Professor. Florian J. Stadler from Shenzhen university was invited by School of Emergent Soft Matter for the seminar: The Advance of Mechanical Characterization of Soft Matter by Rheology and AFM, which communicated the recent progress of the network properties of modified N-isopropylacrylamide (NIPAM) based hydrogels characterized by Rheology and Atomic Force Microscope (AFM).

Polymer-based hydrogel possesses variety properties as similar as biological soft tissue, such as the intelligent response stimulated by environment, with a broad application in sensor, tissue engineering, etc. Prof. Stadler said “excellent biocompatible NIPAM-based hydrogels possess the similar low critical solution temperature (LCST) with human being temperature, thereby becoming a potential heat-sensitive hydrogel with the applications in drug delivery, bio-sensor, bio-sticky, etc.” Moreover, in order to adapt variety applications, chemical modified NIPAM-based hydrogel is popular in research and its properties can be characterized by Rheology and AFM.

Prof. Stadler engaged the rheology, gas sensor and photocatalysis for a long time. For instance, these fields include rheological study in polyelectrolyte, particle stabilized Pickering emulsion and sensitive hydrogel, the relation between molecular structure and nonlinear mechanical behaviors for polyolefins, and the stimulative characterization for biodegradable photocatalytic materials. He shared three achievements of his research group in this seminar. (i) Catechol and Boronic acid groups based supramolecular gels possessed excellent pH-sensitive and self-healing properties, which behaved the modulus recovery after nonlinear deformation characterized by dynamic shear rheology. (ii) The surface Young’s modulus of hydrogels were investigated by AFM and scanning electron microscope (SEM), which its homogeneous network was proved. Meanwhile, the important applications of AFM in biomedical and film technology were listed. (iii) The extensional rheological tests on NIPAM hydrogels have been conducted for determining the linear and nonlinear region of present samples, with the fitting by proper mathematic model for comprehensive information.

Prof. Stadler has similar research orientation with partial teachers of AISMST, which attract significant communication with the relevant questions being put forward.