摘要:
Block copolymers of the structure A-B-C-D of improved processability derived from a vinyl aromatic monomer and a conjugated diene, having a total bound vinyl aromatic content in the range of from 10 to 40 wt %, wherein the conjugated diene has been polymerized in a 1,2 or 3,4 addition in an amount of from 1 to 20% of the total bound conjugated diene, and wherein A represents a predominantly poly(vinylaromatic)block, B represents a predominantly poly(conjugated diene), D represents a predominantly poly(vinylaromatic)block, and C represents a tapered block of the conjugated diene occurring in the block B and a the vinyl aromatic occuring in the block D, wherein the tapering in block C shows an increasing content of vinyl aromatic monomer in the direction to block D, wherein the weight ratio of the conjugated diene occurring in block B and the conjugated diene occurring in block C is in the range of from 5:5 to 9:1, and wherein the total apparent molecular weight of which is in the range of from 130,000 to 300,000.
摘要:
Block copolymers of the structure A-B-C-D of improved processability derived from a vinyl aromatic monomer and a conjugated diene, having a total bound vinyl aromatic content in the range of from 10 to 40 wt. %, wherein the conjugated diene has been polymerized in a 1,2 or 3,4 addition in an amount of from 1 to 20% of the total bound conjugated diene, and wherein A represents a predominantly poly(vinylaromatic)block, B represents a predominantly poly(conjugated diene), D represents a predominantly poly(vinylaromatic)block, and C represents a tapered block of the conjugated diene occurring in the block B and a the vinyl aromatic occuring in the block D, wherein the tapering in block C shows an increasing content of vinyl aromatic monomer in the direction to block D, wherein the weight ratio of the conjugated diene occurring in block B and the conjugated diene occurring in block C is in the range of from 5:5 to 9:1, and wherein the total apparent molecular weight of which is in the range of from 130,000 to 300,000.
摘要:
A block copolymer composition comprising:(a) 100 parts by weight of a linear block copolymer comprising two polystyrene endblocks and one poly(conjugated diene) midblock, which block copolymer is obtained via a coupling reaction using a diglycidyloxy coupling agent and which block copolymer has a styrene content in the range of from 10 to 50% by weight based on the total weight of block copolymer and an apparent molecular weight in the range of from 100,000 to 400,000; and(b) 0.1 to 2 parts by weight of a stabilizer package consisting of:(b1) 6-(4-hydroxy-3,5-di-t-butylanilino)-2,4-bis-octylthio-1,3,5-triazine, and(b2) a tris-(nonylated phenyl) phosphite, in a weight ratio b1/b2 in the range of from 0.5 to 0.1.The block copolymer composition can be suitably applied in hot melt adhesive compositions.A process for preparing the block copolymer composition comprising the subsequent steps of preparing lithium terminated styrene-conjugated diene diblock copolymer chains, coupling these polymer chains by adding the diglycidyloxy coupling agent, adding the stabilizer package and recovering the block copolymer composition.
摘要:
A process is provided for preparing block copolymer blend compositions, which process comprises the subsequent steps of polymerizing vinyl aromatic monomer, adding conjugated diene monomer to the polymerization mixture, adding more initiator, adding of a second portion of conjugated diene monomer, adding a second portion of vinyl aromatic monomer, and adding a terminating agent. A block copolymer composition is provided having a blend of a triblock copolymer A-B-B'-A' and a diblock copolymer B'-A'.