Atudy On Reversible Addition-fragmentation Chain Transfer Polymerization And Properties Based On Cucurbit[6] Uril

In this work,through reversible addition-fragmentation chain transfer(RAFT)polymerization,cucurbit[6] urea was successfully introduced into the polymer system,and a multi-stimulus-responsive polymer containing cucurbit[6] urea was obtained.This paper is mainly divided into the following parts:(1)Prepare a star polymer with CB[6] end groups.First prepare the chain transfer reagent 2-[[(dodecylthio)thiomethyl] thio] propionic acid(DOPAT),then pass Nisopropylacrylamide(NIPAM)through the initiator 2,2-Polymerization of azobisisobutyronitrile(AIBN)to prepare macromolecular chain transfer agent polyN-isopropylacrylamide(PNIPAM),followed by cross-linking of N,Nmethylenebisacrylamide(MBA)to prepare star polymers(SSPNIPAM),and finally introduce monohydroxy CB[6] to prepare a star polymer with end group CB[6](SSPNIPAM-CB[6]).The structure of the polymer was characterized by nuclear magnetic,infrared,static light scattering,etc.,and the effect of salt,polymer molecular weight and concentration on the stimulus response performance of the polymer was studied in detail in the paper.The results show that due to the large ring of CB[6] The presence of γ causes the lowest critical temperature(LCST)of the polymer to be affected by the concentration and the addition of salt.Therefore,by controlling the content of CB[6] and the solution aggregation conditions,the stimulus response characteristics of the polymer can be adjusted.(2)Preparation of polyacrylic acid-b-polycucurbit[6] urea methacrylate block copolymer.In this thesis,the macromolecular chain transfer agent polyacrylic acid(PAA)was prepared by the reaction of acrylic acid(AA)and chain transfer agent DOPAT.Finally,the CB[6] ester was introduced to successfully prepare the polyacrylic acid based on the CB[6] PH stimuli response polymer-b-polycucurbit[6] urea methacrylate(PAA-b-PCB[6]-MA).The structure of the polymer was characterized by nuclear magnetic,infrared,static light scattering,etc.,and the effect of pH,structure,etc.on the stimulus response performance of the polymer was studied in detail in the paper.The results show that the polymer concentration,pH,and structure will affect the polymerization UCST.(3)Preparation of polycucurbit[6] urea methacrylate polymer.The CB[6] ester was directly polymerized with DOPAT through the initiator AIBN,and a stimuliresponsive polymer based on CB[6] was successfully prepared.The structure of the polymer was characterized by nuclear magnetic,infrared,static light scattering,etc.,and the stimulus response performance of the polymer was studied in detail in the paper.The results show that the polymer structure will affect the stimulus response performance of the polymer.In addition,we selected temperature-sensitive monomer N-isopropylacrylamide(NIPAM)and polyCB[6] ester for RAFT polymerization to prepare CB[6] based stimuli-responsive polymer.To study the effect of the presence of Nisopropylacrylamide on the temperature sensitivity of polyCB[6] ester.The structure characterization by GPC showed that NIPAM was successfully grafted onto polyCB[6] ester.Due to time constraints,this part of the work is still being improved.