Preparation And Application Of Biomimetic Materials Based On Bidirectional Freeze Drying Methods

There is a splendid and long history that people learn from nature to design practical materials and search for applications.Toughness and lightweight materials with orderly arrangement are commonly found in nature,such as beetle elytra,pearls,animals' teeth,magnetic crystals in bacteria and human bones,and bamboo etc.These materials are usually composed of highly organized organic-inorganic materials,which distinguish characteristion are prooerties are father more excellent than their composition.Learning from nature is an effective way to design new biomimetic materials.So far,the methods to design biomimetic materials include ice template method,layer by layer self-assembly method,electrophoretic deposition method and hydrogel casting method.In this study,we reported porous and hierarchical composite materials by bidirectional freeze-dyrying methods.Meanwhile,inspired by mussel's adhesion properities,the materials have the abilities of adhesion,self-healing and regeneration properties.There materials are expected to tissue engineering,energy efficiency of buildings,flexible electronics,intelligent fabrics,etc.1.Inspired by the ordered cellular structure,we reported a kind of neural conduition scaffolds which composed of catechol-conjugated chitosan(CHI-C).In addition,the graphene oxide(GO)was added to strengthen scaffolds' properties.Then,polyethylene glycol diglycidyl ether was used to in situ crosslink to maintain the ordered porous structure.Finally,the Mouse Pheochromocytoma Cells(PC12)was used as model cells to build a cell biological model and observe the proliferation and migration of cells(PC12).2.The beetle elytra have the abilities of lightweight,high strength,high toughness and good environmental adaptability.The phenolic derivatives and amine-rich compounds in the beetle skeleton will be transported to the damage parts via under the catalysis of oxygen in the environment when the beetle elytra injured.Inspired by their structure and functions,we combined borax and pyrogallic acid(PG)to form stable complexes.Then clay nanosheets were added,followed by added Acrylamide,ammonium persulfate and N,N-methylene diacrylamide,frozon by bidirectional freeze-drying methods and in situ polymerization.And then freeze drying to obtain lamellar composite materials.Finally the materials were hydrophobic modification by chemical vapor deposition methods.In this study,we have researched the compsite materials' mechanical properties,self-healing properties and thermal insulation properties and their relationships.