Patent ID: 11891503
Assignee: INEOS STYROLUTION GROUP GMBH
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C  A | IPC A  C

Claim 0:
1. A thermoplastic elastomer composition comprising components a), b), and c):
a) 97.1 to 90.9 wt.-% of at least one star-shaped block copolymer A of the structure

[S1-(S/B)k-(S/B)l-(S/B)m-S2]n-X  (I),

where S1 and S2 are polymer blocks made from at least one vinylaromatic monomer and S/B are random copolymer blocks made from at least one vinylaromatic monomer and at least one diene forming a soft phase; X is a coupling center derived from a polyfunctional coupling agent;

b) 2.9 to 9.1 wt.-% of at least one plasticizer B; and
c) 0 to 2 wt.-% of further additives C;
wherein the sum of components a), b) and c) is 100 wt.-%;
the arms S1-(S/B)k-(S/B)l-(S/B)m-S2 are identical;
the proportion of the blocks S1 and S2 (forming a hard phase), based on the entire block copolymer A, is from 24 to 40 wt.-%;
the vinylaromatic monomer/diene (=S/B) ratio of all of the blocks (S/B) is from 1/0.45 to 1/2.5;
the S/B-ratio of the blocks (S/B)k, (S/B)l and (S/B)m is different from each other;
the S/B-ratio of the blocks (S/B)k and (S/B)m is lower than the S/B-ratio of the block(s) (S/B)l;
the weight ratio of blocks S2/S1 is from 0.1 to 0.8;
the weight average molar mass Mw of the block copolymer A is from 200,000 to 350,000 g/mol;
n is a natural number from 3 to 8;
k and m are each 1; and
l is a natural number of at least 1.