Work

Mechanical and Anti-Icing Properties of Polyurethane/Carbon Fiber-Reinforced Polymer Composites with Carbonized Coffee Grounds

Year: 2025

Type: article

Abstract: Spent coffee grounds represent an abundant waste resource with potential for sustainable material applications. This study investigates the use of carbonized spent coffee grounds (CSCG) as fillers in polyurethane (PU) coatings for carbon fiber-reinforced polymer (CFRP) substrates to enhance mechanical durability and anti-icing performance. SCGs were dried, sieved (<100 µm), and oxidatively carbonized in air at 100–300 °C for 60–120 min, then incorporated into PU at 1 or 5 wt.% and applied by spray-coating. A full-factorial design was employed to evaluate the effects of carbonization temperature, particle size, and filler loading. The optimized formulation (300 °C, 100 µm, 5 wt.%) showed the highest water contact angle (103.5°), lowest work of adhesion (55.8 mJ/m2), and improved thermal stability with 60% char yield. Mechanical testing revealed increased tensile modulus with reduced strain, and differential scanning calorimetry indicated an upward shift in glass-transition temperature, suggesting restricted chain mobility. Ice formation at 0 °C was sparse and discontinuous, attributed to lowered polar surface energy, rough surface texture, and porous carbon morphology. These results demonstrate that CSCGs are effective sustainable fillers for PU coatings, offering combined improvements in mechanical, thermal, and anti-icing properties suitable for aerospace, wind power, and other icing-prone applications.

Source: Materials

DOI: 10.3390/ma18194533

Authors: Seong Baek Yang, Min Ji Woo, Donghyeon Lee, Jong-Hyun Kim, Sang Yong Nam, Dong-Jun Kwon

Institution: Gyeongsang National University

Language: English

Topic: Polymer Science and Applications

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Climate action

Open Access status: gold

Estimated APC paid: $3,137