Asphalt composition containing hydrogenated conjugated diene copolymer

• US 20050107521A1
• Filed: 10/20/2004
• Published: 05/19/2005
• Est. Priority Date: 10/21/2003
• Status: Abandoned Application

• Current Assignee: Asahi Kasei Chemicals Corporation (Asahi Kasei Corporation)
• Original Assignee: Asahi Kasei Chemicals Corporation (Asahi Kasei Corporation)
• Inventors: Shiraki, Toshinori, Sasagawa, Masahiro, Nakajima, Shigeo
• Application Number:
  US10/968,241
• Publication Number:
  US 20050107521A1
• Time in Patent Office: Days
• US Class Current: 524/571
• CPC Class Codes: C08L 2666/24 Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 53/02 of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: C08L 53/025 modified
• CPC Class Codes: C08L 95/00 Compositions of bituminous materials, e.g. asphalt, tar, pitch

Abstract

An asphalt composition comprising from 0.5 to 50 parts by weight of a hydrogenated conjugated diene copolymer (a) and 100 parts by weight of asphalt (b), wherein the hydrogenated conjugated diene copolymer (a) comprises a polymer block (A) comprising vinyl aromatic monomer units and at least one hydrogenated copolymer block (B) obtained by hydrogenation of a non-hydrogenated random copolymer block comprising conjugated diene monomer units and vinyl aromatic monomer units, the hydrogenated conjugated diene copolymer (a) having the following characteristics (1) to (5): (1) the content of the vinyl aromatic monomer units is more than 30% and not more than 60% by weight per weight of the hydrogenated conjugated diene copolymer; (2) the content of the polymer block (A) is from 5% to 50% by weight per weight of the hydrogenated copolymer; (3) the weight average molecular weight is from 30,000 to 500,000; (4) the percentage of hydrogenation of the double bonds in the conjugated diene monomer units is from 60% to 100%; and (5) at least one peak of the loss tangent (tan δ) is present in the range of from −40° C. to less than −10° C. in a dynamic viscoelastic spectrum obtained with respect to the hydrogenated copolymer.

Claims

1. An asphalt composition comprising from 0.5 to 50 parts by weight of a hydrogenated conjugated diene copolymer (a) and 100 parts by weight of asphalt (b), wherein the hydrogenated conjugated diene copolymer (a) comprises a polymer block (A) comprising vinyl aromatic monomer units and at least one hydrogenated copolymer block (B) obtained by hydrogenation of a non-hydrogenated random copolymer block comprising conjugated diene monomer units and vinyl aromatic monomer units, the hydrogenated conjugated diene copolymer (a) having the following characteristics (1) to (5):

(1) the content of the vinyl aromatic monomer units is more than 30% and not more than 60% by weight per weight of the hydrogenated conjugated diene copolymer;

(2) the content of the polymer block (A) is from 5% to 50% by weight per weight of the hydrogenated copolymer;

(3) the weight average molecular weight is from 30,000 to 500,000;

(4) the percentage of hydrogenation of the double bonds in the conjugated diene monomer units is from 60% to 100%; and

(5) at least one peak of the loss tangent (tan δ

) is present in the range of from −

40°

C. to less than −

10°

C. in a dynamic viscoelastic spectrum obtained with respect to the hydrogenated copolymer.

2. The asphalt composition according to claim 1, wherein said hydrogenated conjugated diene copolymer (a) does not substantially have a crystallization peak in the range of from −

20°

C. to S0°

C. in the chart of differential scanning calorimetry (DSC).

3. The asphalt composition according to claim 1, wherein the content of the vinyl aromatic monomer units in said hydrogenated conjugated diene copolymer (a) is more than 40% and not more than 60% by weight per weight of the hydrogenated conjugated diene copolymer (a).

4. The asphalt composition according to claim 1, wherein the hydrogenated copolymer block in said hydrogenated conjugated diene copolymer (a) is a hydrogenated copolymer block obtained by hydrogenation of a non-hydrogenated random copolymer block with a tapered structure.

5. The asphalt composition according to claim 1, wherein said hydrogenated conjugated diene copolymer (a) has at least two polymer blocks (A) comprising vinyl aromatic monomer units.

6. The asphalt composition according to claim 1, wherein the hydrogenated conjugated diene copolymer (a) has a molecular weight distribution (Mw/Mn) of from 1.1 to 5.

7. The asphalt composition according to claim 1, wherein the hydrogenated conjugated diene copolymer (a) is a modified hydrogenated copolymer to which an atomic group having a functional group is bonded.

8. The asphalt composition according to claim 1 for use in a roofing shingle.