Influence of technological processing parameters on the properties of carbon filled thermoplastics

Abstract

The effect of processing parameters of injection molding on the mechanical and tribotechnical properties of carbon plastics based on polyacetals is investigated. The copolymer of 1,3,5-trioxane with 1,3- Thermoplastic carbon fiber-reinforced plastics (CFRPs) are increasingly being used in mechanical, radio, and instrument engineering since they have high physicomechanical properties, low friction coefficient, and can be easily processed into products. To manufacture parts of plain bearings for the friction joints of machines and mechanisms, randomly reinforced CFRPs based on polyamides are often used [1]. However, these composites cannot be utilized when producing parts that will be operated in humid environment. CFRP based on copolymers of formaldehyde have high resistance to moisture and chemical reagents, low friction coefficient and wear intensity, and relatively low processing temperature, and their mechanical properties do not degrade up to a temperature of 120"C. The mechanical properties of products made of CFRP based on copolymers of formaldehyde (polyacetals) are~considerably affected by the technological parameters of processing by . injection molding. The effect of these parameters on the properties of unfilled copolymers of formaldehyde has been described earlier [2]. The aim of the present study is to examine this effect for CFRP based on copolyrners of formaldehyde.As the thermoplastic matrix, the copolymer of 1,3,5-trioxane with 1,3-dioxolane (CTD) was utilized. As a reinforcing filler, we used medium-modulus hydrated cellulose Ural LO-24 carbon fibers (filling degree 20 wt.% ). The polymer was mixed with the carbon fibers in an ED-2,2 screw-disk extruder. Standard test specimens were obtained by injection molding. The physicomechanical properties of the CFRP were determined

High-temperature resistance and wave-transmitting quartz-fibre/polyimide composite

“…The flexural strength reaches its maximum at a temperature of 380°C and then starts to decrease. The decrease in the mechanical properties of composites can be explained by the fact that the composite is kept at a higher temperature for a long period of time, which leads to the destruction of the polymer matrix and to degradation of the mechanical properties of composite [20].…”

Simultaneous optimization of the mechanical properties of postconsumer natural fiber/plastic composites: Processing analysis

“…Although the authors produced their composites in two steps (compounding or mixing followed by molding), they reported or investigated independently the influence of each manufacturing step parameters: compounding 4-7,10-14 or molding. [7][8][9]12,[15][16][17] Simultaneous analysis of both steps is seldom presented, but this information would enable a better understanding of the complete manufacturing process from beginning to the end; i.e. influence of interactions between the parameters of both processing steps.…”