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The miscibility behavior and physico-mechanical properties between methyl cellulose (MC) of different molecular weights (4 × 10(4) and 8.3 × 10(4)g/mol) and poly(acrylic acid) (PAA) were studied by viscometry, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), tensile strength and scanning electron microscopy (SEM) using water as a solvent. Various formulations were designed to investigate the effects of process variables such as pH on the physico-mechanical and miscibility properties of MC/PAA blends. The rheological features for the obtained blends are strongly dependent on the molecular weight of the MC used and pH. The viscosity measurements showed that all blends have non-Newtonian shear thinning (pseudoplastic) behavior. These blends have a single glass transition indicating that these blends are able to form a miscible phase due to the formation of hydrogen bonds between the hydroxyl group of MC and the carboxyl group of PAA. The MC/PAA blends exhibit good mechanical properties, thermal stability, characteristics of a MC-PAA polymer network. SEM of the blends showed no phase separation, when compared with the pure MC and PAA.

a b s t r a c tNovel redox-and glucose-responsive hydrogels have been synthesized by simple mixing of poly(vinyl alcohol) (PVA) and 4-mercaptophenylboronic acid (MPBA) in aqueous solutions (pH > 9) in an oxidative aqueous media. These hydrogels are produced through the formation of disulfide linkages between MPBA molecules in an oxidative environment (oxygen dissolved in solution or hydrogen peroxide added to the reaction mixture) and complexation via dynamic covalent bonds between PVA and MPBA dimer. These hydrogels show degradation in solutions of L-glutathione and D-glucose.

Abstract. In this work, hydrogels based on carboxymethylcellulose (CMC) and polyvinyl alcohol (PVA) by the method of radiation crosslinking were obtained. The presence of absorption bands of hydroxyl, simple ether and carbonyl groups in the hydrogel compositions by FTIR spectroscopy method was revealed. Also, the presence of both components CMC and PVA in hydrogel composits was proved. The kinetics of swelling of composite materials based on CMC/PVA with different volumetric ratios was studied. The influence of absorbed dose on the degree of swelling and gel contents was determined. Also, in this work the morphology of hydrogels by scanning electron microscopy (SEM) were studied. Also, optimum conditions the рossibility of use as a drug carrier have been defined. Technological scheme of the obtained composite materials based on CMC/PVA was development.

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