Preparation method of high-temperature nylon

The invention discloses a preparation method of high-temperature nylon, which comprises the following steps: (1) carrying out water-phase polymerization reaction, namely, proportionally adding binaryacid, diamine, a reaction assistant and deionized water into a high-pressure reaction kettle to obtain a high-temperature nylon precursor; and (2) adding the high-temperature nylon precursor into a solid-phase polymerization reactor, exhausting air in the reactor, introducing an exhaust valve into water, carrying out liquid sealing, introducing inert gas, keeping the pressure in the reactor at normal pressure, raising the temperature in the reactor to 230-300 DEG C at a constant speed within a period of time, slowly reducing the vacuum in the reactor to 0-60Pa within a period of time after thereaction for a period of time, continuing the reaction for a period of time, and performing discharging to obtain the product. According to the preparation method, the high-temperature nylon precursor with specific relative v