The Preparation And Performances Of Self-oscillating Gels Based On BZ Oscillating Chemical Reaction

Self-oscillating materials is a novel kind of smart polymers generating autonomous and periodical motion like living systems by the coupling nonlinear chemical dynamics with polymers,in which the dissipating chemical energy of a self-oscillating reaction transfers to the driving force for the conformation changing of the polymers.Due to the generation autonomous and stimuli-responsive activities being inherent and without any device to input external stimuli just like in a living body,this new kind of materials have important potential applications in many fields.Several self-oscillating gels based on the Belousov-Zhabtinsky(BZ)oscillating chemical reaction were prepared and the chemical structure,swelling behaviors,volume and color self-oscillating behaviors were also investigated.In addition,the prepared gels acting as the carrier of mass transportation system was also studied in brief.The thesis consists of four chapters as follows:The BZ oscillating chemical reaction and the oscillating mechanism for swelling-deswelling of self-oscillating gel were reviewed in the first chapter.The factors which affect the self-oscillating behaviors were analyzed and the development of the BZ gels was summarized.In addition,the prospect for development of the BZ gel was described in brief.In the second chapter,a self-oscillating gels were prepared by copolymerizing N-isopropylacrylamide(NIPAAm)and iron(II)(5-acrylamide-1,10-phenanthroline)bis(1,10-phenanthroline)(Fe(phen)3),which acted as the catalyst for the Belousov-Zhabotinsky(BZ)reaction.The influence of the Fe(phen)3 content on the network structure and temperature dependence of the equilibrium swelling ratio of P(NIPAAm-co-Fe(phen)3)gels was investigated.When the gel sample was immersed in the catalyst-free BZ solution,the BZ reaction occurred in the gels.The chemical wave propagation and Turing structure were observed in the gels accompanying RGB values and volume of gels self-oscillating.In the third chapter,the P(NIPAAm-co-Fe(phen)3-co-AMPS)gels with different AMPS feed ratio was successfully prepared.The chemical structure and interiormorphology were investigated by FT-IR spectroscopy analysis and SEM.It was found that the volume and color oscillated with the chemical wave propagation in the gels.The reversible changes in volume and color,the propagation chemical wave in the gels are useful in design of microfluidic devices and mass-transport systems under mild p H conditions.In the last chapter,the self-oscillating gel was composed of N-isopropylacrylamide(NIPAAm),acrylic(AA)and iron(II)(5-acrylamide-1,10-phenanthroline)bis(1,10-phenanthroline)(Fe(phen)3)as a catalyst for the BZ reaction was prepared in this chapter.A self-driven mass transportation system was constructed with a cylindrical gel placed on the surface of a sheet gel carrier.When the sheet gel was immersed in the catalyst-free BZ solution,the thickness of the gel sheet oscillated with unidirectional chemical wave propagation.Then the cylindrical gel was transported with chemical wave propagation.The cylindrical gel is transported with different rates when BZ substrate concentration or cylindrical gel cargo diameter are different.