Process for preparing linear block copolymer
AssigneeLG Chem, Ltd.
InventorsMoon-Seok Chun, Jae-Cheol Cho, Kyu-Seok Sim, Choon-Hwa Lee
Life of this patent
Estimating the term…
Abstract
The present invention relates to a linear block copolymer and a process for preparing the same, particularly to a linear block copolymer and a process for preparing the same which can improve transmissivity of a block copolymer and remarkably lower a Haze value by introducing a vinyl aromatic hydrocarbon to conduct primary polymerization, simultaneously introducing a vinyl aromatic hydrocarbon and a conjugated diene monomer therein to conduct secondary polymerization, and introducing a vinyl aromatic hydrocarbon therein to conduct tertiary polymerization, thereby locating a conjugated diene/vinyl aromatic hydrocarbon copolymer block in a block copolymer.
Claims9
A linear block copolymer comprising:
- a structure represented by the following Chemical Formula 1:
- A1-B1-(B/A)-A2-A3,
- wherein
- A1, A2, and A3 are each independently a vinyl aromatic hydrocarbon block, having a weight average molecular weight of 100 to 100,000;
- B1 is a conjugated diene monomer block, having a weight average molecular weight of 100 to 100,000;
- and
- (B/A) is a conjugated diene monomer/vinyl aromatic hydrocarbon copolymer block, having a weight average molecular weight of 100 to 100,000;
- wherein a weight ratio of the vinyl aromatic hydrocarbon/conjugated diene monomer in the linear block copolymer is 25:75 to 50:50.
A process for preparing a linear block copolymer represented by the following Chemical Formula 1:
- A1-B1-(B/A)-A2-A3, wherein A1, A2, and A3 are each independently a vinyl aromatic hydrocarbon block having a weight average molecular weights of 100 to 100,000;
- B1 is a conjugated diene monomer block having a weight average molecular weight of 100 to 100,000;
- and (B/A) is a conjugated diene monomer/vinyl aromatic hydrocarbon copolymer block having a weight average molecular weight of 100 to 100,000, wherein a weight ratio of the vinyl aromatic hydrocarbon to the conjugated diene monomer in the linear block copolymer is 25:75 to 50:50, comprising:
- introducing a vinyl aromatic hydrocarbon into a reactor to polymerize until at least 99% of monomers are consumed;
- simultaneously introducing a vinyl aromatic hydrocarbon and a conjugated diene into the reactor to polymerize until at least 99% of monomers are consumed;
- and
- introducing a vinyl aromatic hydrocarbon into the reactor to polymerize until at least 99% of monomers are consumed.
Dependencies are inferred from the claim text.