Abstract:
The present invention provides a method for producing a resin composition, which, by means of simple steps, can uniformly disperse microfibrillated plant fiber in a highly hydrophobic resin and can impart enhanced mechanical strength to a molding material obtained by molding the resin composition. The present invention further provides a resin composition having excellent heat resistance and low linear thermal expansion. The present invention relates to a method for producing a resin composition, the method including a step of mixing a thermoplastic resin or thermosetting resin (A), and modified plant fiber (b) or modified microfibrillated plant fiber (B), in the presence of an organic liquid (C), the modified plant fiber (b) or modified microfibrillated plant fiber (B) being obtained by modification with an alkyl or alkenyl succinic anhydride in a liquid capable of swelling microfibrillated plant fiber (B′) or plant fiber (b).