Poly(lactic acid) (PLA) is considered the best candidate biobased material alternative to petroleum-based polyethylene terephthalate due to its renewability and biodegradability. However, the crucial dyeing issue of PLA filament limits its applications in the textile industry. Herein, a green deep eutectic solvent (DES) consisting of choline chloride and oxalic acid was employed for the surface reconstruction of the PLA filament. Owing to the synergistic contribution effect of physical etching and chemical modification from the DES, the surface roughness and chemical activity of the PLA filament improved significantly, thereby conferring potent low-temperature dyeing performances. The DESmodified PLA filament can achieve K/S value and dye uptake at 90 °C commensurate to those of the PLA filament at 110 °C with no decay on the dry and wet rubbing fastness. This work demonstrates a promising approach for the low-temperature dyeing of PLA filaments, enabling the practical applications of PLA filaments.

Functional textiles with superhydrophobicity and high adhesion to water, called parahydrophobic, are attracting increasing attention from industry and academia. The hierarchical (micronanoscale) surface patterns in nature provide an excellent reference for the manufacture of parahydrophobic functional textiles. However, the replication of the complex parahydrophobic micronanostructures in nature exceeds the ability of traditional manufacturing strategies, which makes it difficult to accurately manufacture controllable nanostructures on yarn and textiles. Herein, a two-photon femtosecond laser direct writing strategy with nanoscale process capability was utilized to accurately construct the functional parahydrophobic yarn with a diameter of 900 μm. Inspired by rose petals, the parahydrophobic yarn is composed of a hollow round tube, regularly arranged micropapillae (the diameter is 109 μm), and nanofolds (the distance is 800 nm) on papillae. The bionic yarn exhibited a superior parahydrophobic behavior, where the liquid droplet not only was firmly adhered to the bionic yarn at an inverted angle (180°) but also presented as spherical on the yarn (the maximum water contact angle is 159°). The fabric woven by the bionic yarn also exhibited liquid droplet-catching ability even when tilted vertically or turned upside down. Based on the excellent parahydrophobic function of bionic yarn, we demonstrated a glove that has very wide application potential in the fields of water droplet-based transportation, manipulation, microreactors, microextractors, etc.