The Role of Water Absorption on Thermal Conductivity and Mechanical Properties for (Recycling HDPE-Coal Ash) Composite

摘要

Recycling high density polyethylene (rHDPE) has great attention because of their enticing elastic properties at ambient temperature, ability of flow at elevated temperatures, and ability to be remelted for recycling use. Thus, at the present work, compound substances consisting of recycling HDPE (rHDPE) and coal ash was prepared at a different concentration (0%, 5%, 10%, 15%) of coal ash for enhancing the thermostable, rigidity, firmness, water absorption, tensile and heat conductivity qualities. SEM images and EDX analysis of rHDPE/coal ash have been studied. The water absorption (weight gain) and diffusion coefficient increase for rHDPE and rHDPE/coal ash composite with the increase time immersion in water and coal ash content, the young modulus increases with increase time immersion, and then decreased, also elasticity coefficient decreases with increase the fraction content, this lead to increase the flexibility coefficient values. A decrease in hardness values was observed after immersion, the hardness increased with an increase in coal ash content. The water entering the rHDPE/coal ash caused a change in dimensions, thus generating internal stresses and resulting in a decrease in most mechanical properties. As well as, values of thermal conductivity rises by immersion time and coal ash content. Overall, the prepared composites after increasing immersion time and fraction content indicated better properties than the composites before increasing immersion time and fraction content.