SHARDA UNIVERSITY PHY303-Smart Materials & Devices PHY303-Smart Materials & Devices SBSR, Sharda University, G. Noida, India E mail: Ph. No. :

SHARDA UNIVERSITY Polymer based Nanocomposite *Polymer + *Nano composite

SHARDA UNIVERSITY Polymer * Polymer (Greek Poly & Meros /part) is a large molecule (macromolecule) * composed of repeating structural units typically connected by covalent chemical bonds.

SHARDA UNIVERSITY CLASSIFICATION OF POLYMERS Classification on the basis of origin: 1.NATURAL POLYMERS: ex:Silk, Cellulose 2.DERIVED POLYMERS: derived from natural Polymers ex: cellulose acetate, artificial silk. 3.SYNTHETIC POLYMERS: Synthesis of one or more than one chemical units of low molecular weight ex:PVC,PVA.

SHARDA UNIVERSITY 1.HOMOCHAIN POLYMERS: Ex:Polyethylene is a homopolymer. 2.HETEROCHAIN POLYMERS: Ex:Polyethylene adipate. CLASSIFICATION OF POLYMERS Chain structure:

SHARDA UNIVERSITY 1.LINEAR POLYMERS: molecules are linked in the form of chain. 2.BRANCHED POLYMERS: Molecules having a branched structure. 3.CROSS LINKED POLYMERS: Branches that connect polymer chains. 4.GLOBULAR /SHEET POLYMERS: It contain 2/3-D molecules. Ex:Bakellite. CLASSIFICATION OF POLYMERS Chain Structure:

SHARDA UNIVERSITY On the basis of Processing behaviour: 1.THERMOPLASTICS: Polymers that can be heat-softened into a desired form and shape. Ex: Polyethylene, Polypropylene, PVC. 2.THERMOSET POLYMERS: Initially as liquid,on heating form highly cross-linked solid polymers. Ex: Alkyds, Amino,Polyurethanes. CLASSIFICATION OF POLYMERS (Processing Behavior)

SHARDA UNIVERSITY On the basis of Polymerization Mechanism: CONDENSATION POLYMERS : Small loss of water or other simple molecule like NH 3,HCl,NaCl.etc. Ex:Polyesters,Terylene..etc. ADDITION POLYMERS: Monomers are added involving some kind of active centres. such as free radicals,cations or anions. CLASSIFICATION OF POLYMERS (Polymerization Mechanism)

SHARDA UNIVERSITY On the basis of Forms and Application: PLASTICS: Shaped into hard and tough articles by heat and pressure. Ex: Polystyrene, PVC Elastomers: Vulcanized into rubbery products, exhibit good strength and elongation. Ex: Polyisoprene, Silicone rubber. Fibres: Drawn into long filament, length more than 100times its diameter. Ex: Polyamides, Polyesters. Resins: Used as an adhesive, sealants in a liquid form. Ex: Eepoxy adhesives, Poly sulphide sealants. CLASSIFICATION OF POLYMERS (Forms & Application)

SHARDA UNIVERSITY Classification of Polymer (Conduction behavior) Macromolecules formed by the repetition of a small unit (monomers) Classified as *Insulating Polymers *Semi conducting Polymers *Ion Conducting Polymers or Polymer Electrolytes

SHARDA UNIVERSITY Polymer Electrolytes Classified as * Polyelectrolyte * Solvent Swollen Polymers * Solvent Free Polymer Salt Complex

SHARDA UNIVERSITY Polymer Electrolytes Polyelectrolytes: consisting of their Own Ion Generating Group which is chemically attached to the main chain of polymers. The σ is very low in “Dry State”(  to S/cm.) but Hydrated NAFION has σ very high (  S/cm.) Solvent Swollen Polymers: Some solvent swell in the host matrix like PVA,PVP and dopant ionic solute (like KOH, H 3 PO 4 ) can be accommodated in the Swollen Region. Swollen region which is solvent rich allow ionic motion. PVA+H 3 PO 4 σ  S/cm. Polak et al; 1989 Solvent Free Polymer-Salt Complex: Form of thin film → Solution Cast Tech. → Solution of Polymers & Salts → Mixed/Stirred → Casted into Petridishes → Evaporation of Solvent → Solvent Free Polymer electrolyte Film

