-bonding interaction leading to the viscoelastic nonlinearity

Development of suitable catalyst binder with reasonable proton conductivity is of great importance for improving catalytic performance of oxygen reduction reactions of platinum-based catalysts. Herein, we report that polybenzimidazole grafted with protic ionic liquid moieties is an effective catalyst binder for oxygen reduction of Pt/C catalysts. The designed Pt/C catalyst layer using protic ionic

Thanks to the unique flexural properties, sandwich composites are considered as irreplaceable structures in many industrial fields, but their susceptibility to impact events is still a considerable drawback that undermines their structural integrity determining a reduction of their load-bearing capabilities. Considering that the core material plays the major role to distance the skins, the knowledge

Machinery subject to internal and/or external mechanical excitations typically require careful control or avoidance of undesirable vibration behavior to meet operational constraints. To address this difficulty, the design, fabrication and testing of multi-polymer axially graded (segmented) structures fabricated through 3D printing was performed. Experiments were conducted on axially graded beams composed

At present, the simulation cannot satisfactorily reproduce the actual vibration behavior of short-fiber reinforced plastics. This is because the required linear-viscoelastic material properties, in particular damping, are often not useable in the desired frequency range of up to 10 kHz. For this purpose, a newly reconsidered test method as an alternative to the established dynamic mechanical analysis

Herein, epoxy resins for composite liquid oxygen (LOX) fuel tanks are modified with phosphorous flame retardant (DOPO) and brominated epoxy resin (EX48). With the incorporation of DOPO and EX48, the processing properties requirements for the hot-melt prepreg are contented with the significantly enhanced viscosity of the modified epoxy resin. At the same time, the tensile performance, flexural performance

In the present work single-lap-joint specimens with an adhesive layer of micron-scale thickness were prepared, and the effects of adhesive thickness and surface treatments (Milling, SAA, PAA, and SB + SAA) on the bond strength were investigated by tensile tests and surface analyses. The shear strength increases with the increase of adhesive thickness for the milling surface, while it is not presented

Composite films of Polyvinyl alcohol (PVA) and hybrid materials based on salicylic acid –layered zinc hydroxide acetate (ZHA-SA) using zinc hydroxide acetate (ZHA) as host matrix were obtained by the casting method. The resulting composite films were characterized by FT-IR, X-ray diffraction, scanning electron microscopy (SEM) and atomic force microscopy (AFM) evidencing the incorporation of the layered

This study investigates the tensile and compressive failure behavior of a single-lap joint of green composites obtained by resistance welding. The green composites composed of poly (lactic)acid (PLA) and bamboo fiber were fabricated in a hot compression by the film-stacking method. The different heating elements namely polypyrrole (conductive polymer), carbon fiber (CF) fabric, and stainless steel

Stubble resistance of tread rubber vulcanizate of a tyre is crucial, especially for the off-the road (OTR) tyres. However, it has not been vividly discussed in the literature. Here, we developed a test method for stubble resistance, and studied the effect of short aramid fibre and two different types of resins on the stubble resistance of a conventional tire tread recipe with a view to its improvement

Zinc oxide particles in needle shape were synthesized by hydrothermal route varying the reactor rotation speed (600, 1200, and 1800 rpm). The synthesized particles and commercial nanosized ZnO were characterized through X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and scanning electronic microscopy (SEM), aiming to evaluate the influence

High density polyethylene (HDPE) is a material which was known for its biocompatibility and its application for artificial joints. However, the wear resistance of a HDPE can be enhanced with addition of reinforcements. Molybdenum disulfide (MoS2), cuttlebone (CB) and red coral (RC) are auspicious reinforcements of HDPE. The wear resistance of the elaborated composite materials in physiological environment

