Polymer Fundamental

  Introduction There is always confusion among most of the people about bioplastic and biodegradable plastic. Most of the people make mistake by considering bioplastic are same as biodegradable plastic. The bio based plastics are plastics made from biomass, generally related to the use of plants as feedstock. Given their natural origin, one could erroneously assume that these plastics are also biodegradable . However, biodegradability depends on the properties of the plastic at hand, including chemical structure and crystallinity. Polymers are derived from bio-based monomers that subsequently undergo chemical reactions to become bio-based polymers. For Example 1.        The bio polyesters PLA and PEF, 2.         Sugarcane-based bio polyethylene, 3.         Nylon 4/10 and 11, which are derived from castor oil. Bio Based polymers are naturally occurring polymers such as Cellulose...

  Biodegradable Plastic Introduction P lastic is known from long time. In 19 th century Europe and America has invented synthetic plastic. During World War II, Nylon played major role. Since then invention in plastic has done in various part of world. Consumption of plastic during World War II was 1.7 kg per person; in 2007 it was almost 100 Kg per person. Now it is reached to 150 Kg per person. Plastic has several benefits over metal and paper. Their low energy requirement in production, corrosion resistance, and light weight, durable make them unique. In food packaging, it increases food shelve life without using preservative. Today, synthetic plastic faces problem due to health issues. To run the multibillion dollar business industry is looking for new product called biodegradable plastic. Biodegradable plastics are  plastics  that can be decomposed by the action of living organisms, usually microbes, into water, carbon dioxide, and biomass .  Bio d...

                              Polymeric Chemical Reaction Polymer can be further classified by the type of chemical reactions which the monomers undergo in producing molecular weight compounds. 1.        Poly condensation reaction –Monomers react by repeated splitting off H2O, NH3, CH2O, NaCl, or other small molecules on a step by step reaction to build of the molecular size. 2.        Addition reaction – occurs among molecules containing double or triple bonds or with oxo-ring compounds. No small molecules are liberated and reaction is the rapid chain type. A.       Poly condensations Reactions. a.        Representative groups                         ...

Polymers are difficult to classify because there are so many interacting relationship among the large number of polymeric materials now in existence. Four most methods of classifications are 1.        Physico chemical structure 2.        Mode reparation 3.        Physical properties 4.        Technical applications   A.       Physico Chemical structure                 Functionality: - The ultimate result of coupling monomers to produce polymers is wholly dependent on the functionality of monomer. Molecule is called Mono-, bi-,tri-, or polyfunctional depending on the number of reactive bonds or groups available for coupling at beginning or during course of polymeric reaction. 1.        Unifunctional   (U-), Exampl...