Binding of methyl orange or ethyl orange dyes by some dioxolane copolymers: Synthesis of the copolymers and thermodynamics of the dye–copolymer interactions

Abstract

Abstract:The extent of binding of methyl orange or ethyl orange by (2-phenyl-1,3-dioxolane-4-yl) methyl methacrylate (PDMMA), 2-hydroxyethyl methacrylate (HEMA), and vinyl-pyrrolidone (VPy) copolymers has been investigated by the equilibrium dialysis method. The dialysis experiments have been carried out in a Tris (hydroxy methyl) aminomethane buffer (pH ϭ 7) and at the temperatures of 15, 25, and 35°C. The PDMMA-co-HEMA and PDMMA-coVPy copolymers have been prepared in the laboratory by using the related monomers in different ratios. The synthesized products were analyzed by Fourier Transform-infrared spectroscopy (FTIR), proton nuclear magnetic resonance ( 1 H NMR) spectroscopy, differential thermal analysis (DTA), and differential scanning calorimetry (DSC) techniques. The binding extent of the dyes by the copolymers was determined by ultraviolet (UV) absorbance measurements. The results indicate that the extent of binding is relatively higher for ethyl orange than that for methyl orange under identical conditions. The binding slightly decrease with increasing temperature, and it is accompanied with favorable free energy, and exothermic enthalpy change within the temperature range studied. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: [3355][3356][3357][3358][3359][3360][3361] 2004

Binding of Adenosine to Pendant Phenylboronate Groups of Thermoresponsive Copolymer: a Quantitative Study

“…The scheme of the reaction is given in Figure 1. To quantify adenosine binding to the boronate‐containing copolymer we applied the equilibrium dialysis technique often used for the characterisation of molecular binding to natural18 and synthetic19 polymers. Distribution of adenosine between the dialysis bag (see Experimental Part ) and the outer solution can be described by Langmuir model according to the following equations: where [B] 0 and [S] 0 are initial molar concentrations of pendent PBA groups and adenosine in the dialysis bag, respectively; [B] and [S] are equilibrium concentrations of reactive phenylboronate and adenosine, respectively; [B] i is the concentration of PBA groups unavailable for adenosine binding (non‐charged or sterically inaccessible), [BS] is the concentration of the complexes (concentration of bound adenosine), v is the volume of the dialysis bag, V is the volume of the outer solution, k is a correction coefficient, see Experimental Part .…”

Kinetic study of the thermal decomposition of (2‐phenyl‐1,3‐dioxolane‐4‐yl) methyl methacrylate and 2‐hydroxyethyl methacrylate copolymers

“…The real monomer ratios in the synthesized copolymers were determined by 1 H‐NMR and the results are given in Table I. The structural characteristics of the PDMMA copolymers are given in Figure 1 and the synthesis and characterization of the polymers are detailed in a previous report 23…”