A Study on Preparation and Property Evaluations of Composites Consisting of TPU/Triclosan Membranes and Tencel®/LMPET Nonwoven Fabrics

Sustainable polylactic acid spunlace nonwoven fabrics with lignin/zinc oxide/water-based polyurethane composite coatings

In this paper, polylactic acid spunlace nonwoven fabrics were coated with lignin/zinc oxide/water-based polyurethane composite formulations, including five different ratios of lignin and zinc oxide, via a film applicator and thermally cured. The coated and thermally cured nonwoven fabrics were tested in terms of color values, tensile strength, abrasion resistance, ultraviolet protection, hydrophobicity, antibacterial activity, air, and vapor permeability properties. Characterization studies were conducted by FTIR, DSC, TGA, XRD, and SEM. The ultraviolet protection factor of 215.47 and a water contact angle of 90.27° were obtained with the fabric coated with WPU-1:5 formulation. Nonwoven fabric coated with the WPU-1:5 formulation showed evident antibacterial activity against S. aureus and E. coli bacteria as 89 % and 100 %, respectively. With the addition of lignin/ZnO into water-based polyurethane coating paste, PLA nonwoven fabric exhibited improved antibacterial activity, tensile strength, abrasion resistance, and ultraviolet light protection performance. However, composite coatings decreased air and vapor permeability and hydrophobicity of fabrics, but acceptable results were obtained. The results indicate that polylactic acid nonwoven fabrics, when treated with lignin/ZnO/WPU composite coatings, exhibit enhanced mechanical and functional properties, rendering them promising for applications in protective medical textiles.

Synthesis and Characterization of New Polycarbonate-Based Poly(thiourethane-urethane)s

The new segmented poly(thiourethane-urethane)s (PTURs) based on 1,1′-methanediylbis(4-isocyanatocyclohexane) (HMDI, Desmodur W^®), polycarbonate diol (PCD, Desmophen C2200) and (methanediyldibenzene-4,1-diyl)dimethanethiol were synthesized by one-step melt polyaddition method. The obtained PTURs, with a content of 30–60 wt% of the hard segments (HS), were tested in which the influence of changes in the HS content on their properties was determined. The polymers were characterized by Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), thermal analysis (DSC, TGA) and thermomechanical analysis (DMTA). Additionally, tensile strength, optical (refractive index, UV-VIS and color) and surface properties of the obtained polymers (contact angle and surface free energy) and adhesion to copper were examined. FTIR analysis verified the supposed structure of the polymers obtained and showed a complete conversion of the isocyanate groups. TGA analysis confirmed the relatively good thermal stability of the polymers. On the other hand, after performing the DSC analysis, it was possible to state that the obtained materials were partially or completely amorphous, and the microphase separation decreased with increasing HS content in the polymer. Similar observations were made from the DMTA data. In addition, the hardness, tensile strength, modulus of elasticity, storage modulus, adhesion to copper, refractive index and total free surface energy increased with increasing HS content in the polymer.