Biocomposites based on date palm flour reinforced (70/30) polypropylene/thermoplastic starch blend: Effects of flour treatment and selective dispersion

Abstract

In this work, biocomposites have been prepared from a matrix consisting of polypropylene (PP) and thermoplastic starch (TPS) compatibilized using maleic anhydride (MA) grafted PP (PP-g-MA) and flour obtained from local date palm trees (DPF). To mediate the high hydrophilic character of the filler and attain an optimal dispersion, MA treated DPF (MA-DPF) was prepared via DPF esterification. Pretreated and MA treated DPF composites have been prepared by incorporating 10, 20 and 30% of the flour. MA-DPF has also been dispersed according to a second method consisting of dispersing the flour into starch/glycerol mixture before plasticizing to obtain MA-DPF modified TPS batches that were incorporated into PP to get the same matrix composition and flour loadings as for the first composites. The study of the composites properties proved the MA-DPF efficiency in increasing their impact resilience and diminishing their aptitude to water absorption. This was possible due to the association of the MA-DPF/TPS existing interactions to the better affinity of the esterified flour for the PP phase through its reduced hydrophilic nature. Also, SEM analysis confirmed that the interesting impact and water resistances of MA-DPF modified TPS filled PP composites derive from the DPF reinforced TPS phase consisting the materials.

Keywords:

• Thermoplastic starch
• biocomposite
• date palm flour
• interface
• surface treatment

Disclosure statement

No potential conflict of interest was reported by the authors.