In which classes, the polymers are classified on the basis of molecular forces?

On the basis of molecular forces,polymers are classified into following classes-
1.Elastomers- In elastomers the polymer chains are held together by the weakest intermolecular forces which allow the polymer to be stretched.For ex-vulcanised rubber.
2.Fibres- Such polymers posses high tensile strength and high modulus whuch is due to the strong intermolecular forces like hydrogen bonding.For ex- nylon-66
3.Thermoplastics- The intermolecular forces in these are intermediary to those of elastomers and fibres because of which these can be easily moulded by heating.There is no cross-linking between the chains.For ex- polyethylene,polystyrene etc.
4.Thermosetting- In such polymers there is extensive cross-linking between different polymer chains forming three-dimensilonal network of bonds connecting the polymer chains.These can be heated in a mould to become infusible and form insoluble hard mass.For ex- bakelite