Hydrogels belong to the group of three-dimensional polymer materials that can swell or shrink. Their subgroups include temperature-responsive hydrogels, which change in response to temperature, reflected in their mechanical properties (shear modulus, cross-linking density, network size) and flow properties (viscosity and critical stress). In my thesis, I studied the mechanism of thermoresponsive hydrogels (TRH) based on poly(N-isopropylacrylamide) (PNIPAm) in detail. I focused on the rheological characterization of the mechanical properties of PNIPAm as a function of temperature. I prepared the samples using batch polymerization of NIPAm, varying the concentration of the polymer and the initiator, N,N,N',N'-tetramethylethylenediamine (TEMED), which led to the preparation of temperature-responsive hydrogels with the desired properties. Rheological measurements showed that both the amount of TEMED and the concentration of PNIPAm affect the structure, mechanical, and flow properties of the hydrogel.
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