Abstract: A modified liquid diene rubber (A) has a functional group (a) derived from an acid anhydride, and satisfies all the requirements (I) to (III) below: (I) The functional group equivalent weight of the functional groups (a) is in the range of 400 to 3,500 g/eq. (II) The polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 5,000 to 20,000. (III) The melt viscosity at 38° C. is not less than 3 Pa·s and X (K) is not less than 6100 K wherein X is the slope of a linear line passing through two points in a graph in which the two points are values of melt viscosity ? (Pa·s) at 38° C. and 60° C. measured with a Brookfield viscometer which are plotted as Ln[?/(Pa·s)] on ordinate versus 1/T (K?1) on abscissa (with the proviso that T is temperature (K)).

Abstract: A modified liquid diene rubber (A) has a functional group (a) derived from an acid anhydride, and satisfies all the requirements (I) to (III) below: (I) The functional group equivalent weight of the functional groups (a) is in the range of 400 to 3,500 g/eq. (II) The polystyrene-equivalent number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 5,000 to 20,000. (III) The melt viscosity at 38° C. is not less than 3 Pa·s and X (K) is not less than 6100 K wherein X is the slope of a linear line passing through two points in a graph in which the two points are values of melt viscosity ? (Pa·s) at 38° C. and 60° C. measured with a Brookfield viscometer which are plotted as Ln[?/(Pa·s)] on ordinate versus 1/T (K?1) on abscissa (with the proviso that T is temperature (K)).