Characterization Of Mineralization Effectively And Photo-responsive Hyd Rogels

In recent years,hydrogel has attracted much attention because of its special three-dimensional network structure and great performance.In this paper,in-situ mineralization and photo-controlled supramolecular structure was introduced in the systems to prepare mineralized phosphate ester hydrogel,mineralized acrylic acid hydrogel and photo-responsive double network hydrogel.And the mechanical properties,stimuli-responsive and application fields of hydrogels were characterized and explored though mechanical test of mineralized hydrogels and photo-controlled tensile strain test of photo-responsive hydrogels.The contents and conclusions of this paper are exhibited as following:1.The in-situ mineralized phosphate ester hydrogel which was exhibited uniform mineraliaed degree was obtained though one-step method.Calcium phosphate particles were produced in-situ in the mineralized hydrogels though in-situ mineralization,realized the mineralization effectively and the mechanical properties of the mineralized hydrogels could be improved obviously.From these data,the maximum pressure of mineralized hydrogel could achieve to 36.58 MPa,and the compressive properties of mineralized hydrogels could be increased over 13 times during the tests.Meanwhile,the hydrogel shown the great cell compatibility and it was expected to be used as a template for osteoblasts culture and had potential application value in tissue engineering.2.The positive crosslinking agent was prepared though copolymering dopamine and positive monomer,and the three-dimensional network of hydrogels was constructed with acrylic monomers and the crosslinker.The mechanical properties of acrylic hydrogels was improved because of electrostatic interaction and calcium phosphate particles.Meanwhile,the existence of the flexible poly(acrylic acid)chain and calcium phosphate particles,the energy dissipation of mineralized acrylic hydrogels could be improved obviously.The hydrogels also could exhibite greater deformation after mineralized.In addition,the hydrogels also showed the pH responsive and excellent adhesion ability,and since the existence of positive and negative charges in the hydrogel,the hydrogel could be expected to be used as a flexible electronic device in conductive field.3.The block copolymer polyethylene oxide-b-polyacrylamide-azobenzene(PEO-b-PAAAB)was synthesized though reversible addition-fragmentation chain transfer polymer-ization(RAFT),and it was introduced as crosslinker into acrylic acid and double boednd ?-cyclodextrin systems.The double network structure of the hydrogel was attributed by supramolecular host-guest interaction of cyclodextrin and azobenzene and hydrogen bond interaction of acrylic acid and ethylene oxide.The data showed that after though UV irradiation,the fracture elongation of the hydrogel decreases from 4300%to 1200%,while the fracture stress of the hydrogel increases from 50 KPa to 95 KPa.With the change of azobenzene content in the system,the hydrogel also exhibits different tensile stress under UV irradiation,which proves that the mechanical properties of the hydrogel could be controlled though ultraviolet light.Therefore,the hydrogel has potential application value in the field of photocontrolled actuator.