Supramolecular Hydrogen-Bonded Copolymers:Design,Synthesis And Mesomorphic Properties

Supramolecular self-assembly plays a very important role in constructing and tuning structure and properties of soft matters.Different from traditional supramolecular side-chain polymer based on binary complex system containing one polymer and one molecule,we prepared supramolecular copolymer with ternary system containing one polymer and two molecules in this work.Poly?4-vinylpridine??P4VP?,1-[4'-?3'',4'',5''-tridecyloxybenzoyloxy?phenyleneoxycarbonyl]-3-[?4-hydroxyphenyl?oxycarbonyl]benzene?12CBP?,4-hydroxyphenyl?3,4,5-tridecyloxy?benzoate?12CTB?,andredoxferrocenylderivative?FPOH?wereusedtoconstruct P4VP?12CBP?_x?12CTB?_y and P4VP?12CBP?_x?FPOH?_y.The mesomorphic properties of these two supramolecular copolymers were systematically investigated.The main topics of this paper include following aspects:The P4VP?12CBP?_x?12CTB?_y dendritic supramolecular copolymer complex system was successfully prepared via hydrogen bonding interaction?x,y denotes respectively the number of 12CBP and 12CTB per vinylpyridine repeat unit?.Despite the distinct molecular size difference between 12CBP and 12CTB,the resulting ternary supramolecular copolymers,P4VP?12CBP?_x?12CTB?_y,possess a homogeneous hexagonal columnar phase at x?0.1 and y?0.2.Each column is constructed with P4VP as the backbone tethered with mixed side chains.The column diameter is between the size of the corresponding P4VP?12CBP?_x+y and P4VP?12CTB?_x+y and could be precisely tuned from 5 to 7 nm by varying x,y and x+y.The AFM phase images show parallel aligned fingerprint-like topographies.Meanwhile,the typical hexagonal lattice patterns can be observed clearly under GISAXS.So both AFM and GISAXS prove the parallel orientation of hexagonal columnar structure in the thin film.P4VP?12CBP?_x?FPOH?_y were prepared with x+y=1,in which dendritic small molecule 12CBP with phenol hydroxyl and ferrocene derivative molecule FPOH were hydrogen-bonded to P4VP.Experimental investigations have showed that 12CBP and FPOH molecules were attached to P4VP successfully by hydrogen bond interaction and the ternary system formed a new homogeneous phase without macrophase or microphase separation.When the value of mole fraction x is between 0.1 and 0.2,the amorphous phase appears.At 0.3?x?0.5,the ternary system possesses lamellar phase structure and the size of lamellar structure decreases with the increasing x.Furthermore,the copolymers possess a homogeneous hexagonal columnar phase at 0.6?x?0.9.The hexagonal columnars'thin films after annealing show that the fingerprint-like topographies and the typical hexagonal lattice patterns in AFM and GISAXS which can be also proved that the parallel orientation of hexagonal columnar structure in the thin film.The CV results suggest that the electrochemical process of the P4VP?12CBP?_x?FPOH?_y supramolecular copolymers is a quasi-reversible process.