High melting point flame retardant crystal and method for manufacturing the same, epoxy resin composition containing the flame retardant, and prepreg and flame retardant laminate using the composition
申请人:Kishimoto Daishiro
公开号:US09371438B2
公开(公告)日:2016-06-21
Disclosed herein is a method of preparing a high-melting point flame retardant crystal, comprising the steps of: reacting 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide with 1,4-naphthoquinone in an inert solvent having a dielectric constant of 10 or less to reduce a content of by-products, thereby obtaining a reaction composition; and dissolving the reaction composition in any one solvent selected from the group consisting of ethyleneglycol, propyleneglycol, diethyleneglycol, cyclohexanone, benzyl alcohol, acetate ester, benzoate ester and a mixture thereof to recrystallize and refine the reaction composition, thereby obtaining high-melting point retardant crystal, represented by Formula 1, having a start melting point of 280° C. or more and a melting point of 291° C. or more, which are measured by differential thermogravimetric analysis.
本公开揭示了一种制备高熔点阻燃晶体的方法,包括以下步骤:在具有介电常数为10或更低的惰性溶剂中,将9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物与1,4-萘醌反应,以减少副产物的含量,从而获得反应组合物;并将反应组合物溶解在乙二醇、丙二醇、二乙二醇、环己酮、苄醇、醋酸酯、苯甲酸酯或其混合物中选择的任一溶剂中,再结晶和精制反应组合物,从而获得由Formula 1表示的高熔点阻燃晶体,其起始熔点为280°C或更高,熔点为291°C或更高,这些数值由差热重分析法测得。