The aim of this project is to develop superabsorbents from proteins in our case it is azygomycetes fungus, where the process of this fungus is studied experimentally in Universityof Borås. As a result of this experiment by-products of protein are produced and this project isabout the study to make use of such proteins as superabsorbing materials.The water absorbing capacity is computationally studied using Gibbs ensemble Monte Carlo(GEMC) simulations to determine the absorbing properties and to effectively improve theabsorbing capacity by using specific treatments, where this project focuses in using mesoscaleforce fields such as the MARTINI force field instead of atomistic force fields which wereused in studying the structure of the superabsorbents.For this purpose, the program code GEMMS is modified to make it read the desirable fileformats in order to perform the simulations. C++ is used here to code the program to read theGROMACS topology file (.top) for MARTINI force field instead of, as currently reading theatom type file (.atp) and the residue type file (.rtp) for the AMBER99 atomistic force field.

The search for cellulosic based products as a viable alternative for petroleum-based products was the impetus for covalently crosslinking lignocellulosic fibers and nanocellulose whiskers with poly(methyl vinyl ether) co maleic acid (PMVEMA) - polyethylene glycol (PEG). The lignocellulosics used were ECF bleached softwood (pine) and ECF bleached birch kraft pulp. This thesis also tests the hypothesis that water absorption and retention can be improved by grafting PMVEMA-PEG to the surface of ECF bleached kraft pulp hardwood and softwood fibers via microwave initiated crosslinking. The crosslinking of the PMVEMA to hardwood and softwood kraft ECF bleached pulp fibers resulted in enhanced water absorbing pulp fibers where the PMVEMA is grafted onto the surface of the fibers. The crosslinking was initiated both thermally and via microwave irradiation and the water absorption and water retention was measured as the percent of grafted PMVEMA. This was the first application of microwave crosslinking of pulp fibers with the goal of creating water absorbing pulp fibers. Ultimately, the water absorption values ranged from 28.70 g water per g dry crosslinked pulp fiber (g/g) to 230.10 g/g and the water retention values ranged from 26% to 71% of the water retained that was absorbed by the crosslinked pulp fibers. The microwave initiated crosslinked fibers had comparable results to the thermally crosslinked fibers with a decreased reaction time, from 6.50 min (thermal) to 1 min 45 sec (microwave). Cellulose nanowhiskers, crystalline rods of cellulose, have been investigated due to their unique properties, such as nanoscale dimensions, low density, high surface area, mechanical strength, and surface morphology and available surface chemistry. Prior to this study, the crosslinking of cellulose whiskers with the matrix via solution casting of liquid suspensions of whiskers and matrix had not been explored. The hypothesis to be investigated was that incorporating cellulosic whiskers with the PMVEMA-PEG matrix and crosslinking the whiskers with the matrix would yield films that demonstrate unique properties when compared to prior work of crosslinking of PMVEMA-PEG to macroscopic ECF bleached kraft pulp fibers. Solution cast composites of cellulose nanowhiskers-PMVEMA-PEG were crosslinked at 135 °C for 6.5 min and analyzed for crosslinking, thermal stability, strength and mechanical properties, whisker dispersion, and water absorption and uptake rates. The whisker-composites demonstrated unique properties upon crosslinking the whiskers with PMVEMA-PEG, especially the elongation at break and tensile strength upon conditioning of the final materials at various relative humidities. In addition, the whiskers improved the thermal stability of the PMVEMA-PEG matrix. This is significant as methods of improving processing thermal stability are key to developing new materials that utilize cellulose whiskers, PMVEMA, and PEG. This thesis addresses the hypothesis that cellulose nanowhiskers that are crosslinked with a matrix can create new whisker-matrix composites that behave differently after crosslinking.

This diploma thesis is focused on development and characterization of synthetic hydrogel materials containing humic acids. Based on the literature review, procedure for the preparation of synthetic superabsorbent containing humic acids was designed and optimized in order to maintain required functionality of the resulting materials, such as swelling abilities and to the controlled the release of humic substances. Very important part of this work was also characterization of superabsorbents by wide range of routine physic-chemical methods (rheometry, moisture analyzers, FT-IR). Preparation of these materials is aimed to their use in agriculture and in the environment.

No description available.

This thesis is focused on the study of the biological activity of superabsorbent polymers for environmental and agricultural applications. Generally these hydrogels perform many functions in the soil, which is increasingly stressed by treatment with synthetic fertilizers and thus loses their natural properties, such as the uptake of moisture. Addressing these issues is now in superabsorbent polymers that can absorb and also retain a lot of water around the root system as long as possible. They can perform the function of carriers gradual release fertilizer. Based on the literature review was designed and conducted the study of biological activity in the soil model on corn sown. SAPs were prepared in the framework of contract research Faculty of Chemistry of the Technical University in Brno with the company Amagro Ltd. The content of the experiment, the superabsorbent polymer, observing effects on the growth of dent corn. He was also studied root system for absorption of nutrients. Further changes were observed rheological properties of prepared superabsorbent polymer, superabsorbent polymers since they provide a source of nutrients and help to retain moisture in the soil, it is necessary to know their viskoelstick properties even at temperatures below freezing. This work is based primarily on the use of great motivation superabsorbent polymers in agriculture and also in environmental protection.