The flame retardance of a composite system consisting of ammonium polyphosphate (APP), pentaerythritol (PER) and melamine (MEL) used for polystyrene (PS) was studied with orthogonal design method.

CONCLUSION Chitosan-tripolyphosphate sodium polyelectrolyte could be used as a good matrix material for preparing pellets.

Taking corn starches as raw material, sodium tripolyphosphate as esterifying agent and carbamide as catalyst, high-viscosity phosphate starch is prepared by semidry process.