TECHNICAL NOTE: EFFECT OF FIRE RETARDANT TREATMENT ON MECHANICAL PROPERTIES OF MEDIUM-DENSITY COIR COMPOSITE BOARDS

Composite boards manufactured from natural fi bers such as coir can be a useful substitute for wood and plywood. They can also be chemically treated to improve its fire-resistant capabilities. To be rendered useful as a construction material, the chemical treatment has to impart fire resistance without affecting its structural properties. This article investigates the effect of fire-retardant (FR) treatment on mechanical and physical properties of medium-density coir fiberboards when treated with a waterborne solution containing boron compounds using the method of hot and cold bath treatment. Physical properties such as density, MC, and thermal conductivity were determined to compare the performance of treated samples against untreated samples. Investigation of mechanical properties such as tensile strength, bending strength, tensile modulus, and flexural modulus were also carried out using a combination of tensile, bending, and compression tests. The results obtained were encouraging, and it was observed that the coir fiberboards after FR treatment retained much of their properties and in many cases, even improved marginally.