Improvement of Tensile Properties of Recycled Low-Density Polyethylene by Incorporation of Calcium Carbonate Particles

Plastics are used in versatile applications includingautomobile, packaging, piping and house goods, these hugeuses attribute in the consumption of the oil reserves and theemerged waste harm the environment when it disposedirregularly. Recycling of plastics is one of the realisticsolutions to the aforementioned problems and to reduceproduction cost. However, the reduction in mechanicalproperties of recycled plastics limit their use and thusreinforced plastics become popular because of their highmechanical, physical and thermal properties. The effects ofcalcium carbonate content from 0 to 15 wt.% on the tensileproperties of recycled low-density polyethylene (RLDPE)were tested, the addition of calcium carbonate particles up to15 wt.% was found to enhance the tensile strength andmodulus of elasticity of RLDPE samples. Three calciumcarbonate particle sizes (80, 200 and 500 µm) were mixedwith RLDPE to investigate the effect of particles size on thetensile properties of RLDPE, it was found that the addition ofsmall filler particles resulted in a noticeable improvement oftensile strength and modulus of elasticity of RLDPEcompared with large filler particles. It was also observed thatthe addition of stearic acid slightly improves tensileproperties of RLDPE which may be related to improvementof the interfacial adhesion between the filler and RLDPE. Thecrystallization temperature and the degree of crystallinity ofRLDPE were increased by the addition of 7.5 wt.% calciumcarbonate particles because they act as nucleating agents.