Chuah Shu Chin Fariza Fuziana bt Yacob Lim Weng Keat Low Mei Ching Mohamad Azrul Drahman Mohd Zaidan bin Abdul Aziz Sawita binti Amir B050810194 B050810220 B050810181 B050810215 B050810178 B050810281 B050810051 •Nanostructured composite fiber are in one area where we see the early blooming of nanotechnology. •Most of the nanocomposite fibers use fillers: Nanoparticle Graphite nanofiber CNTs •Nano-sized that used to improved the performance of in textiles are: Carbon nanofibers and carbon black nanoparticle Clay nanoparticle Metal oxide nanoparticle Carbon nanotubes. Nanofiller Carbon nanofibers and carbon black nanoparticle Clay nanoparticle Properties High chemical resistance Electrical conductivity Effect on the textiles Carbon black- improved abrasion resistance and toughness Nanofiber- increased tensile strength Electrical, heat and chemical resistance Block UV light Flame retardant, anticorrosive Improved tensile strength, tensile modulus, flexural strength and flexural modulus Metal oxide Photocatalytic ability nanoparticle Electrical conductivity (MgO, ZnO) UV absorption Carbon nanotubes Incorporating ZnO into nylon produce composite fiber that shield UV light and have antistatic properties Good thermal conductivity Increased toughness and stiffness Electrical conductivity 100x tensile strength of steel Electrospinning Deposition layer of coating onto the surface of fiber • Charge polymer melt is extruded through a small nozzle (needle or pipette tip) • The charged is drawn toward grounded collecting plate (meta screen, plate or mandrel) • As the jet travel, solvent evaporates leaving a non-woven nanofiber • The thickness of each layer is in nanometer range • A number of methods have been used to apply a nanocoating to the fiber surface Developments of nanotechnology in textiles 1) Upgrading existing functions in performances of textile materials 2) Developing smart & intelligent textiles with unprecedented functions Stainresistant Odour control UVprotection Ultrahydrophobic/ Water resistant TEXTILE PERFORMANCES Antimicrobial activity Antistatic Wrinkle resistant Shrink proof Antimicrobial activity Antimicrobial body wear: customer awareness of hygiene odour control medical applications (e.g. Neorodermatitis) silver nanoparticles in the fiber silver nano-coating high washing fastness Nano-sized Ag, TiO2 & ZnO are used to impart anti-bacterial properties. Nano-Ag particles have an extremely large specific surface area, thus increasing their contact with bacteria or fungi & vastly improving their bactericidal and fungicidal effectiveness (Zgondek, 2008). The textile structure & application of nanotechnology on antimicrobial activity (Beringer, 2005) UV-protection How to improve UV protection factor (UPF) of textiles Fabric design -Tighter weaving or knitting -Higher weight Textile finishing -Organic dyes absorbing UV light - Optical brighteners (in detergents) - Dark coloration Photo catalysis mechanism of TiO2 (Source: Samal et al., 2010) Fibermodification -TiO2, ZnO nano pigments for dulling of chemical fibers -Coating – to prevent photocatalytic reactions Fiber Raw Materials: 1) Polyester (PET, PPT, PBT) 2) Polyamide (PA 6, PA 6,6) 3) Natural fibers (CO, WO, LI) (Source: Beringer, 2005) Anti-static Material: nano-ZnO not only it repel static, but also repels statically attractive substances (e.g. dog hair, lint & dust) (Hauser, 2006). Textiles that resist static (Source: Hauser, 2006) Method: direct precipitation with zinc chloride & sodium carbonate anhydrous as raw materials. Cotton fabric & polyester fabric: finished by pad-dry-cure process with antistatic finishing agent (compounded with nano-ZnO). The charge density of the density of the polyester fabric is about 10 times as that of the cotton fabric (Fan and Junling, 2009). Ultrahydrophobic/ Water resistant Method to fabricate ultrahydrophobic textile materials: cobinations of polystyrene grafted layers (low surface energy component) & silver/silica/calcium carbonate nanoparticles (roughness initiation