Dispersant for carbon fibers， carbon fiber dispersion composition， and method for manufacturing carbon fiber sheet

Provided is a dispersant for carbon fibers which allows uniform dispersion of relatively long carbon fibers， e.g.， carbon fibers with a length of 12.5 mm or more， particularly 10.0-100.0 mm， more particularly 12.5-50.0 mm in an aqueous medium. A dispersant for carbon fibers used by combining: (A) a random copolymer of phenylglycidyl ether and ethylene oxide， or a random copolymer of phenylglycidyl ether， ethylene oxide and propylene oxide; and (B) a polyether-based polyurethane resin based on a bifunctional polyol and hexamethylene diisocyanate， the bifunctional polyol being polyethylene glycol and/or an ethylene oxide-propylene oxide random copolymer.

本发明提供一种碳纤维分散剂，可使较长碳纤维（例如长度不小于12.5mm的碳纤维，尤其适用于长度为10.0~100.0mm的碳纤维，更适用于长度12.5~50.0mm的碳纤维）在水介质中实现均匀分散。该碳纤维分散剂通过复配以下组分制得：(A) 苯基缩水甘油醚与环氧乙烷的无规共聚物，或苯基缩水甘油醚、环氧乙烷与环氧丙烷的无规共聚物；以及(B) 以双官能团多元醇与六亚甲基二异氰酸酯为原料制备的聚醚型聚氨酯树脂，其中所述双官能团多元醇为聚乙二醇和/或环氧乙烷-环氧丙烷无规共聚物。