Preparation and Assessment of Phase Morphology, Rheological Properties, and Thermal Behavior of Low-Density Polyethylene/Polyhexene-1 Blends

In this work, polyhexene-1 (PH-1) is synthesized by polymerization of hexane-1 with Ziegler-Natta catalyst and melt blended with low-density polyethylene (LDPE). The phase morphology, rheology, crystallization, and thermal behavior of (LDPE)/PH-1 blends are investigated. A good compatibility is observed in the blends up to 10wt% PH-1 and the most of the droplets in the fractured surface are covered with and buried in the LDPE matrix and at higher percentage the droplet particle size significantly increased. The effect of microstructure of the blends on the flow behavior is studied by small amplitude oscillation rheology. By decreasing the compatibility and increasing the particle size, the Cole-Cole plots are deviated from the semi-circular shape at higher percentages than 10wt% of PH-1. The change in the crystallization and melting behavior of LDPE in the blends are studied by differential scanning calorimetry and X-ray diffraction (XRD). It is found that by increasing the PH-1 the melting temperature of LDPE decreased from 112.5 to 110.8 degrees C and crystallization temperature increased from 95.2 to 97.7 degrees C which is evident of the nucleation effect. The intensity of (110) peak in XRD test declined as a remake of amorphous part of LDPE and the degree of crystallinity of LDPE decreased from 28 to 22% at 20wt% PH-1. [GRAPHICS] .