Photopolymerization 3D Printing Low-swelling Degradable Materials

Photopolymer 3D printing is a high-precision,customizable,and fast additive manufacturing method.These features give good prospects for photopolymerization 3D printing technology,especially in tissue engineering.However,photopolymerized 3D printing is formed by liquid photo-sensitive resin(usually small molecules or oligomers)cross-linked by light and stacked layer by layer.The printed model cannot be degraded.For some applications,such as tissue engineering,biology The field of materials is very unfavorable;for many of the materials currently printed by photopolymerization,they are often used in intermediate models,such as models for dental(replacement of the original plaster model),which are only applied briefly and become waste.The post-processing of these models is also bound to become an important issue.Therefore,the development of a degradable and photopolymerizable 3D printing resin is of great significance for the development and application of 3D printing technology.This subject synthesizes a D-glucose dilactone dimethacrylate carbamate(GDMA)composed of a urethane bond,an acrylate double bond,and a saccharide derivative.The urethane bond in the GDMA structure can be degraded under alkaline conditions,and the degradation rate is different depending on the strength of the basicity;the acrylate bond in the structure provides a photopolymerizable functional group;the lactone of the saccharide derivative The skeleton not only provides better biocompatibility,but also the lactone ring compound provides good mechanical strength to the final material,and the lactone ring itself can be hydrolyzed and opened in water to form a carboxylic acid,which is a subsequent mineral in the organism.Provides a good binding site.GDMA was copolymerized with HEMA to produce a biodegradable and photopolymerizable 3D printed material.(1)Through the design of the formulation and the swelling degree,volume shrinkage,mechanical properties,thermomechanical analysis,etc.of the material,the test results show that with the increase of the cross-linking agent of the sugar derivative,the properties of the material are significantly improved.The degree of swelling is at least 10%,the volume shrinkage is less than 12%,and the tensile strength can be as high as 70 MPa.(2)The degradation performance of the material shows that the material is very stable in the acidic environment.When the pH value is greater than 7,the material exhibits degradability,and the degradation rate increases with the increase of pH value.At a pH of 7.5,the polymer degraded by 40%at 10 weeks.(3)By chelation of calcium ions with carboxyl groups,neutralizing the carboxyl functional groups generated by the hydrolysis process,the toxicity test of the sample leachate showed that the growth state of the positive group cells after chelation by calcium ions was much better than that of the negative group,indicating the preparation of Degradable materials are ideal for cell growth.(4)The 3D printing results show that through the 3D printing model design and formula design,the designed material can print a fine structure with a pore size of 200 microns.