Micromechanical studies on binary and ternary blends of polyethylene, polypropylene, and polyamide 66: Influence of the compatibilizer

• Published in: International journal of polymeric materials Vol. 52; no. 10; pp. 939 - 956
• Main Authors: Krache, R., Benachour, D., Cagiao, M. E., Calleja, F. J. Baltá, Bayer, R. K., Tschöpe, F.
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 2003; Taylor & Francis
• Subjects: Applied sciences; Binary And Ternary Blends; Blend Composition; Compatibilizer; Crystallinity; Exact sciences and technology; Mechanical properties; Microhardness; Organic polymers; Physicochemistry of polymers; Polyamide; Polyethylene; Polypropylene; Processing Conditions; Properties and characterization; Tensile Properties; Polyethylene; Polymer blends; SEBS; Ternary mixture; Propylene polymer; Mechanical properties; Tensile property; polyamide; polypropylene; Crystallinity; blend composition; Experimental study; Fabrication property relation; Compatibilizer; Microhardness; Heterogeneous mixture; binary and ternary blends; Binary mixture; tensile properties; Amide 66 polymer; processing conditions; Fabrication structure relation
• ISSN: 0091-4037; 1563-535X
• DOI: 10.1080/713743640

The microhardness H of PE/PP/PA blends prepared by one-Step and two-step mixing processes was determined. The microhardness of the blends was markedly affected by the composition. Results reveal that the presence of compatibilizers induces a remarkable decrease in the H of the blends. It is shown that the large deviation of H from the additivity law of the single components is mainly due to the depression of the crystal hardness values of polymer crystals. However, the decrease in crystallinity of the individual components in each blend also has to be considered. Comparison of experimental and calculated H data and analysis of DSC results in all the blends suggest that the surface free energy of the crystals increases as a consequence of the blending process. Results are discussed in light ofthe changes occurring in the defective boundary surface of the crystals. Finally, a linear relationship between the hardness H and the yield stress σ y , as well as between H and the Young's modulus E, are found. The deviation of the H/ σ y and the H/E ratios from the theoretical predictions are discussed in the light of the strain rate used and the compatibilizer effects on the blend structural properties.