ZINC BORATE COMPLEX AS FLAME-RETARDANT FILLER

Water-insoluble complexes have been prepared by reaction of boric acid, pentaerythritol, and metal salts i.e., acetates of zinc, cadmium, mercury, copper, nickel, cobalt, and manganese. The composition of these complexes has been established by determining metal content and by elemental analysis, and structural aspects have been studied by far-IR spectra. The heat-resistance data indicate that the zinc-borate complex is better than other metal-borate complexes, and, therefore, it has been selected for detailed study. The effect of 10-60 parts of zinc-borate complex on novel unsaturated polyester-7 (II) in respect of gel time, exotherm peak temperature, tensile strength, % elongation, nitroglycerine absorption, and flame retardance has been studied, and results have been discussed. Further, the zinc-borate complex also gives a synergistic effect in combination with antimony trioxide similar to other metal oxide fillers.