Study the Effect of Absorption Solution for Same Composite Polymeric Material
In this paper concerns an investigation of absorption solution in materials of polymeric composite were prepared two types of the matrix material were used (PE,PVC). Also two types of fiber were used (woven and short glass fiber ).with volume fraction 20%. The sample were immersed in different solution (NaCO3-KOH –HCL , Normality 0.5 N) for equal time at constant temperature (room temperature ±20C ) . The result show that the relative mass gain increased with increasing the immersion time till they tend saturation moisture mass after that the relative mass gain decreased . The result show that sample in (KOH)solution had higher mass gain while the sample immersed in (HCL) had lower mass gain .Also the results show that the sample immersed in (NaCO3) has maximum diffusion coefficient which means minimum absorption resistance, while the sample immersed in (HCL) has minimum diffusion coefficient which means maximum absorption resistance.
Analysis of filler-fibre interaction in fly ash filled short fibre-epoxy composites using ultrasonic NDE
Size and aspect ratio are believed to influence the rheology or the flow in the mixture and in turn the mechanical performance of the composites. Fillers and fibres when used in combination are expected to complement each other’s performance resulting in better properties for the composite. They also reduce the extent of matrix polymer required in the system. Composites involving fillers and fibres individually and in combination are studied for the level of defect population using NDE and the mechanical performance under compression correlated with such an analysis. It was found that inclusion filler-fibre combination besides yielding better physical properties like density also yielded improved mechanical properties like strength and modulus. These properties showed an improvement of about 30–40% as compared to the ones where a single reinforcement either ash or fibre was used. Further, they exhibited uniform distribution of defects whose population was least compared to the situation where only one component (either filler or fibre) as reinforcement was tried.
Processing of short fibre/thermosetting matrix composites☆
The fundamental aspects of the processing of thermosetting matrix composites with short fibres in compression moulding technologies are presented. The reaction kinetics and the rheology of compounds based on unsaturated polyester matrices have been characterized as a function of different processing variables (temperature and shear rate). The effects of the filler (calcium carbonate) and the reinforcement (glass fibres) on the curing kinetics of unsaturated polyester resins were studied by differential scanning calorimetry (d.s.c.), and the rheological properties of the compounds were analysed using parallel-plate rheometry. The results of the d.s.c. characterization were used to develop an empirical kinetic model accounting for diffusion control effects, while d.s.c. and rheological measurements were combined to obtain correlations between viscosity, extent of reaction, temperature and shear rate. The complete chemorheological model was verified through rheological tests performed at different heating rates and angular frequencies. The model developed in this work has been integrated into a general processing model for the description of the moulding behaviour of thermosetting matrix compounds for automotive applications. Excellent agreement between model predictions and experimental results has been obtained.