Long-Term Creep Compliance of Wood Polymer Composites: Using Untreated Wood Fibers as a Filler in Recycled and Neat Polypropylene Matrix

Marko Bek; Alexandra Aulova; Klementina Pušnik Črešnar; Sebastjan Matkovič; Mitjan Kalin; Lidija Slemenik Perše

doi:10.3390/polym14132539

Long-Term Creep Compliance of Wood Polymer Composites: Using Untreated Wood Fibers as a Filler in Recycled and Neat Polypropylene Matrix

Polymers (Basel). 2022 Jun 22;14(13):2539. doi: 10.3390/polym14132539.

Authors

Marko Bek¹, Alexandra Aulova², Klementina Pušnik Črešnar³, Sebastjan Matkovič¹, Mitjan Kalin¹, Lidija Slemenik Perše¹

Affiliations

¹ Faculty of Mechanical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia.
² Department of Materials and Manufacturing Technology, Chalmers University of Technology, 41296 Gothenburg, Sweden.
³ Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia.

Abstract

Neat (NPP) and recycled (RPP) polypropylene matrix materials were used to prepare wood-polymer composites with untreated wood fibers up to 40 wt.%. Long-term creep properties obtained through the time-temperature superposition showed superior creep resistance of composites with NPP matrix. In part, this is attributed to their higher crystallinity and better interfacial adhesion caused by the formation of a transcrystalline layer. This difference resulted in up to 25% creep compliance reduction of composites with NPP matrix compared to composites with recycled (RPP) polypropylene matrix, which does not form a transcrystalline layer between the fibers and polymer matrix. Despite the overall inferior creep performance of composites with RPP matrix, from the 20 wt.% on, the creep compliance is comparable and even surpasses the creep performance of unfilled NPP matrix and can be a promising way to promote sustainability.

Keywords: creep; durability; recycling; wood; wood–polymer composites.

Abstract

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