Flame-retardant and windproof wadding and preparation method thereof

A flame-retardant and windproof wadding, characterized in that, the wadding has a sandwich structure of double mixed layers, and the sandwich structure consists of two mixed fiber layers and a polymer containing an imide ring as a base material between the two mixed fiber layers,

• wherein each of the two mixed fiber layers comprises one or more fibers selected from flame-retardant viscose fiber, flame-retardant polyester fiber, flame-retardant polyester hollow fiber and a composite fiber with a sheath-core structure having a melting point of 110-180° C. of a sheath of the sheath-core structure and a melting point of 250-260° C. of a core of the sheath-core structure,
• the polymer containing an imide ring is polyimide fiber,
• in parts by weight, the polyimide fiber is 12-28 parts, and the one or more fibers are 38-66 parts, and
• the flame-retardant viscose fiber is organic flame-retardant viscose fiber or inorganic flame-retardant viscose fiber;
• the limiting oxygen index of the flame-retardant polyester fiber and the flame-retardant polyester hollow fiber is 26-34.