Thermoplastic resin composition for refrigerant transportation hose and refrigerant transportation hose
A thermoplastic resin composition for a refrigerant-transporting hose includes a thermoplastic resin and an elastomer. A 10% modulus M10 (MPa) at 25° C., a water vapor permeability coefficient PC H2O (g·mm/(m 2 ·24 h) at a temperature of 60° C. and a relative humidity of 100%, a strength at break TB 150 (MPa) in a tensile test at 150° C., and an elongation at break EB 150 (%) in a tensile test at 150° C. satisfy Expressions (1), (2), and (3), namely 0.9≤M10×PC H2O ≤90 . . . (1), 1.0≤TB 150 ≤20 . . . (2), and 50≤EB 150 . . . (3).
1 . A thermoplastic resin composition for a refrigerant-transporting hose, the thermoplastic resin composition comprising:
a thermoplastic resin; and
an elastomer;
a 10% modulus M10 (MPa) at 25° C., a water vapor permeability coefficient PC H2O (g·mm/(m 2 ·24 h) at a temperature of 60° C. and a relative humidity of 100%, a strength at break TB 150 (MPa) in a tensile test at 150° C., and an elongation at break EB 150 (%) in a tensile test at 150° C. satisfying Expressions (1), (2), and (3):
0.9≤ M 10× PC H2O ≤ 90 (1)
1.0≤ TB 150 ≤ 20 (2)
50≤ EB 150 (3).
2 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 1 , wherein an elongation at break in a tensile test at a temperature of 25° C. after being left standing at 150° C. for 168 hours is 50% or more.
3 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 1 , wherein
the thermoplastic resin composition has a sea-island structure consisting of a matrix containing a thermoplastic resin and a domain containing an elastomer, and
a ratio of the elastomer in the thermoplastic resin composition is 50 mass % or more and less than 85 mass %.
4 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 1 , wherein a water vapor permeability coefficient PC H2O at a temperature of 60° C. and a relative humidity of 100% of the thermoplastic resin composition is 4.0 g·mm/(m 2 ·24 h) or less.
5 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 1 , wherein the thermoplastic resin is at least one selected from the group consisting of a polyamide resin, a polyester resin, and a vinyl alcohol resin.
6 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 1 , wherein the elastomer is at least one selected from the group consisting of a butyl rubber, a modified butyl rubber, an olefin thermoplastic elastomer, a styrene thermoplastic elastomer, a polyamide elastomer, and a polyester elastomer.
7 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 1 , wherein the thermoplastic resin composition comprises at least one processing aid selected from the group consisting of a fatty acid, a fatty acid metal salt, a fatty acid ester, and a fatty acid amide.
8 . A refrigerant-transporting hose, comprising:
an inner layer;
a reinforcing layer; and
an outer layer;
the outer layer comprising a thermoplastic resin composition according to claim 1 .
9 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 2 , wherein
the thermoplastic resin composition has a sea-island structure consisting of a matrix containing a thermoplastic resin and a domain containing an elastomer, and
a ratio of the elastomer in the thermoplastic resin composition is 50 mass % or more and less than 85 mass %.
10 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 9 , wherein a water vapor permeability coefficient PC H2O at a temperature of 60° C. and a relative humidity of 100% of the thermoplastic resin composition is 4.0 g·mm/(m 2 ·24 h) or less.
11 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 10 , wherein the thermoplastic resin is at least one selected from the group consisting of a polyamide resin, a polyester resin, and a vinyl alcohol resin.
12 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 11 , wherein the elastomer is at least one selected from the group consisting of a butyl rubber, a modified butyl rubber, an olefin thermoplastic elastomer, a styrene thermoplastic elastomer, a polyamide elastomer, and a polyester elastomer.
13 . The thermoplastic resin composition for a refrigerant-transporting hose according to claim 12 , wherein the thermoplastic resin composition comprises at least one processing aid selected from the group consisting of a fatty acid, a fatty acid metal salt, a fatty acid ester, and a fatty acid amide.
14 . A refrigerant-transporting hose, comprising:
an inner layer;
a reinforcing layer; and
an outer layer;
the outer layer comprising a thermoplastic resin composition according to claim 12 .