Comment on:
(a) PVC is a hard plastic but polyethylene is soft wax-like.
(b) Addition of sulphur to nutural rubber improves its properties.
(c) Polypropylene is preferred ever polyethylene.
(a) Dipole: Dipole interaction in PVC is absent.
(b) Sulphur develops cross-linking.
(c) Polypropylene is harder and stronger than polyethylene.
