Fabrication And Studies Of Stimuli-responsive Polymer Composite Film

Polymer composite films show a wide range of applications, includingantifouling biological material, chemical and biological sensors, excited light andphotovoltaic devices, optical storage and magnetic films, high charge density batteries,functional film, photolithographic coating, corrosion-resistant material, colloidalstabilization and controlled drug release devices and so on. The polymer coating layercan endow the substrate with better biocompatibility, enhanced thermal, mechanical,and chemical stability, increased wear protection, reduced friction or corrosion, aswell as modified overall physic-chemical and biological characteristics. Over theyears, the study of single-layer or multi-layer polymer composite films, particularlytheir critical application in the field of biology, has attracted widespread attention inthe scientific and practical community. Biological functional polymer films with thefunction of biological molecule immobilization, protein separation, cell adsorption,anti-bacterial or drug release have been created successfully. Although the worksinside this realm achieved many breakthroughs, due to the lack of molecular or atomiclevel information concerning the understanding of interfacial properties, preparation of strongly functional, effective, credible polymer films, in particular, which can beapplied to biological medium, remains to be challenging.In this thesis, we utilized spin-coating, physical vapor deposition and adsorptionmethods to fabricate single-layer or multi-layer polymer composite films, andcontrolled the composition of the films by altering the manipulation parameters.Besides, we studied the formation, the stimuli-responsive property and potentialapplications in biology by employing the UV-Vis, ATR-FTIR spectroscopy andmicrofluidics.In the second chapter, we prepared the P(DMAEMA-co-EGDMA)/TiO2hybridlamellar one dimensional thin film by alternatively spin-coating method. Besides, wecontrolled the optical properties of the thin film by changing the periodicity orintroducing defects intentionally. By modulating the photonic band gap positioninside the visible range of the light, we achieved full color display. And we employedthe prepared hybrid film to realize the pH-responsive detection and found out thatalteration of more than0.4unit of pH can cause the shift of the photonic band gap ofthe film distinguished by naked eyes. Based on these properties, the hybrid thin filmcan be applied to convert particular biological signal to optical signal.In the third chapter, we fabricated the Au/P(MMA-co-HEMA-co-GMA)/Ausandwich type polymer composite thin films which akin etalon structure, wecontrolled the optical properties of the thin film by changing the layer thickness andcomposition, and realized the visible detection of solvents with different polarity.Additionally, with the help of UV mask, we can also pattern the thin film andintegrate more properties.In the fourth chapter, we obtained the single-component and multi-componentpolyelectrolyte layers by adsorption in-flow. By integrating the microfluidics withATR-FTIR spectroscopy, we established the platform which can form the polymerfilm and detect the IR information in situ. The build-up platform facilitates the studyof the elements which may influence the formation of the polymer film, such asconcentration, flow rate, pH and ionic strength. Particularly, by comparison of thedynamic and static condition, we investigated the formation mechanism of the layer-by-layer film and found out that flowing indeed had great impact on theformation dynamics. Our platform paves the way for studies of in-flowadsorption ofbiologically relevant molecules, which would mimicprocesses occurring in thecardiovascular microcirculation system.In summary, we used simple and reliable method to prepare different types ofpolymer composite films. We studied the layer formation, controlled the optical andstimuli-responsive properties. It is believed that our outcomes can promote the furtherdevelopment of film materials in both theoretical and practical aspects in variousfields like chemistry and biology.