Carbon fiber bundle, method for producing the same, and molded article made thereof

A method for producing a random mat, comprising the following steps:

• (1) a step in which a carbon fiber bundle is cut;
• (2) a step in which the cut carbon fiber bundle is introduced into a tube, and air is blown to the carbon fiber bundle to open the carbon fiber bundle;
• and
• (3) a step in which carbon fiber bundles opened in the step (2) are spread and simultaneously sucked, whereby the carbon fibers are dispersed, applied, and fixed,
• wherein the carbon fiber bundle comprises carbon fibers and a copolymerized polyolefin attached to a surface of the carbon fibers, the copolymerized polyolefin containing an aromatic vinyl compound and an acid, an acid anhydride, or a combination thereof as copolymerization components,
• the copolymerized polyolefin being obtainable by a graft copolymerization of (i) a member selected from the group consisting of propylene-aromatic vinyl compound copolymers, propylene-α-olefin-aromatic vinyl compound copolymers, and a combination thereof, with (ii) a member selected from the group consisting of unsaturated dicarboxylic acids, acid anhydrides thereof, and a combination thereof,
• a copolymerization ratio between the olefin and the aromatic vinyl compound in the copolymerized polyolefin being such that a molar ratio of the aromatic vinyl compound is 0.1 to 5 per 100 of the olefin,
• an amount of the copolymerized polyolefin attached being 0.01 to 10 parts by mass per 100 parts by mass of the carbon fiber bundle, and
• wherein the carbon fiber bundles are randomly oriented in a plane of the random mat.