| abstract |
PURPOSE:To provide the structural material which is excellent in lightness of weight, strength and modulus in flexure and has the large freedom of design for shape and material by using the polyamide resin reinforced with continuous fiber and/or long fiber reinforcing material as its blank for molding. CONSTITUTION:After the reinforcing material of continuous fiber and/or long fiber has been put in a mold, while arranging it preliminarily so as to make a prescribed shape, molten omega-lactam and the like containing polymerization catalyst and initiator, is poured into the mold, and is molded into a structural material, using the monomer casting method converting it into polyamide resin by heating. Then, the fiber reinforcing material which is surface-treated with the nylon surface treating agent soluble in alcohol, water or both of alcohol and water, is used. The polyamide resin of intrinsic viscosity (eta) of 1.8 or higher contains the continuous fiber reinforcing material and/or long fiber reinforcing material of 10-80% by weight ratio. This structural material is used for the racket frame for tennis or the pole for a tent frame, etc. |