The invention discloses a plugging flexibilizer, comprising the components in parts by weight: 5-12 parts of
polypropylene fiber, 20-30 parts of rubber particles, 1-5 parts of high molecular
polyacrylamide, 2-8 parts of toughened nylon, 2-8 parts of
asbestos section, 5-12 parts of
plant fibers, 4-7 parts of
calcium hydroxide, and 0.1-0.4 part of polyanionic
cellulose PAC-HV. A preparation method of the plugging flexibilizer comprises the following steps: orderly adding the components in parts by weight to a kneading
machine according to a conventional preparation method at constant temperature and
constant pressure; evenly mixing and stirring; and crushing into a 0.05-1mm granular product. The plugging flexibilizer has the characteristics of being wide in material source, free of
toxicity and
pollution, simple and convenient in construction technology, good in rheological property, good in pillar-forming property, strong in tenacity, not easy to fragilely fall off, high in plugging success rate and the like, does not easily generate a rupture and a
brittle fracture in the drilling process after plugging, and is widely applied to pressure-loaded plugging
engineering of low-pressure fractured formation, large cracks, large caves, subterranean rivers and serious voidage formation in
petroleum and geological drilling.