عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Nowadays, polymer blends usages increase more and more in order to produce materials with better properties. According to many research works, the blends of polyolefins have shown industrial importance. The purpose of this project was to carry out some investigations on fibers melt spun from the polypropylene and low density polyethylene blends. PP and LDPE are immiscible. PP/LDPE blend filament yarns with the blend ratios of 100/0, 99/1, 97/3, 95/5, 93/7, 90/10 were produced by the melt spinning process. Microstructure (density, DSC, birefringence) and physical properties (tenacity, breaking elongation, initial modulus and shrinkage of samples) were measured and compared. The results showed that presence of LDPE in blend samples does not influence the density and crystallinity of PP. However, increasing the fraction of LDPE in blend samples also increases the shrinkage of drawn yarns. The tenacity of as-spun and drawn yarns displayed a downward trend by increasing the LDPE in blend. But the breaking elongation presented an upward trend. Tensile properties of textured yarns spun from PP/LDPE blends were higher than those of pure PP at all applied texturing temperatures (apart from 150C). Increasing the texturing temperature resulted in the increasing of crimp properties. However, the rate of increase is lower when the fraction of LDPE is higher.