Low-modulus polymer composition and sealant using the same

A low modulus polymer composition comprising:

• (A) at least one thermoplastic elastomer selected from the group consisting of a hydrogenated styrene-isoprene-styrene block copolymer, a hydrogenated styrene-butadiene-styrene block copolymer and a styrene-ethylene-ethylene-propylene-styrene block copolymer,
• (a) an olefin polymer,
• (B) a rubber component containing an ethylene-propylene-diene rubber, and
• (C) a paraffin oil having a pour point of not more than −35° C. as a softener,
• wherein the amount of the softener (C) is not less than 200 parts by weight based on 100 parts by weight of the total amount of the components (A), (a) and (B) and at least portion of the rubber component (B) is crosslinked by dynamic crosslinking, and wherein the hardness of said low modulus polymer composition is not less than 10 when represented by the degree of penetration of a 1/1-sized cone into the material at 23° C. and is not more than 10 when represented by Japan Industrial Standard (JIS) a Hardness.

A low modulus polymer composition comprising:

• (A) at least one thermoplastic elastomer selected from the group consisting of a hydrogenated styrene-isoprene-styrene block copolymer, a hydrogenated styrene-butadiene-styrene block copolymer and a styrene-ethylene-ethylene-propylene-styrene block copolymer,
• (a) an olefin polymer,
• (B) a rubber component containing an ethylene-propylene-diene rubber,
• (C) a paraffin oil having a pour point of point more than −35° C. as a softener, and
• (D) carbon black,
• wherein the amount of the softener (C) is not less than 200 parts by weight based on 100 parts by weight of the total amount of the components (A), (a) and (B) and at least portion of the component (B) is crosslinked by dynamic crosslinking, and wherein the hardness of said low modulus polymer composition is not less than 10 when represented by the degree of penetration of a 1/1-sized cone into the material at 23° C. and is not more than 10 when represented by Japan Industrial Standard (JIS) a Hardness.