Repozytorium publikacji - Politechnika Gdańska

Nowadays, to provide a step towards circularity, the development of sustainable polymer composites should include the application of waste-based materials that can act not only as simple fillers, reducing the use of polymers but also as functional additives, limiting or eliminating the use of synthetic components. Herein, in the presented study, the main by-product of the brewing industry, brewers' spent grain (BSG), was applied as a functional filler for biocomposites based on poly(butylene adipate-co-terephthalate)/thermoplastic starch/poly(ε-caprolactone) matrix – Mater-Bi. To enhance its stabilizing functionalities and interfacial adhesion with the matrix, BSG was subjected to thermomechanical modification in a twin-screw extruder and chemical treatment with isophorone diisocyanate. Combined treatments reduced the interfacial hydrophilicity gap, facilitating melt processing, which was expressed by even a 30 % decrease in melt viscosity. Moreover, despite the incorporation of 30 wt% of low-cost BSG filler, flexural and tensile strength were hardly affected, while moduli increased even by 174 and 139 %, respectively. In situ generation of Maillard reaction products during BSG thermomechanical treatment enhanced the thermal stability of composites in an oxidative atmosphere, shifting degradation onset even by 30 °C. The stabilizing impact was also evidenced by the hindered photooxidative degradation of biocomposites. The unfavorable changes in biocomposites' surface roughness, as well as thermal properties and stability, have been limited by the increasing temperature of BSG thermomechanical treatment. Composites developed in the presented study could be effectively applied in manufacturing disposable or multi-use products, e.g., packaging materials, food containers, or cosmetic accessories like brushes, combs, or toothbrushes.

Autorzy

• dr inż. Aleksander Hejna,
• Mateusz Barczewski,
• dr inż. Paulina Kosmela link otwiera się w nowej karcie ,
• Olga Mysiukiewicz