Classification of Copolymers:

They are classified as:

1. Classification based upon source of availability.
2. Classification based upon structure.
3. Classification based upon mode of polymerisation.
4. Classification based upon molecular forces.

1. Classification based upon source of availability

• Natural Polymer:- Found in nature e.g. in plants etc.
• Semi-Synthetic:- Derived from naturally occurring sub by chemical modification e.g. Vulcanized  Rubber.
• Synthetic Polymer:- Man made polymers e.g. Nylon, PVC

2. Classification based upon source of structure

• Linear Polymers:- Monomers are joined to form long straight chains. They can be stacked over one another. Because of close packing of polymers chains, they have high M.P, high density and high tensile straight. e.g. PVC (Poly Vinyl Chloride), Nylons.
• Branched Chain Polymers:- Monomers units form linear chains & their branches also of different length. But they do not pack well so have lower M.P, Lower strength. e.g. Glycogen.
• Cross Linked or 3-D Network Polymer:-  In this linear chain polymers are joined together to form 3-D network structure. e.g. Bakelite.

 

3. Classification based upon molecular forces

Application of polymers also depends upon their mechanical properties like tensile strength, elasticity & toughness etc. These properties depends upon Intermolecular forces like Vanderwaal forces, H-Bounds & dipole-dipole Interactions.

• Elastomers:- Polymers having weakest Intermolecular forces of attraction b/w the polymer chains. They have weak Vander waal forces so have high degree of Elasticity & can be stretched. e.g. SBR or Buna-S.
• Fibers:-Polymers having strongest intermolecular forces of attractions. They have H-Bond so have high tensile strength, high M.P. But they have very low elasticity and solubility.
• Thermoplastics:- Polymers having intermolecular forces of attraction in between of elastomers and fibers. They are hard at room temperature but soft on heating so can be remoulded. e.g. Nylon 6, Nylon 6, 6 etc.
• Thermosetting:- They are semi fluid substances with low molecular masses which when heated in a mould, undergoes a permanent change, to give a hard Insoluble mass. This is due to the Excessive cross-linking on heating. e.g.Bakelite.