Microstructures And Transformation Of Triblock Copolymer Films Induced By Surface Field

Block copolymers can self assemble into a series of ordered structures,such as parallel lamella and hexagonal structure.This distinguishing feature of copolymers has been widely concerned in many fields,such as biological physics,nanometer material and nanotechnology.comparing with the structures of in-bulk at the same time,both geometric confinement in enclosed space and the external environment can induce the self-assembly of copolymers into more abundant structures.So this paper intends to use the self consistent field theory to study microstructures and transformation of triblock copolymer films induced by surface field.Firstly considering the two kinds of thin film induced by surface field,which respectively are non-modified stripes and modified stripes.We can obtain a series of novel copolymers confined films by adjusting the field strength and thickness of the thin films.The microstructures show that the copolymers tend to form a regular and ordered lamellar or perforated layer confined thin films with non-modified stripes,while in the case of films with modified stripes,the copolymers tends to self assemble into horizontal structures in their respective modified stripe areas.Following apply real space self-consistent field theory to investigate microstructures and transformation of star triblock copolymer films induced by surface field.In this part we choose two kinds of composition of copolymers,which respectively is f A=f B =f C=0.1:0.4:0.5and f A=f B =f C=0.3:0.3:0.4.We can adjust the surface field strength of the thin films and thickness of the thin films regularly for summarizing microstructures and transformation of triblock copolymer.At the same time,we further change the periodic size of confined films to study the influence of the periodic adsorption region size on the self-assembly structure of the three block copolymers under certain parameters.At last,we analyze the results and obtain the phase diagram of the star three block copolymer.We wish these researches can provide some help for future theoretical and experimental research.