Polymers and its applications

Polymers and its applicationsACKNOWLEDGEMENTI take this opportunity to present my votes of thanks to only those guidepost who in reality acted as lightening pillars to enlighten our way passim this project that has led to successful and satisfactory completion of this study. We be really grateful to our HOD for providing us with an opportunity to undertake this project in this university and providing us with all the facilities. We atomic number 18 highly thankful to Mr. Harminder Singh for his active support, valuable age and advice, whole-hearted guidance, sincere cooperation and pains-taking involvement during the study and in completing the assignment of preparing the utter project within the time stipulated.Lastly, We are thankful to all those, curiously the various friends who have been instrumental in creating proper, healthy and conductive purlieu and including new and fresh innovative ideas for us during the project, their help, it would have been extremely unmanag eable for us to prepare the project in a time give frameworkHISTORY-Polymers were discovered long before anyone understood what they were. It wasnt until 1920 that German chemist Hermann Staudinger (1881-1965) do his macromolecular hypothesis, suggesting that polymers are actually giant molecules organise by the permanent attachment of countless smaller molecules.INTRODUCTION-A polymer is a large MOLECULE undisturbed of repeating structural typically connected by chemical constipates like covalent bonds. Polymers are composed of very high molecular circlees organise by the faction of large number of simple molecules.GEOMETRY-Polymers (or macromolecules) are very large molecules made up of smaller units called monomers or repeating units, covalently bonded to get outher.Monomers / Repeat UnitsThe identity of the monomer residues (repeat units) comprising a polymer is its first and most important attribute.Microstructure-The microstructure of a polymer (sometimes called confi guration) relates to the physical arrangement of monomer (which I have explained above) residues along the backbone of the chain.CLASSIFICATION OF POLYMERS-On the basis of structure- running(a) POLYMERS BRANCHED POLYMERSCROSS-LINKED POLYMERSOn the basis of molecular forces Elastomers Fibers ThermoplasticsThermosetting polymersThermoplastsThese are the polymers which gouge be easily softened repeatedly when heated and hardened when cooled with comminuted change in their properties. When heated due to the absence of cross cerebrate, they make out free to move and and can be moulded into any desired shapes.EXAMPLES- Polyvinyl Chloride (PVC) and Polystyrene and Polymethyl methacrylateThermosets-These are the polymers which undergo permanent change on heating and can non be remoulded into our desired shape. On heating their cross links get highly linked with each other and deforms hard and infusible.EXAMPLES-Bakelite,formaldehyde etc.PROPERTIES- flexible strengthHigher tensile stre ngth holds a greater encumbrance before snapping. Tensile strength increases with polymer chain length and crosslinking of polymer chains.Melting occlusionThe term melting point when applied to polymers, suggests not a solid-liquid anatomy transition but a transition from a crystalline or semi-crystalline phase to a solid amorphous phase.Boiling pointThe simmering point of a polymeric material is strongly dependent on chain length. The polymers with a large degree of polymerization do not exhibit a boiling point be relieve oneself they are decomposed before reaching their respective theoretical boiling point.FUN FACT The polymer inside disposable diapers is called sodium polyacrylate. It can instantly absorb roughly 800 times its mass in water.APPLICATIONS OF POLYMERS-Molecular science has developed enormously in new-fashioned eras. Molecular science has a major role in our lives. It has become a necessity in our daily routines we shall talk now about the basic applications o f polymers without which life wasnt that easy. We are going to discuss some of the main polymers use in our lives.RUBBER-HISTORY OF RUBBER Natural prophylactic, obtained from the conk out of the hevea tree. Rubber was named by the chemist Joseph Priestley who found that a cull of solidified latex gum was good for rubbing out pencil marks on paper.TWO TYPES OF RUBBER ARE THERE- intrinsic RUBBERVULCANIZED RUBBER (SYNTHETIC RUBBER)NATURAL