3.02 Study, application and characterization of eco-friendly solutions for textile finishing

Preamble
This project relates to Task 3.4.1 “Functionalisation of consumer products to highly-efficient, eco-friendly materials” of the Made in Italy Circolare e Sostenibile (MICS) Extended Partnership project.
Key elements of the project
The textile sector, both traditional and technical, is constantly evolving. Made in Italy requires an increasing use of innovative technologies but, above all, of highly efficient and ecological products and processes. It is therefore crucial to impart chemical, natural, and sustainable functionalization to provide the textile materials with most varied properties and, at the same time, to use waste as secondary raw materials.
To promote greater sustainability of the textile supply chain, this project proposal aims to study, develop, and characterize bio-based treatments for textile substrates of both natural and synthetic origin.
In response to the growing demand for sustainable textile materials, formulations with components of natural origin (up to 75%) will be selected, using as a criterion the relative availability in the market that ensures their immediate industrial scalability. Furthermore, these products will be chosen with the aim of identifying useful compositions for the development of matrices through which to propose functionalizing finishes (antibacterial, flame retardant, water repellent, photo-catalyst and, more generally, films with barrier effects).
The main objectives to be achieved concern, in particular:

• development of eco-friendly or bio-based formulations (according to EN 16575:2014) to achieve innovative textile finishing treatments;
• evaluation of the stability of the above-mentioned products;
• achieving of the performance properties of the treated fabrics, set as part of the designed activities, including durability to maintenance cycles.
  Treatments will be developed using two leading technologies: impregnation and extrusion. The former will be employed for all substrates and the latter exclusively for polymers of synthetic origin.
  Expected outcomes
  Development of advanced functionalization of textiles using natural and/or environmental-friendly products to give antibacterial, flame retardant, wear-resistant, water-repellent, photo-catalytic and conductive properties.
  Work Plan
  The project will be broken down into complementary activities, each with identified leading Partner:

1. Synthesis and application of bio-based formulations (leader UniBg)
   Selection of representative textile fabrics on the market from natural and synthetic sources. Evaluation of the final performance requested for textiles. The combined use of bio-based polymers (e.g., proteins, polysaccharides, acids) and sol-gel precursors will be performed (in collaboration with CNR) and evaluated to develop new sustainable multicomponent bio-based coatings. Selection and development of formulations containing bio-based products and sol-gel precursors. Application of developed formulations onto textile fabrics by impregnations.
2. Yarns functionalization by extrusion (leader PoliMi)
   Yarn functionalization can be performed in mass using reactive extrusion, without solvents, to obtain fibers with different properties like antibacterial, hydrophilicity or hydrophobicity.
3. Characterization of treated textile materials (leader CNR)
   Chemical-physical, mechanical, and morphological characterizations will be done, comparing treated and untreated textiles (yarn and fabrics). Among others, the following characterizations will be performed:
   Chemical properties: thermal analysis (DSC, TGA), chemical composition of surfaces (XPS, elemental mapping by SEM-EDX), determination of charge of surfaces (Surface zeta potential, Raman mapping, ATR).
   Mechanical properties: tensile strength, tear strength, wear resistance.
   Barrier properties: air permeability change, thermal stability, water repellency.
   Washing fastness: durability of the finishings according to the standard textile test.
   Morphological properties will be studied by optical and electronic microscopy. Biological tests for evaluating the inhibition of the growth of bacteria and quantifying bactericidal behaviour will be considered.