using intermittent calendering method, the poly [3,3-bis (chloromethyl) oxetane] film is uniaxially stretched 4 times at 100 ℃ to make a 20 μm thick film, then aluminum is steamed on both sides of the film, carbon is glued to the upper side as an electrode, the film is arranged in a thermostatic bath, and a DC voltage of 1000V is applied to the film through two electrodes, raise the temperature to 130 ℃, keep at this temperature for 1h, reduce the temperature to release the voltage, then connect the two electrodes to the sliding arm capacity potentiometer, raise the temperature to 110 ℃ at a speed of 1.8 ℃/min, and measure the thermal current.
Poly [3, 3-bis (chloromethyl) oxetane] was made into a 100 μm thick film by a hot press at 180 ℃. Electrodes were set on both sides of the film for polarization treatment. The polarization voltage was 500V, the polarization temperature was 90 ℃, and the polarization time was 1h.
Hot pressing poly [3, 3-bis (fluoromethyl) oxetane] at 180 ℃, I .e. immersed in water at 0 ℃, is made into mainly amorphous film. The film is extended 5 times by a 70 ℃ roller calender uniaxially to make a 80 μm thick film. The polarization condition is 5000V, the polarization temperature is 90 ℃, and the time is 1h.