Abstract
The oxygen index (OI) is a value indicating the degree of the flammability of polymers. This paper describes an experimental study on the oxygen index of double layered materials of different kinds of fabrics. Two kind of fabric specimen are seamed each other into a double layered material by a glass fiber thread.
The oxygen index of a cotton or an acrylic fabric layered with various fabrics follows the composite law and may be calculated as follow: (OI) n= {V1/ (V1+V2) } (OI) a + {V2/ (V1+V2) } (OI) b
where, (OI) n: oxygen index of double layered fabrics,
(OI) a, (OI) b: oxygen index of single layer fabric of a, b, V1, V2: volume fraction of fabric of a, b.
The measured oxygen index of a flame retardant cotton fabric layered with a various flammable fabric is lower than the oxygen index calculated by the composite law. By contrast, the measured oxygen index of a flame retardant cotton fabric layered with a flame-proofed fabric is higher than the calculated oxygen index. Hence, the synergism effect of the flame retardant treatment is recognized.
