Bioactive Propolis-Silane System as Antifungal Agent in Lignocellulosic-Polymer Composites

Area of Science:

• Materials Science
• Polymer Science
• Biotechnology

Background:

• Polymer composites with lignocellulosic fillers offer sustainability benefits but suffer from biodegradation, limiting their use in external applications.
• Fungal attack and UV radiation degrade these materials, compromising their structural integrity and aesthetic appeal.
• Effective modification strategies are needed to improve the durability and performance of wood-plastic composites.

Purpose of the Study:

• To develop and evaluate an innovative hybrid propolis-silane modifier for enhancing the resistance of polypropylene-wood composites to fungal attack and UV radiation.
• To assess the impact of this modification on the interfacial adhesion between the lignocellulosic filler and the polymer matrix.
• To investigate the combined effects of fungal exposure and UV radiation on the modified and unmodified composites.

Main Methods:

• Polypropylene composites containing 30% pine wood were fabricated using extrusion and pressing.
• Samples were subjected to fungal exposure (Coriolus versicolor, Coniophora puteana, Chaetomium globosum) for 8 weeks.
• Advanced characterization techniques including X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) were employed, alongside mycological studies and mechanical testing.

Main Results:

• The propolis-silane modification significantly increased resistance to fungal degradation, with minimal changes in the supermolecular structure and spectral bands of the composites.
• Unmodified composites showed significant structural changes indicative of decay after fungal exposure.
• Modified composites exhibited inhibited photo- and biodegradation, with only slight deterioration in strength parameters after combined UV and fungal exposure.

Conclusions:

• The hybrid propolis-silane modifier effectively enhances the antifungal and UV-stabilizing properties of wood-plastic composites.
• This innovative treatment improves the durability and performance of composites, making them suitable for demanding external applications.
• The modifier acts as an eco-friendly agent, promoting the longevity of renewable material-based composites.