A comparative study of drinking straws made from natural resources: structural and morphological characterization

Abstract

This study focuses on identifying a high-value material using low-cost raw resources by comparing wheat straw varieties collected in Greece with other commercial straws made of reed, bamboo, paper, and bioplastic. The structural characteristics, water absorption behavior, and morphological properties of the straws were analyzed using X-ray diffraction, water immersion tests, and scanning electron microscopy. The thermal degradation was investigated using thermogravimetric analysis. The results suggest that the wheat straws exhibit a significant degree of crystallinity, with the Staramaki K1 straw exhibiting the highest crystallinity of all the straws analyzed. The mass of wheat straws increased after immersion in water, coca-cola, and fresh orange juice in contrast to the mass of bioplastic and bamboo straws, which remained constant. The surface examination revealed modifications to the strawsʼ outer and inner surfaces after immersion in the various solutions. To variable degrees, pores, cracks, peeling material, lighter patches, and anomalies were seen. The presence of a highly crystalline structure can increase the strawʼs hardness and reduce its water absorption, making it more resistant to changes brought about by the solutions. So, the Staramaki K1 wheat straw exhibits favorable properties, including high crystallinity, lower water absorption, and thermal stability, making it a promising candidate for replacing conventional plastic drinking straws.