Method for preparing pH response type intelligent propping agent

The invention relates to a preparation method of a pH response type intelligent propping agent. A molecular grafting method is adopted. The method comprises propping agent surface initiation modification, grafting a response type functional polymer through a molecular grafting method, filtering and washing an obtained intermediate product, and treating under the condition of high temperature or acidification to obtain the response type intelligent propping agent. The pH response type intelligent propping agent can also be prepared by a resin coating method. According to the invention, the method starts from chemical molecule modification, and intelligent response of the propping agent is realized by grafting a functional polymer chain on the surface of the propping agent. The obtained intelligent modified propping agent has obvious pH response characteristics, and the contact angle of oil drops on the surface of the modified propping agent under the condition of low pH value is smallerthan the contact angle o