Effects of Urea, Borax and Ammonium Chloride on Flame Retarding Properties of Cellulosic Ceiling Board

摘要

This work involves the impregnation of urea, borax and ammonium chloride solutions prepared in varying concentrations into strips of cellulosic ceiling board. A formulated solution was also made of equal concentration of urea and borax solution and impregnated into strips of cellulosic ceiling board. The treated and blank samples were dried and investigated for ignitability, flame propagation and afterglow time. Urea was found to give a good effect for ignitability after 28.00sec than borax, ammonium chloride and blank after 26.00sec, 25.00sec and 16.80sec respectively. Urea gave a better effect for flame propagation of 0.13x10-2cm/sec than borax, ammonium chloride and blank which has 0.24x10-2cm/sec, 0.28x10-2cm/sec and 1.95x10-2cm/sec respectively and also urea has afterglow time of 0.22x102sec than borax (0.60 x102sec), ammonium chloride (0.70x102sec) and blank (2.25 x102sec). The formulated solution drastically improved the ignitability from 16.80sec (blank) to 34.00sec and zero flame propagation and afterglow time was recorded. With this result, urea was found to give a better retarding effect, hence could be incorporated in cellulosic ceiling board during production. Keywords: Urea, borax, ceiling board, ignitability, flame propagation, afterglow time.