1. WOOL KERATIN-BASED NANOFIBRES FOR ACTIVE FILTRATION OF AIR AND WATER A. Aluigi, C.Vineis, A. Varesano, C. Tonetti, C. Tonin, G.Mazzuchetti. 2 nd International Conference on Innovative Natural Fibre Composites for Industrial Applications Rome, April 15-18, 2009 INSTITUTE FOR MACROMOLECULAR STUDIES

2. High Cysteine Content Protein (7-20% of the total aminoacids) WoolFeather Horns, Nails Hair KERATINS

3. KERATIN WASTES: Renewable Source > 5.000.000 tons/year of keratin wastes from  By-products of the textile industry  Poor quality raw wool not fit for spinning  Hairs and feathers from butchery

4. Intermidiate Filaments LS  Low-Sulphur Content Keratin (1,5 -2 %wt) (LS)  MW: 60, 45 kDa   -Helix Structure Cuticle HS  High-Sulphur Content Keratin (8%wt) (HS)  MW: 28-11 kDa   Sheet-Disordered Structures Matrix HS  High-Sulphur Content Keratin (8% wt) (HS)  MW: 28-11 kDa  Disordered Structure Wool Fibre

5. AIM Nanofibre Non-Wovens Filtration System Air Cleaning Water depuration: especially removal of ultrafine particles and heavy metals adsorption Keratin from Wool [1] P. Kar and M. Misra, J. Chem. Technol Biotechnol, 2004, 79, 1313-1319 [2] X. Huang, Y. J. Wang and Y. H. Di, Textile Research Journal, 2007, 77(12), 946-950 Properties of regenerated wool keratin Heavy metals absorption [1] Formaldeyde absorption [2] Nanofibre non-wovens properties High surface/volume ratio High porosity

6. Nanofibre Production by Electrospinning Basic setup for an electrospinning apparatus High voltage supplier [10  30 KV DC] Syringe with a small diameter needle [0.2  1.5 mm] Metal collecting screen Electrostatic forces Elongational forces able to transform the polymer solution in nanofibres

7. Keratin Extraction from Wool + metabisulphite [0.6M]; Urea [8M]; SDS [0.02M]; pH 6.5 Shaking, 65°C, 2h Filtration Solid Fraction Liquid Fraction Keratin/H 2 O Casting 50°C overnight Regenerated Keratin Film Dialysis Filtration 5  m LS HS

8. Keratin PA 6 20 kDa Regenerated Keratin Characteristic Poor mechanical properties Non-Thermoplastic Common solvent use (volatile) Polymer Blend Used to produce filters

9. Keratin/Formic Acid Solution Stability Keratin / Formic Acid 1Standard Keratin regenerated from formic acid: 22 days 3After two weeks 4After 1 month 5After 3 months Extracted Keratin in Formic Acid 5% wt Casting 50°C overnight Films of Keratin regenerated from Formic Acid SDS-PAGE

10. Regenerated Keratin in Formic Acid 15% wt + Polyamide 6 in Formic Acid 15% wt Blends0/10010/9030/7050/5070/3090/10100/0 CastingFilm Electrospinning NanofibreNon-Woven

11. Blend solution decanted overnight Cryogenically fractured sections of blend films Viscosity Immiscibility between keratin and polyamide 6 Additivity Rule Solution Properties

12. Electrospinning Conditions Flow Rate (ml/min): 0,001 0,005 0,01 Voltage (kV): 15 20 25 30 Tip-to-Target Distance (cm): 10 Capillary (mm): 0,40

13. Nanofibre Morfology Beads

14. Diameter Size Distributions of Blend Nanofibres

15. 1 day immersion in water Water Stability

16. [Cr +3 ] 0 =50  g/L pH=4 Stock Solution Preliminary test of chromium adsorption

17. Formaldehyde Adsorption

18. Formaldehyde Adosrption Apparatus Multicomponent filter made of nanofibres deposited in a PP filter sheet Chamber containing 0.6 ppm of formaldehyde Formaldehyde releasing silica Formaldemeter TM

19. Decrease of formaldehyde concentration with an initial concentration of 0.6 ppm (100%) during time in the presence of filters Tests performed at 20°C and 65% r.h. Physiosorption + Chemisorption

20. CONCLUSIONS  Keratin/Polyamide 6 blend solutions in different proportions were prepared using formic acid as a common solvent  Morphological analysis and viscosity measurements suggest immiscibility between the two polymers  All the blend solutions were suitable for electrospinning and thin nanofibres with diameter ranging from 70 to 300 nm were obtained  The stability in water of keratin/polyamide 6 blend nanofibres decreases with increasing the keratin content  Keratin based nanofibres show a good chromium adsorption capacity  Keratin based nanofibres are good formaldehyde absorbers, reducing airborne formaldehyde concentration up to 70%

21. … ALL of YOU for your attention!! …REGIONE PIEMONTE (HI-TEX Project) and CASSA DI RISPARMIO DI BIELLA Foundation for the financial support