To investigate the anti-impact behavior and loading rate sensitivity of bamboo fiber reinforced composite (BFRC) beams, low-velocity-impact flexural experiments were performed under impact velocity changing from 2 m/s to 10 m/s. Quasi-static flexural tests were carried out under the same conditions to supply a quasi-static reference to the dynamic performance. Velocity-dependent effects of the impact

Tire rolling deformation consists of valuable information for vehicle control and tire development applications. To gain insight into this deformation, both model-based and tire sensor-based approaches have been investigated in previous studies. However, existing tire models oversimplified the pressure distribution in the tire-road contact due to a lack of related experiment data especially for deformations

Recent advances focused on smart polymers have demonstrated the numerous advantages regarding other structures because they can adapt the behavior depending on physicochemical properties. In this way, functionalized thermoresponsive polymers with organometallic complexes were profoundly analyzed. Consequently, novel catalytic systems or biomedical devices could be developed. This publication focuses

This paper aims to investigate the relationship between local moisture concentration and mesoscale mechanical properties of epoxy adhesive under elevated temperature. Araldite® 2015 was chosen as the target adhesive due to its curing stability and possible validation with previously published literatures. The specimens were aged at 60 oC in deionised water and 5%wt NaCl solution, separately, with the

Superabsorbent polymers (SAPs) have been widely used and are attracting increasing attention in agricultural field because they dramatically enhance water use efficiency. In this review, representative achievements in the design and modification of SAPs with specific functions are highlighted, as well as their applications in agriculture. Two key properties of SAPs, water absorption and retention behaviors

A novel polyethersulfone (PES) nanocomposite membrane incorporated with lanthanum vanadate (LaVO3) nanosheets was fabricated based on phase inversion approach. The morphology and the performance of the fabricated nanocomposite membranes were systematically studied by ATR-FTIR, SEM, AFM, porosity, water contact angle, antifouling and rejection measurements. The resulting membranes showed an asymmetric

The purpose of this paper is to achieve efficient detection and prediction of delamination failure of stretchable interconnects by using digital image correlation (DIC) methods. In order to achieve this goal, a visual experiment system and a delamination failure detection and prediction method are designed, and the mechanical characteristics of two-dimensional horseshoe-shaped interconnect are experimentally

Rubber dams employed for endodontic treatment are commonly based on natural rubber latex compounds and it is essential that they remain unbroken throughout the different procedures. The in-use failure of some types of rubber dams can be related to the time spent under tension in contact with saliva and/or to sodium hypochlorite. Five different types of commercial rubber dams were assessed with respect

In this study, composite membranes based on polyphenylene oxide, polyaniline (as separation layer) and interpenetrating layer of polyphenylene oxide and polyaniline were prepared. It was demonstrated for the first time that the interpenetrating layer of polyphenylene oxide and polyaniline plays a crucial role in the transport and separation properties. Moreover, the preparation of such composite membranes

Near infrared to ultraviolet (NIR-to-UV) up-conversion nanocomposites, composed of an upconversion nanoparticle (UCNP) core and a transformable polyspiropyran shell, were prepared by distillation precipitation polymerization and the template method. The polyspiropyran shell can undergo reversible hydrophoblic-hydrophilic transformations through the switching of UV and visible light and by variation

Most traditional pesticide formulations contain environmentally unfriendly components and suffer from low utilization efficiency due to the loss, decomposition and burst release of active ingredients. Encapsulating pesticides using nanocarriers is a feasible approach to overcome these defects. In this work, the emamectin benzoate-loaded zein nanoparticles were fabricated by an antisolvent precipitation

A linear diamides derivative-containing organic compound (TMC306) as a nucleator was incorporated into biodegradable poly (ethylene succinate) (PES) to investigate effect of TMC306 on crystallization behavior and aggregated structure of PES. Upon incorporation of TMC306 with lower weight fraction (fTMC306), crystallization temperature (Tc), crystallization rate (k) and degree of crystallinity (Xc)

