Nylon 6 is a tough, abrasion-resistant material. It has improved surface appearance, creep resistance, and processability compared to nylon 66. It also can be molded about 80 degrees f (27 degrees c) lower with less mold shrinkage because it is slightly less crystalline. Adversely, nylon 6 has a lower modulus and absorbs moisture more rapidly than nylon 66. Moisture acts as a plasticizer, reducing tensile strength and stiffness and increasing elongation. But, while absorbed moisture reduces many properties, nylon owes part of its toughness to the plasticizing effect of moisture. As moisture content rises, significant increases occur in impact strength and general energy absorbing characteristics. Properly recognized and accounted for, the effect of moisture on the processing and properties of nylon need not be of great concern.