Preparation Of PH Responsive Polymer And Its Performance Evaluation

pH-responsive polymers have been extensively investigated and used as smart biomaterials. The phase transition or phase separation of polymer is induced by a change in various pH conditions. However, the application of polymers to numerous field is limited because most pH-responsive polymers are not biodegradable. Polymeric biodegradability and biocompatibility are the most important factors for the application of polymers. They are useful in pharmaceutical and biomedical areas. Cyclodextrin and chitosan are well-known naturally occurring polysaccharides macromolecular compound which are widely used in environmental engineering, biomedical, and food engineering areas. Chitosan and its derivatives possess excellent biodegradability, biocompatibility, and pH-responsive. Many of inorganic or organic guest molecules can be fully or partly incorporated into the cavities of CDs to form inclusion complexes because of their unique cavity of hydrophobic interior and hydrophilic exterior. The formation of inclusion complex can modify the physical and chemical properties of guest molecules such as increasing their solubility, enhancing their stability, enhancing their fluorescence intensity, and augmenting their bioavailability etc. Therefore, this paper has devoted to grafting CD molecules into chitosan in order to develop a promising polymer and extending the polymer’s used in many field.Based on the basis of reference to domestic and foreign research, this paper prepare allyl cyclodextrin (A-J3-CD) using Williamson ether reaction, and prepare Allyl carboxymethyl chitosan (A-CMCTS) using scmfi base reaction and Williamson ether reaction.By introducing the modified cyclodextrin into modified chitosan. this paper not only examines the polymer’s dissolution performance under different pH conditions but also determines the optimum condition for synthesis of the polymer by single factor experiment. On the basis of single factor experiments, this article optimizes the main factors influencing the viscosity of polymer solution using the response surface analysis method. Furthermore the structure of the polymer was characterized by IR spectra,’HNMR, SEM.The inhibition effect of the polymer has been investigated in corrosion solution using electrochemical impedance spectroscopy (EIS) techniques, potentiodynamic polarization and scanning electron microscopy (SEM). potentiodynamic polarization results showed that the polymer mainly act as cathode inhibition effect.Besides, the results of EIS and potentiodynamic polarization showed good agreement and the highest inhibition efficiency over82%was obtained, indicating that the polymer can act as a more efficient inhibitor for carbon steel. The results of SEM further showed that the polymer was a adsorption inhibitor and formed fully dense passive film on the carbon steel surface, which probably refers to the introducing functional groups of A-(3-CD that results in the formation of fully dense passive multi-film. So, based on above study results, a possible inhibition mechanism of the polymer has been proposed in this paper.In addition, this paper studied the adsorption of the polymer for2,4-dinitrophenol and phenol, and also studied the effect of adsorption temperature, solution pH value, adsorption time, initial concentration of phenol, the polymer dosage on the adsorption performance. The experimental results showed the optimal adsorption conditions as follows:the adsorption temperature30癈, the adsorption time50-60min, pH value of4.7for phenol, pH value of3.5for2,4-dinitrophenol. The adsorption capacity of the polymer to phenol and2,4-dinitrophenol was increased with enlarging the concentration of phenol and2,4-dinitrophenol. The adsorption rate of2,4-dinitrophenol and phenol would both reach to100%, while0.08g polymer,50mL of15mg/L2,4-dinitrophenol solution and0.06g polymer,50mL of15mg/L phenol solution were used, respectively. Therefore, the above experimental results showed that the polymer has a good adsorption performance for phenol and2,4-dinitrophenol in wastewater.