Impregnation of cellulose acetate films with carvacrol using supercritical carbon ioxide

Cellulose acetate films were impregnated with carvacrol using supercritical carbon dioxide. The supercritical impregnation process, conducted in a static regime at pressure of 21 MPa and temperature of 50°C, was optimized by variation in the processing time (30 and 120 min) and decompression rate (from 0.3 MPa/min to 36 MPa/min). Characterization of the obtained cellulose acetate films was performed by Atomic Force Microscopy and Differential Scanning Calorimetry. Effects of glycerol and carvacrol on the properties of the films were discussed. Release kinetics from the cellulose acetate film with 31.4% of carvacrol was investigated in a physiological saline solution. In addition, the Higuchi and Korsmeyer-Peppas release models fitted the carvacrol release curve well. Obtained cellulose acetate films impregnated with carvacrol can be of interest for the application in medicine as wound dressings considering their biocompatibility and biodegradability as well as their potential antimicrobial activity or in the food industry as an active food packaging

Jahresübersicht Flexible Fertigung

This study discusses the possibility of immobilization of colloidal TiO2 nanoparticles (NPs) onto poly(ε-caprolactone) (PCL) beads and foams that could be utilized for the removal of textile dyes from water by photodegradation. PCL foams were fabricated by environmentally friendly treatment of PCL beads in supercritical carbon dioxide. PCL beads and foams loaded with colloidal TiO2 NPs were used as photocatalysts for the removal of the textile dyes C.I. Acid Orange 7 and C.I. Basic Yellow 28 from aqueous solutions (10 mg L-1) under illumination that simulated sunlight. Unlike the PCL beads, the PCL foams provided complete discoloration of the dye solution within 24 h of illumination. The PCL foams also exhibited excellent floatability that was maintained for more than four weeks. Additionally, their photocatalytic activity was preserved within three repeated photodegradation cycles, indicating that the floating photocatalyst provided superior photocatalytic activity compared to the non-floating PCL beads.У овом раду је дискутована могућност имобилизације колоидних наночестица TiO2 на перлама или пени од поли(ε-капролактона) (PCL) које би се искористиле за уклањање боја за текстил из воде процесом фотодеградације. PCL пена је добијена еколошки прихватљивим третманом PCL перли у наткритичном CO2. PCL перле и пене су накнадно импрегниране колоидним наночестицама TiO2 и употребљене су као фотокатализатори за уклањање боја за текстил C.I. Acid Orange 7 и C.I. Basic Yellow 28 из воденог раствора (10 mg L-1) при осветљењу које симулира сунчеву светлост. За разлику од PCL перли, PCL пене су обезбедиле потпуно обезбојавање раствора боје током 24 h осветљавања. PCL пена је такође показала одличну способност плутања која је очувана дуже од четири недеље. Фотокаталитичка активност пена је задржана таком три поновљена циклуса испитивања фотодеградације што указује да овај плутајући фотокатализатор показује супериорну фотокаталитичку активност у поређењу са неплутајућим PCL перлама