Continuous fiber reinforced thermoplastic resin composite material and method for producing same
Disclosed is a scheme whereby a continuous fiber reinforced thermoplastic resin composite material applicable to production of a reinforcing material of various thermoplastic injection products and manufacture of a fiber reinforced thermoplastic plastic part using 3D printing can be produced by a simple method to have an excellent mechanical property. The present invention provides a continuous fiber reinforced thermoplastic composite material in which a plurality of yarns or tape intermediate materials are combined together to form a rod shape, and a method for producing the same.
1 . A method for producing a continuous fiber reinforced thermoplastic resin composite material, the method comprising the steps of:
(a) continuously introducing a plurality of yarn intermediate materials having a diameter of 1-3 mm into a heating unit;
(b) heating the intermediate materials to a temperature equal to or higher than the melting point of a thermoplastic resin contained in the intermediate materials to melt at least a portion of the thermoplastic resin on the surface of the intermediate material; and
(c) passing at least two of the molten intermediate materials through a nozzle to be combined together to form a rod shape,
wherein the composite material has a porosity of 1-10 vol %, and
wherein the composite material satisfies Expression 1 below on the basis of the cross-section of the composite material:
0.2 mm −1 ≤P/A≤ 5 mm −1 [Expression 1]
wherein, in Expression 1, P and A are a cross-sectional circumference length and a cross-sectional area of the composite material, respectively.
2 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 1 , wherein the intermediate material has a continuous fiber content of 30-60 wt % and a thermoplastic resin content of 40-70 wt %.
3 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 1 , wherein the heating in step (b) is performed at a temperature higher than the melting point of the thermoplastic resin by 20-40° C.
4 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 1 , wherein the nozzle has a cross-sectional shape in which a bend is not formed, or one or more recess and protrusion are formed.
5 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 1 , wherein the rod discharged through the nozzle is rotated to form a spiral shape.
6 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 1 , wherein the nozzle has an outlet and wherein the nozzle is formed in multiple stages and has a reduced diameter toward the outlet.
7 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 1 , wherein the nozzle has an inlet end and an outlet end and wherein the nozzle has a diameter ratio of the inlet end to the diameter of the outlet end of 1.5-5 and a length ratio of the outlet end to the diameter of the outlet end of 2-10.
8 . A method for producing a continuous fiber reinforced thermoplastic resin composite material, the method comprising the steps of:
(a) continuously introducing a plurality of yarn intermediate materials having a diameter of 1-3 mm into a heating unit;
(b) heating the intermediate materials to a temperature equal to or higher than the melting point of a thermoplastic resin contained in the intermediate materials to melt at least a portion of the thermoplastic resin on the surface of the intermediate material; and
(c) passing at least two of the molten intermediate materials through a nozzle having an inlet end and an outlet end and wherein the nozzle has a diameter ratio of the inlet end to the diameter of the outlet end of 1.5-5 and a length ratio of the outlet end to the diameter of the outlet end of 2-10, to be combined together to form a rod shape to produce a continuous fiber reinforced thermoplastic resin composite material,
wherein the composite material has a porosity of 1-10 vol % and satisfies Expression 1 below on the basis of the cross-section of the composite material:
0.2 mm −1 ≤P/A≤ 5 mm −1 [Expression 1]
wherein, in Expression 1, P and A are a cross-sectional circumference length and a cross-sectional area of the composite material, respectively.
9 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 8 , wherein the intermediate material has a continuous fiber content of 30-60 wt % and a thermoplastic resin content of 40-70 wt %.
10 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 8 , wherein the heating in step (b) is performed at a temperature higher than the melting point of the thermoplastic resin by 20-40° C.
11 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 8 , wherein the nozzle has a cross-sectional shape in which a bend is not formed, or one or more recess and protrusion are formed.
12 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 8 , wherein the rod discharged through the nozzle is rotated to form a spiral shape.
13 . The method for producing a continuous fiber reinforced thermoplastic resin composite material of claim 8 , wherein the nozzle has an outlet and wherein the nozzle is formed in multiple stages and has a reduced diameter toward the outlet.