AROMATIC POLYSULFONE, PREPREG, AND METHOD FOR PRODUCING PREPREG

An aromatic polysulfone which is a thermoplastic aromatic polysulfone obtained by polymerizing a dihalogeno compound (A) represented by a formula (A) and a dihydric phenol (B) represented by a formula (B), wherein a value of a ratio (Mw/Mn) between a number average molecular weight (Mn) and a weight average molecular weight (Mw) is at least 1.91, and the number average molecular weight (Mn) is at least 6,000 and less than 14,000, [in the formulas (A) and (B), each of X and X' independently represents a halogen atom; each of R 1 , R 2 , R 3 and R 4 independently represents an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; each of n 1 , n 2 , n 3 and n 4 independently represents an integer of 0 to 4; and when n 1 , n 2 , n 3 or n 4 is an integer of 2 to 4, a plurality of R 1 , R 2 , R 3 or R 4 groups may be the same or different from each other.]