Fabrics woven by spread tow yarns consisting of polymer matrix composite and method for producing the same

Abstract

A fabric woven by spread tow yarns has multiple spread tow yarns. Each one of the multiple spread tow yarns is made of matrix being thermoplastic polymer and having multiple fibers unidirectionally arranged. The fiber areal weight of each one of the multiple spread tow yarns is larger than or equal to 70 g/m2 and is less than or equal to 160 g/m2; the width of each one of the multiple spread tow yarns is less than or equal to 100 cm; and the resin content of each one of the multiple spread tow yarns is larger than or equal to 30% and is less than or equal to 50%. The widths and the fiber areal weights and the resin content of the spread tow yarns are low and are capable of providing a thin fabric woven by the spread tow yarns.

What is claimed is: 
     
         1 . A fabric woven by spread tow yarns comprising:
 multiple spread tow yarns, each one of the multiple spread tow yarns having
 a matrix being thermoplastic polymer; and 
 multiple fibers unidirectionally arranged within the matrix, wherein 
   the fiber areal weight of each one of the multiple spread tow yarns is larger than or equal to 70 g/m 2  and is less than or equal to 160 g/m 2 ;   the width of each one of the multiple spread tow yarns is thinner than or equal to 100 cm; and   the resin content of each one of the multiple spread tow yarns is larger than or equal to 30% and is less than or equal to 50%.   
     
     
         2 . The fabric woven by spread tow yarns as claimed in  claim 1 , wherein
 the fiber areal weight of each one of the multiple tow yarns is larger than or equal to 70 g/m 2  and is less than or equal to 100 g/m 2 .   
     
     
         3 . The fabric woven by spread tow yarns as claimed in  claim 1 , wherein the resin content is larger than or equal to 32% and is less than or equal to 47%. 
     
     
         4 . A method for producing the fabric woven by spread tow yarns as claimed in  claim 1  comprising:
 a tow expanding step: extending multiple tows composed of multiple fibers unidirectionally arranged through preheated spread bars to spread the multiple fibers and to expand the tows; 
 an impregnation step: impregnating the multiple tows with thermoplastic resin to form a prepreg sheet; wherein the viscosity of the thermoplastic resin is larger than or equal to 2000 cPs and is less than or equal to 30000 cPs; 
 a forming step: heating the prepreg sheet to dry the prepreg sheet and let the prepreg set; 
 a cutting step: cutting the dry prepreg sheet along the direction of the multiple fibers of each tow of the prepreg sheet and turning the prepreg sheet into multiple spread tow yarns; wherein each one of the multiple spread tow yarns is shaped as a strip; and 
 a weaving step: weaving the spread tow yarns to form a fabric and heating the fabric to accomplish the fabric woven by spread tow yarns. 
 
     
     
         5 . The method for producing the fabric woven by spread tow yarns as claimed in  claim 4 , wherein the temperature of each one of the spread bars is higher than or equal to 80° C. and is less than or equal to 120° C. 
     
     
         6 . The method for producing the fabric woven by spread tow yarns as claimed in  claim 4 , wherein an angle defined between the horizon and each one of the multiple fibers is larger than or equal to 10° and is less than or equal to 70° . 
     
     
         7 . The method for producing the fabric woven by spread tow yarns as claimed in  claim 4 , wherein multiple dry prepreg sheets with different fiber directions are laminated and compressed before being cut into multiple spread tow yarns shaped as strips in the cutting step. 
     
     
         8 . The method for producing the fabric woven by spread tow yarns as claimed in  claim 4 , wherein a heating temperature in the weaving step is higher than the glass transition temperature of the thermoplastic resin.