The effect of fines on the consolidation of Eucalyptus/PLA fiber air-laid sheets

Bio-based nonwoven products are potentially more sustainable with a lower environmental impact than the current generation of petrochemical nonwovens. This work aims to examine the structure and performance of an air-laid sheet composed of defibrated Eucalyptus pulp and polylactic acid (PLA) fibers. In this work, Eucalyptus pulp dry fibers were prepared through two different methodologies, yielding fibers with distinct morphological properties. In an air-laid former, specially conceived for this work, sheets with a grammage of 100 g m(-2) were prepared from fiber blends with moisture to aid in the consolidation. The resulting air-laid sheets were characterized by their structural, mechanical, and water sorption properties. The results showed that Eucalyptus fibers with fewer fines and fiber deformations yielded more absorbent sheets. The high fines group gave higher sheet strength. 30% of PLA fiber gave the best combination of strength and absorption capacity and stretch at break. The improvement in bulk, dry and wet strength was possible for air-laid sheets produced from the Eucalyptus/PLA mixture. The results showed that PLA has a strong interaction with the sheet fines, affecting consolidation and performance of the final product.

Automated summary

This study aims to investigate the structure and performance of an air-laid sheet made of defibrated Eucalyptus pulp and polylactic acid (PLA) fibers. Different methodologies were used to prepare Eucalyptus pulp dry fibers, resulting in fibers with distinct morphological properties. Sheets with a grammage of 100 g m(-2) were prepared using a specially designed air-laid former, and their structural, mechanical, and water sorption properties were characterized. The results showed that sheets made from Eucalyptus fibers with fewer fines and fiber deformations had better absorbency, while those with more fines had higher strength. Sheets with 30% PLA fiber content exhibited the best combination of strength, absorption capacity, and stretch at break. The presence of PLA had a strong interaction with the fines in the sheet, affecting its consolidation and performance.