Phase separation of Copolymer

- Feb 01, 2018 -

The phase separation of the block polymers occurs at a certain temperature, but the general phase separation system such as water and oil, the size of oil droplets in the micron scale, and the embedded segment of the embedded polymer link between the chemical bond, the formation of the phase structure of only dozens of to hundreds of NM, so called micro-phase separation (microphase separation). The phase transition temperature of block copolymer mainly depends on several parameters, total polymers, topological parameters (functions), and the volume fraction of a block mainly affects the entropy in the phase behavior, while the Florida-Harkin interaction coefficients between the segments affect the enthalpy. It is generally believed that when more than 10.5, the embedded polymer will occur micro-phase separation, far greater than 10.5, the phase interface becomes more steep.

As the volume fraction of the block is different, the morphology of the phase structure formed by the segmented polymer phase separation is different, there are spherical phase, six square columnar phase, layered phase and double continuous rotation-like structure, these phase structure micro-region after proper treatment, can form similar crystal lattice shape structure, thus in nanometer template, nanometer scale separation, The potential application value of catalysts and semiconductor devices. The solution of the block polymer is similar in that some segments tend to be mixed with solution, while the other is inclined to aggregate with the segments of other chains to form micelles, and various ordered phases can be formed in different concentrations.