China Petroleum & Chemical Corporation
Gradient copolymer, its production and application thereof

Abstract:

A gradient copolymer comprises or consists of n polymer components. The n polymer components each independently represents an addition polymer of a monomer of the formula (I), ##STR00001## and/or a mixture thereof, or the n polymer components each independently comprises or consists essential of one or more structural units represented by the formula (I-1), ##STR00002## The symbol n represents an integer within the closed interval [5, .infin.]. The average side chain carbon number of the i-th polymer component as determined according to the nuclear magnetic resonance method is expressed as X.sub.i, with the symbol i representing an arbitrary integer from 1 to n, the relationship X.sub.1<X.sub.2< . . . <X.sub.n-1<X.sub.n holds.