Self-assembly Behavior Of Polymer/nanorod Composites Induced By Electric Field

Block copolymer(BCP)has always been the focus and hotspot in the field of soft matter research because of its unique structure.It is to connect several polymer chains through covalent bonds to grow chains.In particular,diblock copolymers have been found to self-assemble into various periodically ordered structures,such as layered,cylindrical,or body-centered cubic spheres.By doping(such as nanoparticles or nanorods)in the block copolymer system,or applying external fields(such as electric field or shear field,etc.),the properties of materials can be changed to better meet the needs of society and science and technology,which has become one of the research hotspots in the field of soft matter in recent years.In this paper,the self-assembly behavior of polymer nanorods under electric field induction was studied by using CDS method and Brownian dynamics method.In the first chapter,the research progress of soft matter and polymer nanosystem,the research methods and the theory of phase transition are introduced.In chapter 2,the phase formation behavior of nanorods with block copolymers and homopolymers under electric field induction and computer simulation were studied.The effects of electric field strength,wetting strength,number and length of nanorods on the self-organizing behavior of nanorods with block copolymers and homopolymers were discussed in detail.The simulation results show that when the applied electric field acts on the system and the electric field intensity acts on the infiltrating effect,the system produces the H-P structure(the hybrid structure is formed by AB/C polymer,and the nanorods are parallel arranged in the C domain and form a short end to end structure).When wetting plays a major role in the formation of the morphology of the system,disordered morphology nanorods are randomly distributed in the system,and the distribution of Ab/C is disordered.When the electric field played a dominant role,the system produced L-P morphology(the AB/C polymer formed lamellar structure,and the nanorods were arranged in parallel in the composite system).When changing the length and number of nanorods,the system changes as follows:(Si-P)?(L-P)?(H-P)?(L-D)with the increase of the number and length of nanorods.At the same time,we analyze the growth of these morphologies and structures over time.Finally,the evolution process of the orientation Angle of the nanorods with time is studied.Then,in Chapter 3,the self-assembly behavior of nanorods and three-component polymer composites under electric field induction is studied.The effects of the length of nanorods and the number of nanorods on the composite system were discussed in detail.When the nanorods are infiltrated into group C,when the nanorods are relatively short(3?L?7,10?N?100).At the same time,the number density of the nanorods is between 0.18%and 4.2%,and the mass/nanorod parallel aggregation structure is formed by self-assembly.When nano bang-bang grow larger(9?L?11),the less the number(10 ?N?50),the number density of nanorods in 0.43%?3.3%,self-assembly system happen form massive parallel aggregation structure/nanorods,continue to increase the number of bar(60?N?100),self-assembly system happen form/nanorods parallel distributed structure,block structure at this point,A/B/C polymer s ystem due to the change of the nanorods,system will support more neat.When nanorods set is relatively long(15?L?13),while the number of nanorods is small(10?N?20),the system formed block/nano self-assembly between parallel aggregation structure,continue to increase the number of bar(30?N?40),the system formed by phylogenetic self-assembled block/nanorods parallel aggregation structure into a block structure/nanorods parallel distributed structure,when the number of nanorods increase(50?N?70),self-assembly to form hybrid system happen/nanowires structure,when the nanorods(80?N?100)continue to increase the system from the assembly line without shape structure,it seems that when long long rod,by changing the number of rods,can realize the change of four phase morphology.