Block copolymers and composition containing the same

• US 4,987,194 A
• Filed: 09/22/1989
• Issued: 01/22/1991
• Est. Priority Date: 10/07/1988
• Status: Expired due to Term

• Current Assignee: Kuraray Company Limited
• Original Assignee: Kuraray Company Limited
• Inventors: Maeda, Miduho, Takamatsu, Hideo, Ishii, Masao, Minatono, Shobu
• Primary Examiner(s): Marquis, Melvyn I.
• Assistant Examiner(s): JAGANNATHAN, VASUDEVAN SALEM
• Application Number:
  US07/411,310
• Time in Patent Office: 487 Days
• Field of Search: 525/314, 428/462
• US Class Current: 525/314
• CPC Class Codes: C08F 297/046 polymerising vinyl aromatic monomers and isoprene, optionally with other conjugated dienes
• CPC Class Codes: C08L 53/02 of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: Y10T 428/31696 Including polyene monomers [e.g., butadiene, etc.]

Abstract

A block copolymer having a numerical average molecular weight of 30,000 to 300,000 composed of two or more blocks consisting of aromatic vinyl units having a numerical average molecular weight of 2500 to 40,000, and one or more blocks containing a vinyl bonding content of not less than 40%, having a peak temperature of primary dispersion of tan δ at least 0° C., and consisting of isoprene or isoprene-butadiene units in which at least a part of carbon-carbon double bonds may be hydrogenated, and a composition consisting of the block copolymer. The composition can provide a vibration-damping material.

Claims

1. A block copolymer having a number average molecular weight of 30,000 to 300,000 composed of at least two blocks consisting of aromatic vinyl units each having a number average molecular weight of 2,500 to 40,000 and at least one block containing a vinyl bond content of not less than 40%, having a peak temperature of primary dispersion of tan δ

of at least 0°

C., and consisting of isoprene or isoprene-butadiene units in which at least a portion of the carbon-carbon double bonds may be hydrogenated.

2. The block copolymer according to claim 1, wherein at least one of the blocks formed of isoprene or isoprene-butadiene units has a number average molecular weight of 10,000 to 200,000.

3. The block copolymer according to claim 1, wherein the proportion of blocks consisting of aromatic vinyl units range from 5 to 50% by weight of the block copolymer.

4. The block copolymer according to claim 1, wherein the sequence of blocks in the copolymer is A(BA)n or (AB)n, in which A is a block consisting of aromatic vinyl units, B is a block consisting of isoprene or isoprene-butadiene units and n is an integer of one or more.

5. The block copolymer according to claim 1, wherein the carbon-carbon double bonds in the blocks consisting of isoprene or isoprene-butadiene units are hydrogenated in amount of at least 50%.

6. A composition consisting of 100 parts by weight of a block copolymer having a number average molecular weight of 30,000 to 300,000 composed of at least two blocks consisting of aromatic vinyl units each having a number average molecular weight of 2,500 to 40,000 and at least one block containing a vinyl bond content of not less than 40%, having a peak temperature of primary dispersion of tan δ

of at least 0°

C., and consisting of isoprene or isoprene-butadiene units in which at least a portion of the carbon-carbon double bonds may be hydrogenated, and 5 to 250 parts by weight of a tackifier having a softening temperature of at least 30°

C.

7. A vibration-damping material which comprises a block copolymer having a number average molecular weight of 30,000 to 300,000 composed of at least two blocks consisting of aromatic vinyl units each having a number average molecular weight of 2,500 to 40,000, and at least one block containing a vinyl bond content of not less than 40%, having a peak temperature of primary dispersion of tan δ

of at least 0°

C., and consisting of isoprene or isoprene-butadiene units in which at least a portion of the carbon-carbon double bonds may be hydrogenated.

8. A support having a layer of a material which comprises a block copolymer having a number average molecular weight of 30,000 to 300,000 composed of at least two blocks consisting of aromatic vinyl units each having a number average molecular weight of 2,500 to 40,000, and at least one block containing a vinyl bond content of not less than 40%, having a peak temperature of primary dispersion of tan δ

of at least 0°

C., and consisting of isoprene or isoprene-butadiene units in which at least a portion of the carbon-carbon double bonds may be hydrogenated.

9. A sandwich structure which comprises two support plates and sandwiched therebetween a material which comprises a block copolymer having a number average molecular weight of 30,000 to 300,000 composed of at least two blocks consisting of aromatic vinyl units each of which has a number average molecular weight of 2,500 to 40,000 and at least one block containing a vinyl bond content of not less than 40%, having a peak temperature of primary dispersion of tan δ

of at least 0°

C., and consisting of isoprene or isoprene-butadiene units in which at least a portion of the carbon-carbon double bonds may be hydrogenated.