Preparation and properties of reactive melt compounded bimodal polyethylene for usage in steel pipe coating

Multi modal polyethylene grades have high mechanical properties and high long time properties like high ESCR and good processability. These properties are result of broad molecular weight distribution. Multi modal polyethylene mostly is produced by synthetic methods but in this work, melt blending of polyethylene grades are used to approaching a multi modal polyethylene. Four grades of polyethylene are used. The base polyethylene is a medium density polyethylene (density 0.938 g/cm3 and MFI 4.0 g/10 min), the others have low MFI (0.05, 0.05 and 0.1 g/10min) that used at different percentage and variation of mechanical properties is investigated. Because of sharp difference in viscosities, compounds do not have good compatibility. To increase compatibility and improve some of mechanical properties (such as tensile and elongation at break), reactive compatibilization by peroxides such as Decumyl peroxide and tert-butyl peroxybenzoate and others were tested. It shows that reactive compatibilization increases average molecular weight and molecular weight distribution that it will improve mechanical properties of blends

کلیدواژه ها:

multi modal polyethylene ، reactive blending ، peroxide