Reinforced PA tensile modulus GPa

PA 66 is the oldest, the best known, the most used, with probably more than 70% of the total polyamide consumption, and is among the cheapest. 

PA 6 is technically very close to PA 66 but is far less used, perhaps about 20%. 

More expensive than commodities such as polyolefins, PVC and polystyrene brittle when dry, sensitive to water (swelling up to 10%, decrease in mechanical and electrical properties) opaque or translucent require UV and weathering protection significant shrinkage after moulding inherent flammability (but FR grades are marketed). 

They can be classified according to the type of processing, specific properties and targeted applications  

The costs, as for all plastics, fluctuate with the crude oil price, and are only given to provide an idea. They are generally of the order of a few Euros per kilogram. 

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