Starch-(meth)acrylate graft coplymer oil absorbing expansion material as well as oil and water absorbing expansion material

摘要

A kind of starch-(meth)acrylate graft copolymer and its preparation method. Said copolymer is copolymerised from (meth)acrylate monomer and starch in a ratio of (0.4-8):1 by weight, the graft copolymer is grafted with one or more kinds of (meth)acrylate monomer, with the starch macromolecule as the backbone, whose degree of graft is equal or more than 70%. A kind of oil-absorbing expansion material contains the starch-(meth)acrylate graft copolymer as expansion-increasing agent. Oil and water-absorbing expansion material comprises said starch-(meth)acrylate graft copolymer, water absorbent, react monomer, surfactant and matrix. Both sealer and packer are made of said oil-absorbing expansion material as well as oil and water-absorbing expansion material.