Preparation And Performance Study Of Intelligent Polymer Materials

In recent years, the development of intelligent polymer materials brings huge energy for the progress of human society. All kinds of stimuli-responsive polymer materials have been studied extensively. However, to drive such intelligent polymer systems, a device that can control of the external stimuli are necessary. To construct biomimetic energy transformation system generating spontaneous and periodical motion, the coupling nonlinear chemical dynamics with polymers by transferring the dissipating chemical energy of a self-oscillating reaction to the driving force for the conformation changing of the polymers were employed. Several novel intelligent polymers were prepared and the self-oscillating behaviors and the mechanisms induced by the BZ reaction were investigated in detail in this paper.Chapter 1 IntroductionThe classification, mechanisms, applications and the importance in the materials field of intelligent polymers were reviewed in this part. The characteristic of self-oscillation polymers and stimuli-responsive polymers were summarized. In addition, the prospect for development of the self-oscillation polymers was described in brief. Chapter 2 Preparation and characteristic study of poly(VF-NIPAAm-AM) gelThe vinyl ferrocene(VF), N-isopropyl acrylamide(NIPAAm) and acrylamide(AM) were used as materials to synthesis P(VF-NIPAAm-AM) multiresponsive composite hydrogel by using radical polymerization method. The chemical structures of the synthesized hydrogels were characterized by FT-IR spectroscopy and the morphologies were studied by scanning electron microscopy(SEM) method. The swelling properties were investigated at different temperature, in different pH solutions and redox media. The results showed that the prepared hydrogel with alveolate structure was very sensitive to temperature, pH value and good redox reversibility. Chapter 3 Self-oscillating soluble-insoluble changes of polymer chain induced by the BZ reaction with Fe(phen)3 catalystA novel self-oscillation was successfully synthesized by covalently bonding the Fe(phen)3 catalyst for the BZ reaction onto the poly(N-isopropylacrylamide) polymer chain. The lower critical solution temperatures(LCST) of the polymer chain in the reduced and oxidized states were 37 °C and 32 °C, respectively. The prepared polymer solution can undergo soluble-insoluble self-oscillation induced by the BZ reaction at constant temperature. Self-oscillation for the polymer solution induced by BZ reaction was studied by changing initial substrate concentrations(i.e., malonic acid, potassium bromate, and sulphuric acid) of the BZ reaction and the concentration of polymer solution. The results showed that the self-oscillation could be controlled by changing the initial substrate concentrations of polymer and potassium bromate. However, the oscillation behavior was insensitive to the concentration of malonic acid and sulphuric acid. Chapter 4 Self-oscillating soluble-insoluble changes of P(NIPAAm-co-Fe(phen)3-co-AMPS)P(NIPAAm-co-Fe(phen)3-co-AMPS) polymers with different compositions were successfully synthesized by free radical polymerization. The self-oscillating behaviors in BZ system were investigated in detail. The results indicated that the self-oscillating behaviors were observed in free acid BZ system when the content of AMPS was high. In addition, the effects of initial concentrations of BZ system were studied. It was found that the self-oscillation could be controlled by changing the initial substrate concentrations of polymer and potassium bromate. However, the oscillation behavior was insensitive to the concentration of malonic acid and sulphuric acid.