Fabrication And Properties Of 3D Printing Elastome And Swelling Controllable Hydrogels Based On Silicon

Because of the high bond energy and unique flexibility of Si-O,polysiloxane has high elongation and good elasticity.In addition,this material also has excellent oxygen permeability and biological activity,and has a great application prospect in biomedical fields.In this study,the polysiloxane was combined with acrylate monomer to prepare a 3D-printed elastomer and a swelling controllable hydrogel by virtue of its good properties and fast curing of photopolymerization.With the development of the society,the demand of elastomer processing is increased,especially the precision demand.As the most mature printing technology with the highest printing accuracy,the combination of UV-curing 3D printing and elastomer obviously has a huge application prospect.However,few inks are available for photocurable 3D printing elastomers.Most of the photosensitive inks reported so far are made from polymer long chains with high viscosity and require multi-step complex special process.In this project,the ultra-low viscosity photosensitive ink was firstly developed by using commercial monomer resin for photocurable 3D printing elastomer.Ultra-low viscosity photosensitive ink was prepared with methyl trimethoxysilane(MTMS)and hydroxyethyl acrylate(HEA)as the main raw materials.As a photopolymerizable monomer,HEA provided the performance of photocurable 3D printing for ink.The polymerization generated a physical cross-linked network,which enabled the sol-gel reaction of MTMS to generate polysiloxane.The main advantages of this method were that all raw materials can be directly obtained and the viscosity was ultra-low(10 mPa·s).The printed elastomer had self-healing properties and the mechanical properties of the printed elastomer had reached the average level of the reported 3D printed elastomer.Hydrogel is a three-dimensional network containing a large amount of water,which has a wide application prospect.However,when hydrogels are placed in a watery environment,they often swell,which not only degrades their mechanical properties,but can also damage surrounding tissue when implanted.The existing methods of preparing swelling controllable hydrogels all require complex multi-step chemical modification,and the operation is complicated.Based on the principle that small molecules can be intersoluble with water before polymerization,and insoluble or hard to dissolve after polymerization,a swelling controllable hydrogel was prepared by adjusting the proportion of materialsBased on the above studies,hydroxypropyl acrylate(HPA)and a large amount of water were introduced.HPA and MTMS were mutually soluble with water at room temperature.After polymerization(PHPA)and polysiloxane were hydrophobic.The swelling performance can be controlled by adjusting the ratio of HEA,HPA and water,and the hydrogel is temperature-sensitive.