Multilayer composite

摘要

A flexibly multilayer composite comprising at least one barrier layer of high hardness TPU having a Shore D hardness of at least 80, a soft segment content of less than 5%, and a low gasoline vapor transmission rate of less than 1 g/M2/day. The composite also has at least one layer of soft TPU static dissipative polymer having a surface resistivity of less than 1.0×1012 ohms/square a Shore durometer of form 60 A to 60 D, and a gum residue of less than 20 mg per 100 ml of gasoline after 1 week exposure. The composite may have an optional third layer of an abrasion resistant TPU. The abrasion resistant TPU layer may contain reinforcement material, such as fabric.

主权项

1. A flexible multilayer composite comprising:
a) at least one layer of high hardness thermoplastic polyurethane, wherein said high hardness thermoplastic polyurethane has the following properties:
i. a Shore D durometer of at least about 80, as measured according to ASTM D-2240;ii. a soft segment content of less than about 5 weight percent; andiii. a low gasoline vapor transmission rate of less than about 1 gram/meter2/day as measured according to ASTM D-814; b) at least one layer of soft static dissipative thermoplastic polyurethane, wherein said soft static dissipative thermoplastic polyurethane has the following properties:
i. a surface resistivity of less than about 1.0×1012 ohms/square, as measured according to ASTM D-257;ii. a Shore durometer of from about 60 A to about 60 D, as measured according to ASTM D-2240;iii. a gum residue after one week exposure in gasoline of less than about 20 milligrams per 100 milliliters of gasoline, as measured according to ASTM D-381; and c) optionally, at least one layer of abrasion resistant thermoplastic polyurethane.