<P> Nylon 6 fibres are tough, possessing high tensile strength, as well as elasticity and lustre . They are wrinkleproof and highly resistant to abrasion and chemicals such as acids and alkalis . The fibres can absorb up to 2.4% of water, although this lowers tensile strength . The glass transition temperature of Nylon 6 is 47 ° C . </P> <P> As a synthetic fiber, Nylon 6 is generally white but can be dyed to in a solution bath prior to production for different color results . Its tenacity is between 6 and 8.5 gm / den with a density of 1.14 gm / cc . Its melting point is at 215 ° C and can protect heat up to 150 ° C on average . </P> <P> Flavobacterium sp. (85) and Pseudomonas sp . (NK87) degrade oligomers of Nylon 6, but not polymers . Certain white rot fungal strains can also degrade Nylon 6 through oxidation . Compared to aliphatic polyesters, Nylon 6 has poor biodegradability . Strong interchain interactions from hydrogen bonds between molecular nylon chains is said to be the cause by some sources . </P> <P> At present, polyamide 6 is the most significant construction material used in many industries, for instances in automotive industry, aircraft industry, electronic and electrotechnical industry, clothing industry and medicine . Annual demand for polyamides in Europe amounts to a million tonnes . They are produced by all leading chemical companies . </P>

Name the type of condensation polymerization for the preparation of nylon 6 6