Abstract: A method for preparing substantially pure optionally substituted diaryl alkylphosphonates from an optionally substituted triarylphosphite and an optionally substituted trialkylphosphite or an optionally substituted alkanol under special reaction conditions is described.

Abstract: A method of making optionally substituted diaryl alkylphosphonates from an optionally substituted arylol, an optionally substituted alkanol, and a phosphorous trihalide is described.

Abstract: Disclosed are crystalline polyphosphonates and a method to induce crystallization. These crystalline polyphosphonates exhibit a unique and advantageous combination of properties, allowing for solid state post polymerization reactions and solid state dry mixing with other polymers. Also disclosed are polymer compositions that comprise these polyphosphonates and at least one other polymer, wherein the resulting polymer compositions exhibit flame retardant properties. Further disclosed are articles of manufacture produced from these crystalline polyphosphonates and polymer compositions, such as fibers, films, coated substrates, moldings, foams, fiber-reinforced articles, or any combination thereof.

Abstract: Disclosed are compositions including engineering plastics; melamine, melamine, melamine salts or melamine derivatives; and linear or branched polyphosphonates or copolyphosphonates which exhibit excellent processing characteristics, thermal and mechanical properties and flame resistance, and articles of manufacture produced from these materials, such as fibers, films, coated substrates, moldings, foams, fiber-reinforced articles, or any combination thereof.

Abstract: Insoluble polyphosphonates produced via a transesterification process, methods for preparing such insoluble polyphosphonates and polymer compositions and articles of manufacture including such insoluble polyphosphonates are described herein.