A preparation method of an ion self-assembled hydroxyapatite-chitosan coated ammonium polyphosphate flame retardant
By coating hydroxyapatite and chitosan on the surface of ammonium polyphosphate using ion self-assembly technology, a dense hydrophobic core-shell structure of three-source integrated flame retardant is formed, which solves the problems of PP flammability and flame retardant performance degradation in humid environments, and achieves efficient and long-lasting flame retardant effect and improved mechanical properties.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING INST OF TECH
- Filing Date
- 2026-03-31
- Publication Date
- 2026-06-09
AI Technical Summary
Existing polypropylene (PP) materials are flammable and their flame retardant properties decrease in humid environments. Traditional flame retardants have poor dispersibility in the matrix, which affects their mechanical properties.
An ion self-assembly technique was used to perform layer-by-layer self-assembly of positive and negative ions on the surface of ammonium polyphosphate (APP), coating it with hydroxyapatite (HAP) and chitosan (CS) to form a dense, hydrophobic core-shell structure, thus constructing a three-in-one flame retardant.
It improves the dispersibility and water resistance of flame retardants in PP, forms a stable expanded char layer, and enhances the flame retardant and mechanical properties of PP, making it suitable for humid environments.
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Figure CN122167826A_ABST