Polymers

• Polymer defined as macromolecule made from simple molecules which may be same or different and are characterized by repeating units in a linear sequence held together by covalent bonds.
• Monomer is a simple molecule having one or more reactive functional group which compounds with same or different molecule to form high molecular weight polymer.
• Polymerization is a process in which large number of similar or different simple molecules of low molecular weight (monomer) combined to form a giant macromolecule of high molecular weight (polymer).
• Classification of polymer:-

  1. Based on Origin: A. Natural B.Synthetic
  2. Based on monomers: A.Homopolymermer B. Copolymer
  3. Based on Properties: Plastic, A. Thermoplastics, B. Thermosets
• StereoChemistry: in a branded polymer the side chain can have different arrangement with respect to polymer chain, thus due to the difference in steric arrangement the polymer show stereochemistry
• Tacticity: it is defined as difference in spatial arrangement of side chain on the polymer chain leading to the stereoisomerism. Types of Tacticity- Isotactic, Syndiotactic,
• Biodegradable polymers are the polymers which can be degraded by microorganisms like bacteria, fungi, algae etc which are naturally present in the environment these polymers are broken into smaller parts by reaction catalyzed by the enzymes produced by microorganisms.

  1. Cyclic Ketal
  2. Polyhydroxy Alkanoates
• Cyclic Ketal:-

  The CC bond in polymer like PE, PS, and PP to enzymes catalyzed reaction and hands they are non biodegradable.

  However is small amount of cyclic ketal are added to the alkenes during polymerization will insert an ester group(COO-) in the polymers this will weaken the link and make them biodegradable.
• Polyhydroxy Alkanoates:-

  Polyhydroxy Alkanoates are the biodegradable bacteria in the soil that can readily degrade polymer in the presence of oxygen from CO2 and water biodegradation depends on moisture and pH of the soil.

  Similar to the cyclic cattle if polyhydroxy alkanoates are added to alkenes during the polymerization it will insert ester group in the polymers and we can the link between them and make them biodegradable.