Topological Polymers:Cyclopolymers Of Divinyl Monomers And Hyperbranched Coupling Structures

The polymer topology often determines the properties of the polymer,so the preparation of the novel topology of the polymer and its nature,both in academic researches and practical applications are of great significance.This paper mainly studies two types of polymer topology.Compared to the corresponding linear polymer,the cyclopolymer possesses particular physical and chemical properties due to the unique topological structure,for example intrinsic viscosity,solubility,glass transition temperature,optical activity and so on.These physical and chemical properties make it widely used in different areas.As the analogue to dendrimer,hyperbranched polymer(HBP)is a kind of highly branched three-dimensional spherical nano-structure polymer with many unique features such as highly branched topologies,enough space holes,multiple end functional groups,and simple synthetic methods.These characteristics distinguish them from other polymers(linear,branched and crosslinked polymers,etc.).Due to its unique physical and chemical properties,the application of HBP has been explored in various fields.The main work in this paper consists of two parts.One is the synthesis of cyclopolymers and the film formation between water and air,and the crystallization properties was studied;the other one is about the synthesis of nitrone-mediated one-dimensional bead-like hyperbranched polymer.The details are as follows:1)Synthesis of silicone-containing cyclopolymers.The desired product are obtained by esterification reaction of 1,1,3,3-tetraphenyldichlorosiloxane and hydroxyethyl methacrylate.The diene monomer was subjected to cyclization polymerization by RAFT method.The kinetic of the polymerization process and the structure of the polymer were studied by NMR,GPC and MS.The thermodynamic performance of the polymer was studied by DSC,TGA.The results showed that the cyclopolymer containing the macrocyclic structure was obtained,rather than the cross-linked product.2)Study on film formation and crystallization properties of cyclopolymers.The film formation properties of the polymer was studied by spreading the solution(with different solvents at different concentrations)on the surface of the water,and the crystallinity of the film was studied by XRD,TEM and polarizing microscope.The results showed that the cyclopolymer films have a good crystallization performance.3)Synthesis of nitro-mediated one-dimensional bead-like hyperbranched polymers.The obtained hyperbranched precursor,which obtained by ATRP method,was coupled with nitrone coupling agent,and its structure was studied by NMR,GPC.Also,the effect of the concentration of nitrone and cuprous chloride on the coupling reaction was studied.The crystal properties of the polymer solution were studied by polarizing microscope and XRD.The results show that the coupled hyperbranched polymer has the properties of lyotropic liquid crystal.