The Study On Linear,cyclic And Tadpole-shaped Block Copolymer Based On (2-(diethylamino)ethyl Methacrylate)

Different topologies have different properties than linear polymers.Cyclic and tadpole-shaped copolymers have different properties from linear polymers,but their extensive application researches are limited,because their complex topological structures are difficult to synthesize.Poly(N,N-diethylaminoethylmethacrylate)(PDEAEMA)has rich application prospects,such as stabilizers,nanogels,hydrogels,dental applications or intraocular lens biomaterials.The study of Cyclic and tadpole-shaped copolymers based on methacrylic acid(N,N-diethylaminoethyl ester)has not been reported in the literature.In this paper,the linear block copolymer PNVCL-b-PDEAEMA was first synthesized by atom transfer radical polymerization(ATRP)and the cyclic homopolymer c-PDEAEMA was synthesized via Cu(I)-catalyzed alkyne/azide(CuAAC)click reaction.And tadpole-shaped copolymer(c-PNVCL)-b-PDEAEMA,where the cyclic homopolymer c-PDEAEMA was synthesized at higher concentration(?20 mg/mL)was also synthesized.The three polymers synthesized above were characterized by gel permeation chromatography(GPC),nuclear magnetic resonance(~1H NMR)and infrared spectroscopy(IR).The performance shows that the LCST of the block copolymer PNVCL-b-PDEAEMA is concentration-dependent.With the increase of pH,the LCST of PNVCL-b-PDEAEMA decreases gradually,while its particle size gradually increases.Peptidomimetic drug-loaded micelles experiments were performed on the linear block copolymer PNVCL-b-PDEAEMA.Compared with the linear polymer1-PDEAEMA,the cyclic polymer c-PDEAEMA increases the CMC value,and its particle size also increases compared with its precursor.The linear polymer1-PDEAEMA and the cyclic polymer c-PDEAEMA form a gel in solution.The bundles are spherical,and the chemical shift values of the homopolymer gradually increase with increasing pH.Both the cyclic homopolymer c-PNVCL-OH and the c-PNVCL-b-PDEAEMA are concentration-dependent,and the CMC value of(c-PNVCL)-b-PDEAEMA is smaller than that of the cyclic homopolymer c-PNVCL-OH.The micelles formed by(c-PNVCL)-b-PDEAEMA in aqueous solution are irregularly spherical.As the pH increases,the LCST of the copolymer(c-PNVCL)-b-PDEAEMA gradually decreases and its particle size gradually increases.