Processing and mechanical performances of Poly(Butylene Succinate-co-Adipate) (PBSA) and raw hydrolyzed collagen (HC) thermoplastic blends

In this study, blends of poly (butylene succinate-co-adipate) (PBSA) and raw hydrolyzed collagen (HC), a byproduct of the tannery industry, were investigated in terms of processing by blown film extrusion/injection molding and thermal/rheological/mechanical properties. PBSA/HC blends were prepared by melting extrusion with HC contents in the range 5-20 wt%. The blown films, produced up to 10 wt% of HC, resulted flexible with satisfactory tensile properties and excellent tear resistance. While, the blends with higher HC contents, up 20 wt %, resulted suitable for the injection molding obtaining molded specimens with good tensile properties (with addition of 5 wt% of HC a maximum value of elongation at break of 1200%). Scanning electron microscopy (SEM) revealed that the HC was uniformly dispersed into the continuous phase PBSA up to 10 wt%, while at higher contents phase separation occurred without compromising their processing by injection molding. The results obtained encourage the use of HC in PBSA-based blends to produce compostable/biodegradable films or molded products for applications in agriculture due also to the fertilizing properties of HC.