• Silvester Bolka Polymer Technology College, Ozare 19, 2380 Slovenj Gradec, Slovenia
  • Janez Slapnik Polymer Technology College, Ozare 19, 2380 Slovenj Gradec, Slovenia
  • Rebeka Rudolf University of Maribor, Faculty of Mechanical Engineering, Smetanova 17, 2000 Maribor, Slovenia
  • Rajko Bobovnik Polymer Technology College, Ozare 19, 2380 Slovenj Gradec, Slovenia
  • Maja Mešl Polymer Technology College, Ozare 19, 2380 Slovenj Gradec, Slovenia



Biocomposites of hemp fiber reinforced bio-based high density polyethylene (green PE-HD) were prepared using a maleic anhydride grafted styrene–ethylene/butylene–styrene (SEBS-g-MA) as a compatibilizer. Several compositions of biocomposites were prepared on a tween screw extruder using the full factorial design varying two factors with two levels. The mechanical and thermal properties of test specimens, prepared by injection molding, were investigated by tensile and bending tests, DMA, and ultra-fast differential dynamic calorimetry (Flash DSC). High stiffness and strength of biocomposites in comparison to neat green PE-HD indicate very good compatibility of the constituents. Stiffness of the samples without SEBS-g-MA is slightly higher than that of the samples with SEBS-g-MA. The thermal stability of biocomposites is for all samples drastically higher as compared to neat green PE-HD. The melting (Tm) and crystallization (Tc) temperatures of the biocomposites are shifted to higher temperatures. Incorporation of SEBS-g-MA together with hemp fiber into the matrix enhances strength, stiffness, impact strength and rises thermal stability. The novel biocomposites are suitable for applications such as technical parts, which require higher stiffness and thermal stability as compared to neat green PE-HD.


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