Effect of Particle Size of Calcium Carbonate on the Short-Term Tensile Creep Properties of Polypropylene Block Copolymer (PPB)

Polypropylene block copolymer (PPB) composite materials consist of polypropylene and micro particle mineral filled materials that is calcium carbonate (CC). The samples to be used in the tests were formed by adding calcium carbonate (CC) mineral in three different particle sizes. The different commercial CC minerals average particle sizes are 1.65 μm, 2.15 μm, 5 μm. The PPB composite materials are prepared at constant quantities of CC with content of 17.5 percentage of the volume ratio (or 38.89% in weight). In this study, the short time tensile creep behavior of 17,5 vol. % different particle sizes CC filled PPB materials were investigated for different stress levels. Stress levels were selected from the stress below its yield strength. The stress levels are at 8 MPa, 16 MPa. As a result, it was found that the creep elongation or strain drop (∆e) values decrease in the CC filled PPB materials according to the unfilled PPB material. In addition, it has been found that the absorbed energy levels reduce as the particle size increases.