Fabrication And Function Of Stimuli-responsive Hyperbranched Polymers

Stimuli-responsive materials can respond to environmental changes.Stimuli-responsive materials exist widely in our life,in most metastasis processes,stimuli-responsive materials such as muscles and nerves play an important role.Hyperbranched polymers are polymerized from branched monomers,which are of highly branched and irregular topology.Hyperbranched polymers possess unique properties,such as large numbers of terminal functional groups and lower solution viscosity than linear polymers.We aim to incorporate stimuli-responsiveness into hyperbranched polymers through rational design,realizing fabrication and functionalization of stimuli-responsive hyperbranched polymers.In living organisms,the concentration of reactive oxygen species(ROS)in inflammation region is higher than that in normal regions,thus ROS-responsive materials can realize targeted drug delivery and eliminating excess ROS.Telluride possesses high ROS sensitivity,and can be employed to construct a water-soluble amphiphilic hyperbranched polymer with responsiveness to ROS in a biologically relevant concentration.A two-degree functional tellurium-containing monomer is polymerized with a three-degree functional monomer,then PEG is attached on the periphery,thus an amphiphilic tellurium-containing hyperbranched polymer is synthesized.The aggregation behavior and the ROS-responsiveness are studied.Furthermore,the mechanism of ROS-responsiveness is revealed,and through changing cross-linking degree,the responsiveness is regulated.Hyperbranched supramolecular polymers are endowed with degradability and features of traditional hyperbranched polymers.A guest-responsive hyperbranched supramolecular polymer can be fabricated through host-enhanced ?-? interaction.Three-arm monomer is designed and synthesized.It self-assembles with cucurbit[8]uril in water,spontaneously forming hyperbranched supramolecular polymers.The degree of polymerization is regulated through controlling concentration of polymerization monomers.Furthermore,the guest-responsiveness is investigated,and through gradually addition of a competing guest molecule,the degree of polymerization is regulated.Nanochannel field is developing from “double ion transport state” to “multiple ion transport state”.Multiple ion transport state can be realized by multilayer hyperbranched supramolecular polymers in nanochannel.In a single nanochannel,through layer-by-layer self-assembly method,driven by host-enhanced ?-? interaction,hyperbranched supramolecular polymerization is achieved,and multiple ion transport states are realized by the multilayer hyperbranched membrane.The nanochannel can cyclicly switched between each self-assembly state and original state.Each ion transport state can remain stable for a long time,which meets the practical needs.