Research On The Preparation And Application Of Polymer Nanotubes And Their Composite Materials

Nanotubes,as a class of nanomaterials,have attracted considerable attention due to their nanoscale tubular structures.Until now,nanotubes have been widely studied in many fields,such as drug carrier,chemical sensors,optoelectric nanodevices and so on.However,most of these studies focused on carbon nanotubes,silica nanotubes and some metal material nanotubes.Based on the properties of high plasticity,biocompatibility and surface activation of polymer materials,this paper was devoted to the preparation and application of polymer-based nanotubes and their composites.Details are as follows:(1)Fabrication of Ag/PS coaxial nanocables based on the mixed mode of soft/hard templates.Polystyrene(PS)nanotubes were firstly prepared by porous anodic aluminum oxide(AAO)hard template,and then,in order to effectively introduce silver nitrate solution into hydrophobic cavity of polystyrene(PS)nanotubes,ethylene glycol solution and Pluronic F127(F127)were used as the solvent and guiding agent,respectively.Under the synergy of the soft template of F127 and hard template of AAO,silver nanowires were formed in situ in the PS nanotubes with the help of the reduction of the PEO blocks of F127.The preparation conditions and forming mechanism of high quality Ag/PS coaxial nanocables were studied in detail.This kind of preparation strategy can be extended to the design of more metal/polymer coaxial nanocables in the future,facilitated to create complex and functional nanostructures and components.(2)Fabrication of Fe3O4@PS/PDA-Ag hybridnanotubes with size-controllable and their catalytic effects.Fe3O4@PS nanotubes were firstly prepared using polystyrene/toluene solution containing highly dispersed oleic acid modified Fe3O4 particles in AAO template.Next,the biomimetic technique was used to form in situ silver NPs on the surface of Fe3O4@PSnanotubes through dopamine coating.The prepared Fe3O4@PS/PDA-Ag hybridnanotubes were characterized using a range of analytical methods,including transmission electron microscopy,thermogravimetric analysis,UV-visible spectroscopy,and X-ray diffraction.It was found that such prepared Fe3O4@PS/PDA-Ag hybridnanotubes possessed excellent activities in catalyzing the reduction of 4-nitrophenol(4-NP)by NaBH4 in the aqueous phase.The rate constant of Fe3O4@PS/PDA-Ag hybridnanotubes was 6.55 x 10-3 s-1,and Fe3O4@PS/PDA-Ag hybridnanotubes had high catalytic activity and high recyclability performance.Furthermore,they were readily separated from fluid and retrieved by an external magnet.(3)Preparation of novel biomimetic enzymes for detecting superoxide anions based on self-assembly technique.In view of the low specific surface area in the presence of manganese phosphate nanosheets,manganese phosphate was decorated onto the surface of magnetic polymeric nanotubes by surface self-assembly processes,and used to detect superoxide anions.The Fe3O4@PS/PDA/SiO2-Mn3(PO4)2 composite nanotubes were characterized by a range of analytical methods,including transmission electron microscopy,zeta potential analyzer,fourier transform infrared spectroscopy and energy dispersive X-ray spectroscopy.Results indicated that the magnetic polymeric nanotubes that decorated by Mn3(PO4)2 nanoparticles could effectively catalyze the dismutation of O2·-that attributed to its high surface areas and a large number of active sites of self-assembled Mn3(PO4)2 nanoparticles.and the biosensor exhibited excellent analytical performance,the wide linear range from 0.15 to 3.0 μM,with good detection sensitivity,high selectivity,good stability and accuracy.This combination of nanotechnology and self-assembly technology provides a new platform for the design and manufacture of high-performance electrochemical sensors.(4)Electrochemical immunosensor based on magnetic polystyrene nanotubes-gold nanoparticles for detection of alpha-fetoprotein.Based on the porous alumina template method and the surface modification technique,magnetic PS hybrid nanotubes were firstly prepared.And then preparation of poly(dopamine)coated magnetic PS hybrid nanotubes by biomimetic technique.Based on the reduction of poly(dopamine),the gold nanoparticles were obtained by in situ reduction on the surface of Fe3O4@PS/PDA hybrid nanotubes.The prepared Fe3O4@PS/PDA-Ag hybridnanotubes were used to construct an immunosensor to detect alpha-fetoprotein,and Fe3O4@PS/PDA-Ag hybridnanotubes were characterized using a range of analytical methods,including transmission electron microscopy,thermogravimetric analysis,UV-visible spectroscopy,and X-ray diffraction.The results of electrochemical experiments showed that the detection range of immunoassay was wide,from 0.01 to 100 ng/mL,and with high specificity,high anti-interference ability,good stability and accuracy.As a modified material,polymer nanotubes have great potential for developing biosensors with good electrochemical properties.