Modified polyolefin resin and dispersion composition thereof

A modified polyolefin resin, comprising a graft-modified product in which a component (A) that is a polyolefin resin is graft-modified with a component (B) that is an α,β-unsaturated carboxylic acid or a derivative thereof, and having

• a tensile modulus of 250 MPa or higher, and
• a weight-average molecular weight of 70,000 to 200,000,
• wherein the tensile modulus is a value measured with the following condition:
• the polyolefin resin or modified polyolefin resin that has been previously dried is dissolved by heating into an organic solvent;
• then, the solution thus obtained is applied onto releasing paper so as to form a film with a thickness of about 20 μm;
• after this is dried for 5 minutes with a blowing dryer whose temperature is set to 100° C., the result is kept for 24 hours under constant temperature and constant humidity conditions at 23° C. and a relative humidity of 50;
• next, this is cut to a width of 15 mm and a length of 150 mm;
• then, the releasing paper is removed to obtain a test film;
• for the test film thus obtained, the tensile modulus is measured with a tensile measurement instrument under the conditions of a pulling speed of 10 mm/minute and a distance between the chucks of 100 mm.