Physically cross-linked high strength hydrogel which can be completely degradable was prepared by the micellar copolymerization using acrylic acid (AA) and octadecyl acrylate as the hydrophobic monomer. The hydrogel was characterized by the infrared absorption spectrum. The tensile strengths of hydrogels were tested in various raw materials, surfactant and initiator ratios. The degradation performances

Fracture toughness (FT) and Tensile strength (TS) of epoxy reinforced amine-functionalized MWCNTs (A-MWCNTs)/graphene nanoparticles (GNPs) composites are investigated in cryogenic environment. Simplex centroid design is employed to decide the composition of samples. FT and TS of epoxy improved significantly on incorporating 0.25 wt% of either A-MWCNTs or GNPs, but increasing the content of nanofillers

In this paper, we study the optimal photoinitiator (camphorquinone, CQ) concentration for light-cured dental resins by combining such properties as the degree of conversion, mechanical properties, and curing depth (the depth at which the hardness is 80% of the surface hardness). The material properties of the light-cured dental resins (Bis-GMA/TEGDMA in a mass ratio of 70:30) are characterized by in-situ

Creep behavior of high-density polyethylene (HDPE) was investigated. HDPE has many engineering applications in different industries such as piping systems, cable and wiring, automotive parts, storage containers, and biomedical implants. The temperatures chosen were 23, 53, and 82 °C based on the service temperature range for application in design of automotive fuel tanks. Creep strength decreased and

The in-situ quantitative characterization of the interface structure and properties of carbon fiber/epoxy resin composites was carried out by using peak force quantitative nanomechanical mapping (PF-QNM) technology in this study. The mechanism of hygrothermal damage was developed. It is found that the hygrothermal aging can be divided into three stages. In the first stage, the resin matrix and the

Polyurethane elastomer is investigated by atomic force microscopy (AFM) in a regime of fast nanoindentation (simultaneous getting relief and mechanical properties of the surface). The hard phase of the polymer has a fibrillar structure and inhomogeneously distributed in the softer matrix. The surface is covered by a nanolayer of the soft phase and the obtained relief depends on the depth of indentation:

High isotactic polybutene-1 (HiPB) plays important roles in presenting outstanding resistance to creep and crack at high temperature. Therefore, rapid and accurate measurement of the HiPB is extremely important for both synthesis and application of polybutene-1 (PB). In this work, solvent extraction fractionation with diethyl ether (DE) and n-hexane (C6) as solvents (DE-C6 method) and an improved fractionation

The relation of molecular structures, morphologies, and thermoelectric (TE) properties of the poly(3,4-ethylenedioxythiophene): poly (styrene sulfonate)/polyaniline (PEDOT: PSS/PANi) composite films have been carefully investigated. Various nanostructured PANi were synthesized firstly. Then PEDOT: PSS were employed to prepare PEDOT: PSS/PANi composite films. The morphological and structural characterization

The present study demonstrated a new fast colorimetric humidity sensor using the opal hydrogel composite (OHC). First, a highly monodisperse polystyrene (PS) latex was synthesized by soap-free emulsion polymerization and deposited on a glass substrate in order to form a three-dimensional opal photonic crystal. Then, the homogenous hydrogel precursor was infiltrated into the interstitial space of opal

Three techniques for determining the hydrogen permeation properties of rubber samples were developed based on the volumetric and gravimetric measurements of released H2 gas after sample decompression. These methods include gas chromatography (GC) by thermal desorption analysis (TDA), volumetric collection (VC) measurement of hydrogen by graduated cylinder and gravimetric (GM) measurement by electronic

In this paper, silver (Ag) nanoparticles were synthesized by utilizing an aqueous extract of fresh leaves of Chenopodium murale which is considered a cost-effective and eco-friendly approach. The sol-gel technique was used to syntheses TiO2 nanoparticles and different methods were used to characterize the nanoparticles (Ag and TiO2) including UV–Vis spectroscopy, XRD, and TEM. Also, new nanocomposites