Chlorinated polyvinyl chloride resin and preparation method thereof

The invention discloses a chlorinated polyvinyl chloride resin and a preparation method thereof. The preparation method comprises the following steps: a step of suspension preparation and PVC (Polyvinyl Chloride) resin infiltration, a chlorination process step, a deacidification step, a neutralization step, a centrifugation step and a drying step, wherein the chlorination process step is in an anaerobic atmosphere; chlorine is introduced into the chlorination process step according to a chlorination program; and a chlorine introduction manner is to introduce liquid chlorine into the bottom ofa chlorination kettle. The chlorine content of the prepared product chlorinated polyvinyl chloride resin reaches 66-72%, the tensile strength is more than or equal to 50MPa, the Vicat softening temperature is more than or equal to 120 DEG C, and the dynamic thermal stabilization time is more than or equal to 25 minutes. Compared with the prior art, the chlorinated polyvinyl chloride resin disclosed by the invention has th