component) Static water contact angle on (a) PET fabric grafted with PS only (no silver) (b) ultrahyrophobic fabric Stainresistant Method: Admicellar polymerization -involves emulsion polymerization -durable finishes: high performance in stain resistance & repellency (Hanumansetty, 2012) Figure 9: Stain resistance for untreated and treated fabric with PA2 with different staining agents (Hanumansetty, 2012). The mechanism of self-cleaning textile (Source: Samal et al., 2010). The self-cleaning surface by lotues effect. Odour control Cyclodextrins can be incorporated into a fabric finish to remove odour. Cyclodextrins have a unique molecular structure, composed of a hydrophobic cavity, with a hydrophilic exterior. The mechanism of odour control by applying an antimicrobial finish (Source: Hauser, 2006) Wrinkle resistant Resin treated cotton. Resins are used to make the cotton wrinkle free. The resin treatment also blocks cotton’s natural ability to absorb moisture (Hauser, 2006). Shrink proof Deficiency of wool - shrinkage (felting) & pilling. Chemical treatment Plasma treatment Treatments & methods of application Cyclodextrin sericin treatment Enzymatic treatment The hydrophobic nature & scale structure of the wool fiber lead to the fiber to move towards their root end under mechanical action in the wet state. Chemical treatments: 1.Coating with resins (e.g. Polyamide epichlorohydrin) onto wool fibers. 2.Morphological modification of the cuticular (protective/outer cellular layer) cells. Nano-particles such as metal oxides and ceramics are also used in the textile finishing to alter surface properties and impart textile functions. Nano size particles have a larger surface area and hence higher efficiency than larger size particles. Besides, nano size particles are transparent and do not blur color and brightness of the textile substrates. Continued… The fabric treated with nano-particles TiO2 and MgO replaces fabrics with active carbon, previously used as chemical and biological protective materials. The photo-catalytic activity of TiO2 and MgO nano-particles can break harmful and toxic chemicals and biological agents. These nano-particles can be engineered to adhere to textile substrates by using spray coating or electrostatic methods. ZnO nano-particles: By using a simple water-based technique, ZnO nano particles was dispersed inside a soluble starch matrix. Water are used as a solvent in synthesis of nano-particles that causes an immediate agglomeration due to high polarity of water. To overcome agglomeration, soluble starch was added before the reaction starts. Zinc oxide (ZnO) nanoparticles embedded in polymer matrices like soluble starch are a good example of functional nanostructures with potential for applications such as UV-protection ability in textiles and sunscreens, and antibacterial finishes in medical textiles and inner wears. Nanoparticles are applied to textiles and fixed to the substrate by the use of functional polymers. (e.g. modified polyamines, polyethylene imine, star-shaped prepolymers with isocyanate groups, epoxides, acrylic acid esters, fluoropolymers etc.) SUMMARY: Simple Water-based Technique modified polyamines, polyethylene imine, epoxides, acrylic acid esters, fluoropolymers SELF ASSEMBLED NANOLAYERS (SAN) INTRODUCTION • Challenge to traditional textile coating. • Still in embryo stage. • Target chemical molecules form a layer of thickness < nanometer on the surface of textile materials. • Additional layers Top of the existing ones = Nanolayered structure ELECTROSTATIC SELF-ASSEMBLY • WHY ELECTROSTATIC SELF ASSEMBLY? Protective function Self-healing function Flexibility Compatibility Environmental friendly ELECTROSTATIC SELF-ASSEMBLY (CONT…) Dipping a positively charged substrate into a dilute aqueous solution of an anionic polyelectrolyte. Allowing the anionic polymer to adsorp on the surface. The negatively charged coated substrate is rinsed and then dipped into a solution of cationic polyelectrolyte. Multilayer films are created. Polyelectrolyte