| abstract |
A graft copolymer (A) obtained by the graft polymerization, in the presence of 30-80 parts by mass of an ethylene-based polymer (a), of a total of 20-70 parts by mass of an aromatic vinyl-based monomer (b) and, if necessary, another vinyl-based monomer (c) copolymerizable with the aromatic vinyl-based monomer (b) ((a), (b), and (c) totaling 100 parts by mass). The graft copolymer is characterized in that the ethylene-based polymer (a) has a density of at least 0.900 g/cm 3 and less than 0.966 g/cm 3 , has a number average molecular weight of 10,000-50,000, and has a molecular weight distribution of 5-15, and in that the proportion of the ethylene-based polymer having a molecular weight of no more than 10,000 is at least 5.5%. |