Condensate of poly/mono-phosphorous acid and aluminum hydrogen phosphate, preparation and application thereof

Abstract

The present invention discloses a crystalline aluminum phosphite, preparation and an application thereof. The compound has the following structural formula (I): where, x is an integer of 1-6; n, y and p are an integer of 1-4; M is Ca, Mg, Al, Zn, Fe, Sn or Ti. The preparation method includes: after dissolving phosphorous acid and hydrogen phosphite into water, adding concentrated phosphoric acid for reaction at 80-90° C., then performing drying at low temperature, dehydration reaction at high temperature, washing and drying. The compound has very high thermal decomposition temperature, high phosphorus content, and good flame retardant property, low water absorption and low acidity; moreover, the compound can serve as a halogen-free flame retardant component of high polymer materials.

Dependencies are inferred from the claim text.