Preparation of glass reinforced NBR–phenolic composite: study of fibre length distribution and burning properties

Abstract

A glass–NBR–phenolic composite was made by combining short glass fibres and NBR–phenolic on a two-roll mill. Fibre breakage during the manufacturing process was investigated and a fibre length distribution was obtained for various mixing times. A reduction in fibre length was observed as mixing proceeds and an average fibre length was determined for different mixing times. It was concluded that for a particular matrix, the processing conditions must be optimised in order to achieve the maximum reinforcing effect of the reinforcement. Various flame retardants were employed and their effect on the burning properties of the composite was evaluated using burning rate measurements as well as sample warpage after burning. Among the flame retardants used, samples with ammonium molybdate showed the minimum warpage and the best char consistency whereas magnesium hydroxide offered the lowest burning rate.

Keywords:

• COMPOSITE
• NBR&NDASH
• PHENOLIC
• BURNING RATE
• FIBRE LENGTH
• FLAME RETARDANTS