Polyolefin-polystyrene multi-block copolymer and method for producing same
A polyolefin-polystyrene multi-block copolymer and method of making the same is disclosed herein. In some embodiments, a polyolefin-polystyrene multi-block copolymer having a ratio of a loss modulus (E″) to a storage modulus (E′) satisfying the following conditions (a) and (b) over a temperature range of −80° C. to 40° C., wherein the ratio is represented by a loss tangent (tan δ) value and is obtained by dynamic mechanical analysis (DMA), (a) a maximum of the tan δ value in a peak present in the temperature range is 0.20 to 0.35, and (b) a half-width of the peak ranges from 32.0° C. to 50.0° C. The polyolefin-polystyrene multi-block copolymer has a structure in which polystyrene chains are attached to both ends of a polyolefin chain.
1. A polyolefin-polystyrene multi-block copolymer having a ratio of a loss modulus (E″) to a storage modulus (E′) satisfying the following conditions (a) and (b) a temperature range of −80° C., 40° C., wherein the ratio is represented by a loss tangent (tan δ) value and is obtained by dynamic mechanical analysis (DMA):
(a) a maximum of the tan δ value in a peak present in the temperature range is 0.20 to 0.35; and
(b) a half-width of the peak ranges from 32.0° C. to 50.0° C.
2. The polyolefin-polystyrene multi-block copolymer of claim 1 , wherein the peak in condition (a) is one peak having the maximum at 50° C. to −30° C.
3. The polyolefin-polystyrene multi-block copolymer of claim 1 , wherein the half-width in condition (b) ranges from 32.5° C. to 49.5° C.
4. The polyolefin-polystyrene multi-block copolymer of claim 1 , further satisfying the following conditions (c) and (d):
(c) the tan δ value at −10° C. to −30° C. ranges from 0.10 to 0.30; and
(d) the tan δ value at 15° C. to 30° C. ranges from 0.05 to 0.50.
5. The polyolefin-polystyrene multi-block copolymer of claim 4 , wherein, at −10° C. to −30° C., the storage modulus E′ value thereof is 50 MPa to 200 MPa and the loss modulus E″ value is 10 MPa to 100 MPa.
6. The polyolefin-polystyrene multi-block copolymer of claim 4 , wherein, at 15° C. to 30° C., the storage modulus (E′) ranges from 10 MPa to 50 Mpa, and the loss modulus (E″) value ranges from 1 MPa to 5 MPa.
7. The polyolefin-polystyrene multi-block copolymer of claim 1 , wherein the polyolefin-polystyrene multi-block copolymer has a weight average molecular weight of 40,000 g/mol to 200,000 g/mol.
8. The polyolefin-polystyrene multi-block copolymer of claim 1 , wherein the polyolefin-polystyrene multi-block copolymer has a molecular weight distribution of 1.0 to 3.0.
9. The polyolefin-polystyrene multi-block copolymer of claim 1 , wherein the polyolefin-polystyrene multi-block copolymer is at least one selected from the group consisting of a polystyrene-poly(ethylene-co-propylene)-polystyrene block copolymer, a polystyrene-poly(ethylene-co-1-butene)-polystyrene block copolymer, a polystyrene-poly(ethylene-co-1-pentene)-polystyrene block copolymer, a polystyrene-poly(ethylene-co-1-hexene)-polystyrene block copolymer, a polystyrene-poly(ethylene-co-1-heptene)-polystyrene block copolymer, and a polystyrene-poly(ethylene-co-1-octene)-polystyrene block copolymer.