Various Types Of Fillers Research Articles

Pultruded fibre reinforced polyurethane composites II. Effect of processing parameters on mechanical and thermal properties

This paper presents a novel process for the fabrication of pultruded polyurethane (PU) composites. The effects of the processing parameters on the mechanical properties (flexural strength and flexural modulus, etc.) and thermal properties (HDT) of the fibre reinforced PU composites by pultrusion have been studied. The processing parameters investigated include pulling rate (in-line speed), die temperature, filler type and content, and post-cure time and temperature. Results show that the composites possessed various optimum pulling rates at different die temperatures. On the basis of the DSC diagram, the swelling ratio, the mechanical properties and the thermal properties of composites, the optimum die temperature can be determined. It is found that the mechanical and thermal properties increase with filler content for various types of filler. The mechanical and thermal properties increase at a suitable post-cure temperature and time. Furthermore, the properties which decreased due to the degradation of composite materials for a long post-cure time will be discussed.

Acoustic properties of particle/polymer composites for ultrasonic transducer backing applications : IEEE Transactions on ultrasonics, ferroelectrics and frequency control, vol. 37, no. 6, pp. 506–514 (Nov. 1990)

The acoustic impedance and attenuation in composites made of particle fillers loaded in polymer matrices for transducer backing applications is investigated. The acoustic impedance of tungsten/vinyl composites was modeled, and an experimental matrix identifying variables that contribute to composite attenuation was established. The variable included the particle type, the particle size and volume fraction of a filler, the physical characteristics of the polymer matrix, and the processing route that determined the composite connectivity. Experimental results showed that with an increase in filler particle size or a decrease in volume fraction of filler, there is an increase in composite attenuation. Overall, the various types of filler, the polymer matrix, and the interface between the two contribute to attenuation in the composite, as confirmed by the acoustic properties and the microstructural analysis. >

Acoustic properties of particle/polymer composites for ultrasonic transducer backing applications

The acoustic impedance and attenuation in composites made of particle fillers loaded in polymer matrices for transducer backing applications is investigated. The acoustic impedance of tungsten/vinyl composites was modeled, and an experimental matrix identifying variables that contribute to composite attenuation was established. The variable included the particle type, the particle size and volume fraction of a filler, the physical characteristics of the polymer matrix, and the processing route that determined the composite connectivity. Experimental results showed that with an increase in filler particle size or a decrease in volume fraction of filler, there is an increase in composite attenuation. Overall, the various types of filler, the polymer matrix, and the interface between the two contribute to attenuation in the composite, as confirmed by the acoustic properties and the microstructural analysis.

Effect of filler type on the mechanical properties of latex films of natural rubber strained in liquid media

The structural mechanical properties of natural rubber with various types of fillers and different degrees of dispersion (chalk, TiO 2, polystyrene) subjected to strain in air and in the presence of an adsorption-active medium (alcohol) are studied. It is shown that in alcohol the strain mechanism depends on the nature of the filler. The structure of crazes formed in natural rubber filled with polystyrene subjected to strain in alcohol is studied. Preliminary cyclic loading can make the action of the adsorption-active medium on filled rubber less efficient.

Fillers for Fruit and Vegetable Damage Reduction

ABSTRACT TESTS of various types of fillers for fruits and vegetables were conducted and comparisons made. Those fillers designed to deliver fruits into containers with minimum velocity and drop heights are most ef-fective in minimizing impact damage; also means which spread the incoming fruit rather than concentrating it and which absorb the fruits' energy at the lowest point of release are desirable features.

Linear-expansion coefficients of glass-fiber-reinforced plastics based on polymethylsiloxane resin, up to 1000�C

The authors give the results of an investigation of the linear-expansion coefficients of glass-fiber-reinforced plastics based on polymethylsiloxane resin and various types of filler when heated to 1000°C.

The Influence of a Gas Atmosphere and Its Moisture on Sliding Wear in PTFE Compositions

PTFE materials with various types of filler are required to operate in nonlubricated piston compressors for increasingly long periods. This is not merely a matter of the material used but also of careful design calculation. In order to be able to meet certain frequently encountered requirements various filled PTFE compositions were tested in a wear lest rig and the effects of the gas and its moisture on the wear characteristics have been worked out. A different effect of the gases was sometimes stated on the wear factor of the PTFE compositions formed with different fillers so that specific application might be recognized. Finally the success is shown with results from some field compressors which were also equipped with piston rings totally pressure balanced in a new efficient method running for almost two years without ever having to replace a set of rings.