Continuous-Fiber-Reinforced Resin Molding and Method for Manufacturing Same

Abstract

Provided are a continuous fiber-reinforced resin molding having high adhesion and compatibility in an interface between continuous reinforcing fibers and a synthetic resin, and in which a low occurrence of voids in the interface and adequate strength can be realized, and a method for manufacturing the same. A continuous fiber-reinforced resin molding comprising a synthetic resin and continuous reinforcing fibers having a substantially circular cross section, the continuous fiber-reinforced molding being characterized in that the number of continuous reinforcing fibers where the porosity in a peripheral-edge region separated by one tenth the radius of a single continuous reinforcing fiber from the peripheral edge part of the continuous reinforcing fibers in the interface between the synthetic resin and the single continuous reinforcing fiber in a cross section orthogonal to the length direction of the continuous reinforcing fibers is at least 10% of the total number of continuous reinforcing fibers.

1 . A continuous fiber-reinforced molded resin comprising continuous reinforcing fibers with approximately circular cross-sections and a synthetic resin, wherein at the interface between each single continuous reinforcing fiber and the synthetic resin in a cross-section perpendicular to the lengthwise direction of the continuous reinforcing fiber, the number of continuous reinforcing fibers in which the void percentage within the region of the outer peripheral edge separated from the perimeter of the continuous reinforcing fiber by 1/10 of the radius of a single continuous reinforcing fiber is 10% or lower, is at least 10% of the total number of continuous reinforcing fibers. 
     
     
         2 . The continuous fiber-reinforced molded resin according to  claim 1 , wherein the number of continuous reinforcing fibers in which the void percentage is 10% or lower is at least 90% of the total number of continuous reinforcing fibers. 
     
     
         3 . The continuous fiber-reinforced molded resin according to  claim 2 , wherein the number of continuous reinforcing fibers in which the void percentage is 1% or lower is at least 90% of the total number of continuous reinforcing fibers. 
     
     
         4 - 6 . (canceled) 
     
     
         7 . A continuous fiber-reinforced molded resin according to  claim 1 , comprising a thermoplastic resin and continuous reinforcing fibers, and having a loss tangent of 0.11 or lower in twisting mode. 
     
     
         8 . The continuous fiber-reinforced molded resin according to  claim 7 , wherein the peak temperature of the loss tangent is 78° C. or higher. 
     
     
         9 . A continuous fiber-reinforced molded resin according to  claim 1 , comprising continuous reinforcing fibers and a thermoplastic resin, and having a storage modulus of 3.4 GPa or greater in twisting mode. 
     
     
         10 . The continuous fiber-reinforced molded resin according to  claim 9 , which when cut in a diagonal direction has a storage modulus of at least 1.5 times the storage modulus when cut in a straight direction. 
     
     
         11 . The continuous fiber-reinforced molded resin according to  claim 9 , wherein the storage modulus at 150° C. is at least 25% of the maximum storage modulus. 
     
     
         12 . The continuous fiber-reinforced molded resin according to  claim 9 , wherein the shear viscosity is 330 MPa·s −1  or greater. 
     
     
         13 . A continuous fiber-reinforced molded resin according to  claim 1 , comprising continuous reinforcing fibers and a thermoplastic resin, and having a bending storage modulus of 22 GPa or greater. 
     
     
         14 . The continuous fiber-reinforced molded resin according to  claim 13 , wherein the bending storage modulus at 150° C. is at least 76% of the storage modulus at 30° C. 
     
     
         15 . The continuous fiber-reinforced molded resin according to  claim 13 , wherein the bending storage modulus retention when cut diagonally is 58% or higher. 
     
     
         16 . The continuous fiber-reinforced molded resin according to  claim 13 , wherein the tensile storage modulus at 50° C. is 22 GPa or greater. 
     
     
         17 . The continuous fiber-reinforced molded resin according to  claim 13 , wherein the maximum tensile loss tangent is 0.037 or lower. 
     
     
         18 . The continuous fiber-reinforced molded resin according to  claim 13 , wherein the temperature at which the tensile storage modulus and bending storage modulus are reversed is 95° C. or higher. 
     
     
         19 . The continuous fiber-reinforced molded resin according to  claim 13 , wherein {(tensile storage modulus−bending storage modulus) at 30° C.}/{(bending storage modulus−tensile storage modulus) at 200° C.}≥1. 
     
     
         20 . A continuous fiber-reinforced molded resin according to  claim 1 , comprising continuous reinforcing fibers with approximately circular cross-sections and two or more thermoplastic resins, wherein at the interface between a single continuous reinforcing fiber and the thermoplastic resin in a cross-section perpendicular to the lengthwise direction of the continuous reinforcing fiber, in a region of the outer peripheral edge separated from the perimeter of the continuous reinforcing fiber by 1/10 of the radius of a single continuous reinforcing fiber, the proportion of the two or more thermoplastic resins that is occupied by resin other than the resin with the highest occupying proportion of the entire resin region, is higher than the proportion occupied by the resin with the highest occupying proportion of the entire resin region, while in the resin region other than that region of the outer peripheral edge, the resin other than the resin with the highest occupying proportion of the entire resin region, of the two or more thermoplastic resins, is either evenly dispersed or mixed. 
     
     
         21 . The continuous fiber-reinforced molded resin according to  claim 20 , wherein the two or more thermoplastic resins have a sea-island structure. 
     
     
         22 . The continuous fiber-reinforced molded resin according to  claim 20 , wherein the difference between the melting point of the resin with the highest melting point and the melting point of the resin with the lowest melting point of the two or more thermoplastic resins is 100° C. or greater. 
     
