Curing Kinetics Modification of Resole Type Phenolic Resin used in Preparation of Solid Fuel Projectile’s Nozzle

In the present work, novel curing solution was used to cure resole type phenolic resin which widely used in solid fuel projectile’s nozzle. Effect of para-toluene sulfonic acid as accelerator and sodium bicarbonate and urea as a retardant on curing kinetics was investigated. Curing rate of resole resin increased by increasing temperature and para-toluene sulfonic acid concentration. Curing rate of resole decreased by increasing sodium bicarbonate amount in curing solution. Curing behavior of resole resin was amazing in the presence of urea in curing solution. There was two stage at curing of resole with this novel curing solution. At the first stage resole cured partly but it flows well and at second stage resole cured completely. Sheets of chopped fiber glass impregnated with modified curing solution was prepared. Three-point bending test of these sheets shows that strength at break increased 78% and the oxyacetylene flame test showed improved thermal resistance.