Rubber composition and molded article manufactured therefrom

A rubber composition comprising:

• a first synthetic rubber;
• and
• a second synthetic rubber,
• wherein the first synthetic rubber is a solution-polymerized modified conjugated diene-based rubber which has a 1,2-vinyl bond content of 60 wt % to 90 wt %, and of which at least one terminal is bonded to a functional group;
• the second synthetic rubber is a conjugated diene-based rubber which has a 1,2-vinyl bond content of less than 40 wt %,
• an interaction parameter (χblend) defined by the following Mathematical Formula 1 at room temperature is 2.0×10−3 or more and 10.0×10−3 or less, wherein the interaction parameter is an interaction measurement determined according to 1,2-vinyl bond and styrene bond microstructure in the rubber composition,
• wherein the second synthetic rubber is a lithium catalyzed conjugated diene based rubber;
• wherein the second synthetic rubber is a modified conjugated diene-based rubber in which a functional group is bonded to at least one terminal;
• and
• the interaction parameter (Xblend) is defined by:
• Xblend=KφSXVS+(φS−K)φSXBS−K(φS−K)XVB [Mathematical Formula 1]
• in Mathematical Formula 1,
• K is Y−X(1−φS), φs is a volume ratio of a styrene bond in the first synthetic rubber, X is a volume ratio of a 1,2-vinyl bond in the first synthetic rubber, Y is a volume ratio of a 1,2-vinyl bond in the second synthetic rubber, XVS is 0.05650+5.65T−1, XBS is 0.00843+10.2T−1, and XVB is 0.00269+1.87T−1.