Adsorption • Surface phenomenon where long-chained polymer molecules with charged groups bind to a surface that is charged in the opposite polarity. • The polymers bonds to the surface via intermolecular forces and the charges created by the dissociation of various side groups of the polymer. • Because the polymer molecules are so long, they have a large amount of surface area with which to contact the surface and thus do not desorb as small molecules are likely to do. This means that adsorbed layers of polyelectrolytes form a very durable coating. • By kinetic control of adsorption , film thickness and growth can be controlled. The film was constructed by the sequential adsorption of oppositely charged species in a layer-by-layer fashion from dilute solutions. The surface coverage increases linearly with the number of deposition steps. Entropy of polymer chains Hydrogen bond Charge transfer interactions Molar mass Factors of Electrostati cs Selfassembly Hydrophobic interactions Flexibility of chains Ion exchange capability What are the potential applications of highly water repellent textile materials? Rainwear - repel the water during raining day Upholstery – textile used to cover the furniture Sportswear Protective clothing Automobile interior fabric What is the application of nanotechnology for textile in military? Lightweight bulletproof vests and shirts Nanotechnologists have come up with a super strong, flexible fiber that can conduct heat and electricity. It could be made into a modern version of chain mail, the heavy metal mesh worn by medieval knights. If woven from the new fiber, modern chain mail could be light as a cotton shirt, but bulletproof. chain mail modern version of chain mail What are the future prospects and new functions in textiles to be developed? Future Prospect • Two focus: – Upgrading existing functions and performances of textile materials. – Developing smart and intelligent textiles with unprecedented functions. The new functions with textiles to be developed: Wearable solar cell and energy storage Multiple and sophisticated protection and detection Sensors and information acquisition and transfer The new functions with textiles to be developed: Health-care and wound healing functions Self-cleaning and repairing functions REFERENCES Lei, Q. and Hineroza, J.P., 2004. Application of Nanotechnology for High Performance Textile. Journal of Textile and Apparel, Technology and Management, 4 (1), pp.1-7. Ramaratnam, K., Iyer, S.K., Kinnan, M.K., Chumanov, G., Brown, P.J. and Luzinov, I., 2008. Ultrahydrophobic Textiles Using Nanoparticles: Lotus Approach. Journal of Engineered Fibers and Fabrics, 3 (4),pp.1-14. Fan and Junling, 2009. Preparation of Nano-ZnO and Its Application to the Textile on Antistatic Finishing. Internantional Journal of Chemistry, 1 (1), pp.1822. Jeevani, T., 2011. Nanotextile – A Broader Perspective. Nanomedicine & Nanotechnology, 2 (7), pp.1-5. Hanumansetty, S., Maity, J., Foster, R. and O’Rear, E.A., 2012. Stain Resistance of Cotton Fabrics before and after Finishing with Admicellar Polymerization. Applied Science, 2 (10), pp.192-205. Zgondek, E.M., Bacciarelli, A., Szynkowska, M.I. and Kolodziejczyk, M., 2008. Antibacterial Properties of Silver-Finished Textiles. FIBRES & TEXTILES in Eastern Europe, 16 (5), pp.101-107. REFERENCES (cont.) Beringer, J., 2005. Nanotechnology in Textile Finishing – State of the Art and Future Prospects, Germany: Hohenstein Institute. Hauser, P., 2006. Advances and Trends in Textile Wet Processing Chemicals. Journal of Textile and Apparel, Technology and Management, 5 (1), pp.1-4. Samal, S.S., Jeyaraman, P. and Vishwakarma, V ., 2010. Sonochemical Coating of Ag-TiO2 Nanoparticles on Textile Fabrics for Stain Repellency and Self-Cleaning-The Indian Scenario: A Review. Journal of Minerals, Materials Characterization & Engineering, 9 (6), pp.519-525. Allam, O.G., 2011. Imrpoving Functional Characteristics of Wool and Some Synthetic Fibers. Open Journal of Organic Polymer Materials, 3, pp.8-19.