SHARDA UNIVERSITY Kevlar (Polymer Fiber) Registered trademark for a para- aramid synthetic fiber, related to other aramids such as Nomex and Technora.trademarkpara- aramidsynthetic fiber aramidsNomexTechnora Developed by Stephanie Kwolek at DuPont in 1965*Stephanie Kwolek DuPont Commercially used in the early 1970s as a replacement for steel in racing tires

SHARDA UNIVERSITY Kevlar (poly paraphenylene terephthalamide) 5 times stronger than steel on an equal weight basis 1964, her group began searching for a new lightweight strong fiber to use for light but strong tires Polymers she had been working with at the time, poly-p-Phenylene- terephthalate and polybenzamide Stephanie Kwolek

SHARDA UNIVERSITY Kevlar (poly paraphenylene terephthalamide) Formed liquid crystal while in solution The solution was “Cloudy, opalescent upon being stirred, and of low viscosity" and usually was thrown away.opalescentviscosity Charles Smullen, who ran the "spinneret", to test her solution, and was amazed to find that the fiber did not break, unlike nylonnylon Spinneret (polymers), a device used to extrude polymers into fibers Spinneret (polymers) Stephanie Kwolek

SHARDA UNIVERSITY Kevlar (poly paraphenylene terephthalamide) Her supervisor and her laboratory director understood the significance of her accidental discovery and a new field of polymer chemistry polymer chemistry By 1971, modern Kevlar was introduced Stephanie Kwolek

SHARDA UNIVERSITY Kevlar (Polymer Fiber) Kevlar is synthesized insynthesized *Solution from the monomers 1,4-phenylene-diamine & terephthaloyl chloride in a condensation reaction yielding hydrochloric acid as a byproduct.phenyleneamineterephthaloyl chloridecondensation reactionhydrochloric acid *Production is expensive because of the difficulties arising in synthesis &spinningspinning

SHARDA UNIVERSITY Graded of Kevlar Kevlar K-29 – in industrial applications, such as cables, brake linings, and body/vehicle armor. Kevlar K49 – high modulus used in cable and rope products. Kevlar K100 – colored version of Kevlar Kevlar K119 – higher-elongation, flexible and more fatigue resistant. Kevlar K129 – higher tenacity for ballistic applications. Kevlar KM2– enhanced ballistic resistance for armor applications [ [

SHARDA UNIVERSITY Structure & Properties *Kevlar is spun, the resulting fiber has a tensile strength of about 3,620 MPa,spuntensile strength Relative densityRelative density of The polymer owes its high strength to the many inter-chain bonds. These inter-mol ecular hydrogen bonds form between the carbonyl groups and NH centers.hydrogen bonds Kevlar's structure consists of relatively rigid molecules which tend to form mostly planar sheet-like structures rather like silk proteinsilk

SHARDA UNIVERSITY Preparation (Polymer Nano Composites)

SHARDA UNIVERSITY Infrared Spectroscopy (to check complex formation & composite formation) The IR of Complexed PEO does not contain the specific bands of NH 4 I located exactly at the same wavenumber i.e complexation is complete and no unreacted NH 4 I remains ☞ Shifting of peaks positions ☞ No new peaks *NH 4 I has complexed with PEO to form a polymer electrolyte. *Composite

SHARDA UNIVERSITY XRD complete complexation reduced in crystallinity no additional peaks of KI in c

SHARDA UNIVERSITY Industrial Application of Polymers

SHARDA UNIVERSITY Industrial Application of Polymers

SHARDA UNIVERSITY