| abstract |
The present invention provides a preparation method of a conjugated diene-based copolymer, more specifically, a preparation method of a conjugated diene-based copolymer, a conjugated diene-based copolymer prepared by the preparation method, and a method comprising the same A rubber composition of a conjugated diene-based copolymer, the preparation method comprising: (S10) p-α-methylstyrene monomer, conjugated diene-based monomer and (meth)acrylic acid hydroxyalkyl ester monomer Carry out emulsion polymerization, wherein, when the polymerization conversion rate of the emulsion polymerization is 0%, the α-methylstyrene monomer and the conjugated diene monomer are added together at one time, and when the emulsion polymerization is When the polymerization conversion rate is 0% to 80%, the hydroxyalkyl (meth)acrylate monomer is added separately in two or more times, and based on the total monomer amount, the α-methylstyrene monomer is added separately. The monomer is added in an amount of 10% by weight to 50% by weight, the conjugated diene-based monomer is added in an amount of 49% by weight to 89% by weight, and the hydroxyalkyl (meth)acrylate monomer is added in an amount of 0.1% by weight % to 5% by weight. |