Self-Reinforced\nBiocomposites Made from Poly(3-hydroxybutyrate-<i>co</i>-3-hydroxyvalerate) (PHBV): An Innovative Approach to\nSustainable Packaging Production through Melt Processing

The production of self-reinforced composites allows for\na targeted\ntailoring of the property profile for specific applications and offers\nthe physical-mechanical advantages of a synergistic combination of\nthe two components with a high value in terms of their end-of-life\nscenarios. This study deals with the preparation and evaluation of\nself-reinforced biocomposites of poly(3-hydroxybutyrate-<i>co</i>-3-hydroxyvalerate) (PHBV) with PHBV microparticles produced for\nthe first time by industry-oriented melt processing. First, microparticles\nwith a size of 4 μm were prepared and characterized by using\nthe miniemulsion/evaporation technique. These microparticles were\nthen incorporated into the PHBV matrix by extrusion and injection\nmolding. Electron microscopy revealed particles in biocomposites.\nThe results indicate heterogeneous nucleation, leading to higher crystallinity\nat higher melting temperatures. This leads to a slight embrittlement\nand an improvement of the barrier properties against oxygen and water\nvapor. These industrially produced biocomposites benefit from particles\nby showing, among other things, higher barrier properties while retaining\ntheir green character, making them promising and easily accessible\ncandidates for future packaging applications.