Students can go through AP Inter 2nd Year Chemistry Notes 8th Lesson Polymers will help students in revising the entire concepts quickly.
AP Inter 2nd Year Chemistry Notes 8th Lesson Polymers
→ Polymer : A polymer is the very large molecule having high molecular mass formed by the joining of repeated simple reactive structural units (monomers). This process is known as polymerisation.
→ Based on source polymers are classified into natural, semi-synthetic, synthetic polymers.
→ Based on structure polymers are classified into linear, branched, cross linked polymers.
→ Based on mode of polymerisation polymers are classified into addition, condensation polymers.
→ Based on molecular force polymers are classified into elastomers fibres, thermoplastics, thermosetting polymers.
→ The polymer which is formed by the polymerisation of chemically two (or) more different mononiers is called co-polymer.
→ The process of heating the natural rubber with sulphur (or) with sulphur compounds to improve the properties of rubber is called vulcanization of rubber.
→ Homopolymers of 1, 3 – Butadiene derivatives (or) co-polymer of 1, 3-Butadiene (or) its derivatives with another unsaturated monomer are called synthetic rubbers.
→ The average molecular masses of polymers expressed in
- Number average molecular mass (\(\overline{\mathrm{M}}_{\mathrm{n}}\))
- Weight average molecular mass (\(\overline{\mathrm{M}}_{\mathrm{w}}\))
→ Poly dispersity index (PDI) : The ratio between weight average molecular mass (\(\overline{\mathrm{M}}_{\mathrm{w}}\)) and number average molecular mass (\(\overline{\mathrm{M}}_{\mathrm{n}}\)) of a polymer is called poly dispersity index (PDI).
→ Biodegradable polymers : The polymers degraded by enzymatic hydrolysis (or) by oxidation are called biodegradable polymers.