the aim of this study was to assess the effect of bleaching on elution of monomers from nanofilled and microhybrid composites.80 samples (5mm diameter and 3mm thickness) of each composite were prepared. after curing, half of them were randomly polished. each group was divided into 8 subgroups and immersed in water or 10%, 20% and 30% h2o2 for 3 or 8 hours. eluted bis-gma (bis-phenol a glycidyl ...

Natural fiber as reinforcement filler in polymer composites is an attractive approach due to being fully biodegradable and cheap. However, incompatibility between hydrophilic natural fiber and hydrophobic polymer matrix restricts the application. The current studies focus on the effects of incorporation of silane treated OPMF into polylactic acid (PLA)/polycaprolactone (PCL)/nanoclay/OPMF hybri...

Activated carbon fiber/carbon aerogel (ACF/CA) composites were fabricated by gelling a mixture of ACF and resorcinol and furfural, followed by supercritical drying of the mixture in isopropanol. The product then went through carbonization in a nitrogen atmosphere. The fabrication conditions, such as the mass content of R–F, the content of the ACF added, and the gelation temperature, were explor...

Ceramic matrix composites (CMC’s), particularly silicon carbide (SiC) fiber-reinforced SiC-matrix (SiC/SiC) composites, have been studied for advanced nuclear energy applications for more than a decade. The perceived potentials for advanced SiC/SiC composites include the ability to operate at temperature regimes much higher than heat-resistant alloys, the inherent low inducedactivation nuclear ...

Polypropylene/wood flour composites were melting compounded in an internal mixer at 190°C and 60 rpm rotor speed and then samples were fabricated by injection molding. Effects wood flour content on the physical properties of composites was investigated. For this purpose, hardness, water absorption and thickness swelling of samples was determined at different levels of wood flour content. The re...

The influence of fiberlmatrix interactions on the mechanical behavior of ceramic matrix composites is examined on glass matrix composites and mainly on composites made by chemical vapor infiltration (CVI) of a fiber preform by a SiC matrix. Then the relationships between interfaces and features of the stress-strain behavior are highlighted on microcomposite specimens using experimental data and...

statement of problem: the degree of conversion depends on the material composition, light source properties, distance from light source, light intensity, curing time, and other factors such as shade and translucency. objectives: in the present study, we evaluated the effects of different light- curing modes and shades of methacrylate and silorane-based resin composites on the degree of conversi...

This paper presents an experimental study on the static and dynamic mechanical properties of nonwoven based flax fibre reinforced polypropylene composites. The effect of zein modification on flax fibres is also reported. Flax nonwovens were treated with zein coupling agent, which is a protein extracted from corn. Composites were prepared using nonwovens treated with zein solution. The tensile, ...

The use of natural fiber reinforced composites has continuously increased during recent years due to their low density, low cost and environmental friendliness. At current study, a preliminary investigation on the impact properties and morphologies of unsaturated polyester reinforced by jute woven fabric from the used coffee bags with different moisture contents were carried out. Additionally, ...

Fly ash, which consists of hollow particles with porous shells, was introduced into polyurea elastomer. A one-step method was chosen to fabricate pure polyurea and the polyurea matrix for the composites based on Isonate® 2143L (diisocyanate) and Versalink® P-1000 (diamine). Scanning electron microscopy was used to observe the fracture surfaces of the composites. Particle size and volume fractio...