TABLE OF CONTENTS The nylon family of materials is becoming popular for rotational moulding due to their ease of flow and much greater strength, stiffness and toughness relative to polyethylene.
The chemical resistance and low permeability of nylon 6 make it attractive for petrol tanks, etc. It is expensive in relation to polyethylene and also absorbs moisture, which affects its dimensions. Figure 4.6 illustrates an application.
These two materials do not offer the same mechanical properties as nylon 6 but they do have better chemical resistance and lower moisture absorption.
Reactive nylons in liquid form are used commercially in rotational moulding. These have the advantage that lower mould temperatures are used (approximately 120 C). Also, there is no need for cooling because the material solidifies as a result of a chemical reaction.
