Comparison of nylons 6 and 66 in glass-filled compositions

The above comments refer to comparisons between the two compositions at the same glass-fibre level. If, however, comparison is made between a nylon 66 composition with a glass content of x% and a nylon 6 compound with a glass content of x + 5)%, then the differences in mechanical properties become very small. At the same time the nylon 6 material will have slightly easier processing characteristics and surface quality. 

Whilst nylon 66 has the higher T , the long-term heat resistance of typical copper-stabilised nylon 6 is somewhat superior in such properties as impact strength and bending strength compared to nylon 66. However, it is frequently the case that nylon 66 has better resistance to chemicals at elevated temperatures. 

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