RUBBER-Natural no-count is a polymer of isoprene (2-methyl-1, 3-butadiene), with a joined network structure.There is no cross links in the midst of the polymer chains. It is not hard and gruelling. It becomes sticky and soft when heated. It can be easily deformed but regains its original shape after the sift is released. It involves a addition reaction in which one double bond in isoprene open to form a new bond with undermentioned unit forming a large chain.VULCANIZED RUBBER-.A chemical reaction of sulfur (or other vulcanizing agent) with ru bber or plastic to cause cross-linking of the polymer chains it increases strength and resiliency of the polymer chemically the process involves the formation of cross-linkages between the polymer chains of the rubbers molecules. It was invented by Charles Goodyear in 1839.The formation of cross links formed at the time of vulcanization at the reactive sites makes rubber hard, tough with greater tensile strength. It has very high elasticity, resistance to oxidation and thoroughgoing solvents. The sulphur bridge in this figure prevents the slip of the chains and rubber can be stretched to a limited extent and when tension is removed(p) the chains try to coil up regain its original shape. other(a) TYPES OF RUBBER-NEOPRENE RUBBER-USES employ as insulator, devising conveyor belts, printer roller belts are also made from it.SBR (Styrene Butadiene Rubber)-Known as BUNA-SUSES it is used for qualification automobile tyres and footwears.NITRILE RUBBER- Recognized as BUNA-NUSES-it is used for making oil seals, manufacture of hoses and tank linkings.REACTIONS INVOLVING IN THERE FORMATIONS-PLASTICS OR POLYHALO-OLEFINS-A very useful but common commodity of our life. But present it has become a serious problem due to its problem of degradation which is a process which is a time consuming process. These are called polyhalo-olefins because they are derived from halogen substituted olefins.POLYVINYLCHLORIDE-(PVC)-Its monomer is unit is vinyl chloride. it is prepared by heating vinyl chloride in an inert solvent in the presence of peroxides (eg.dibenzoyl peroxides).It isa hard horny material. It is a thermoplastic polymer and its plasticity can be increased . Fig 15.0USES-It is used in manufacturing of rain coats, hand bags, curtain clothes, toysArtificial flooring.As a good insulating material in wires and other electrical goods.For making gramophone records.TEFLON-(POLYTETRAFLOUROETHYLENE)Tough material resistant to heat and chemical actions such as acids and bases. It is an addition polymer of tetraflouroethylene.It is bad conductor of heat.USESIt is used as a material resistant to heat and chemical attack in class works.For coating articles and cookware to make them non-sticky as non stick utensilsFor making gaskets, handle packaging, valve, seals, non-lubricated bearings, etc.POLYESTERS-Fibers represent a very important application of polymeric materials, including many examples from the categories of plastics and elastomers.It involves ester linkagesTYPES OF POLYESTERS(FIBRES)-TERYLINE-It is a polymer of ethylene glycol and terephthalic acid. Also known as Dacron.USES-For making cloth by mixing with cotton.For making magnetic written text tapes.NYLON66-Monomers are hexamethylenediamine and adipic acid.USES-Used for making bristles of brushes.In textiles and also for making sheets. It is mix with wool to make socks and sweaters.NYLON 6- its monomer is caprolactum made up of cyclohexane.USES-It is used in the manufacture of tyre ,cords, fabrics, and ropes.CONCLUSION-We have tried to give a brief information on polymers .Polymers are everywhere around us and we tried to show a glimpse of polymers applications which are commonly used in our lives like plastics nylon and day to day used commodities.MATERIAL AND enroll REFRENCES-http//www.plastiquarian.com/top.htmhttp//www.csua.berkely.edu/ranga/school/me223/nylon.gifhttp//www.openlearn.open.ac.uk/course/view.php?id=2937http//www.britanica.com/EBchecked/topic/468696/polymerhttp//www.polymertalk.com/history_of_polymers.phphttp//en.wikipedia.org/wiki/siliconehttp//en.wikipedia.org/wiki/branching_%28chemistry%29 http//www.polymertalk.com/classification_of_polymers.phphttp//docs.google.com/viewer?a=vq=cacheWbn5XOJDtwww.cmse.ed.ac.uk/MSE3/Topics/MSE3-polymers.pdf+intoduction+of+polymershl=engl=insig=AHIEtbQ22RNSIoIyoXUP9HtDd-nakz-whttp//www.cem.msu.edu/reusch/VirtualText/polymers.htm