5 to 10 wt and most preferably 3 to 10 wt based on the weight of polyester matrix powder the polyester matrix powder of the present invention contains a dispersant as component c the dispersant exhibits processing stability and functions of improved dispersibility and flowability during the processing process the dispersant may produce a free radical that combines the carbon nanotube with the dispersant suitable dispersant used in the present invention is an ethylene acrylic copolymer according to one preferred embodiment of the present invention the dispersant is ethylene acrylic acid copolymer the content of the dispersant in the present invention is 0 01 to 6 0 wt preferably 0 1 to 2 0 wt more preferably 0 2 to 1 5 wt based on the weight of polyester matrix powder in the present invention to reinforce the processing ability of the polyester fiber such as size stability thermal stability etc a chain extender as component d may be added the smaller molecular chain segment in the polymer is extended to form longer one by the combination of the unique functional group in the chain extender with the smaller molecular chain segment i e carboxyl group u2014 cooh thereby enhancing the properties of.