     
         23 . (canceled) 
     
     
         24 . The continuous fiber-reinforced molded resin according to  claim 20 , wherein the difference between the melting peak temperature during temperature increase and the crystallization peak temperature during temperature decrease for the mixture of the two or more thermoplastic resins is smaller than the difference between the melting peak temperature during temperature increase and the crystallization peak temperature during temperature decrease for the resin with the highest occupying proportion of the entire resin region, of the two or more thermoplastic resins. 
     
     
         25 . The continuous fiber-reinforced molded resin according to  claim 20 , wherein of the two or more thermoplastic resins, the bonding strength between at least one resin other than the resin with the highest occupying proportion of the entire resin region and the continuous reinforcing fibers is larger than the bonding strength between the resin with the highest occupying proportion of the entire resin region and the continuous reinforcing fibers. 
     
     
         26 . The continuous fiber-reinforced molded resin according to  claim 20 , wherein of the two or more thermoplastic resins, the difference in surface tension between at least one resin other than the resin with the highest occupying proportion of the entire resin region and the continuous reinforcing fibers is smaller than the difference in surface tension between the resin with the highest occupying proportion of the entire resin region and the continuous reinforcing fibers. 
     
     
         27 . The continuous fiber-reinforced molded resin according to  claim 20 , wherein of the two or more thermoplastic resins, the wettability of at least one resin other than the resin with the highest occupying proportion of the entire resin region for the continuous reinforcing fibers is higher than the wettability of the resin with the highest occupying proportion of the entire resin region for the continuous reinforcing fibers. 
     
     
         28 . A method for producing a continuous fiber-reinforced resin composite material, the method comprising the following steps:
 a step of hot pressing continuous reinforcing fibers that have addition of a sizing agent comprising a coupling agent, binding agent and lubricating agent, with a thermoplastic resin having terminal functional groups that are reactive with the coupling agent, at above the melting point of the thermoplastic resin, and   a step of cooling to below the melting point of the thermoplastic resin to obtain a continuous fiber-reinforced resin composite material as a molded article.   
     
     
         29 . The method according to  claim 28 , wherein the absorption percentage of the thermoplastic resin is 0.1 wt % or greater. 
     
     
         30 . The method according to  claim 28 , wherein at least 50 wt % of the sizing agent diffuses in the thermoplastic resin during hot pressing. 
     
     
         31 . (canceled) 
     
     
         32 . The method according to  claim 28 , wherein the amount of terminal functional groups in the continuous fiber-reinforced resin composite material is less than the amount of terminal functional groups in the thermoplastic resin. 
     
     
         33 . The method according to  claim 28 , wherein the amount of terminal functional groups is 90% or less of the amount of terminal functional groups in the thermoplastic resin. 
     
     
         34 . The method according to  claim 28 , wherein the content of particulate additives in the thermoplastic resin is 30 ppm or lower. 
     
     
         35 . The method according to  claim 28 , wherein the thermoplastic resin is a polyamide resin, and the amount of carboxyl ends in the polyamide resin, as terminal functional groups that are reactive with the coupling agent, is at least 65 μmol/g. 
     
     
         36 . The method according to  claim 28 , wherein the thermoplastic resin is a polyamide resin, and the amount of amino ends in the polyamide resin, as terminal functional groups that are reactive with the coupling agent, is 40 μmol/g or lower. 
     
     
         37 . (canceled) 
     
     
         38 . (canceled) 
     
     
         39 . A method for producing a continuous fiber-reinforced molded resin according to  claim 1 , comprising a step of hot pressing reinforcing fibers and a thermoplastic resin that has a μ-drop formation coefficient with the reinforcing fibers of 10 or greater, to above the melting point of the thermoplastic resin, and a step of cooling to below the crystallization temperature of the thermoplastic resin. 
     
     
         40 . A fiber-reinforced molded resin comprising continuous reinforcing fibers according to  claim 1  made of glass and a polyamide resin, wherein when the fiber-reinforced molded resin is cut and the polished surface that has been polished with a force of 400 g/cm 2  is observed by SEM, at the interface between a single continuous reinforcing fiber made of glass and the polyamide resin in a cross-section perpendicular to the lengthwise direction of the continuous reinforcing fiber made of glass, the number of continuous reinforcing fibers made of glass in which the void percentage within the region of the outer peripheral edge separated from the perimeter of the continuous reinforcing fiber made of glass by 1/10 of the radius of a single continuous reinforcing fiber made of glass is 10% or lower, is at least 90% of the total number of continuous reinforcing fibers made of glass. 
     
     
         41 . (canceled) 
     
     
         42 . A communication device housing constituted by a composite material molded article comprising a thermoplastic resin and continuous reinforcing fibers according to  claim 1 , wherein the tensile strength satisfies the relationship specified by the following formula (3):
   Tensile strength (MPa) in lengthwise direction×0.5+tensile strength (MPa) in widthwise direction×0.5>500 MPa   Formula (3),
   
       the flexural modulus satisfies the relationship specified by the following formula (4):
   Flexural modulus (MPa) in lengthwise direction×0.5+flexural modulus (MPa) in widthwise direction×0.5>30 MPa   Formula (4),
 
 
       and the electric field shielding property measured by the KEC method is 10 dB or lower in the frequency band of 1 GHz. 
     
     
         43 . A continuous fiber-reinforced molded resin constituted by continuous reinforcing fibers and a thermoplastic resin, wherein the breaking strength due to interlayer separation is 40 MPa or higher in acoustic emission measurement.