Self-reinforcement of three dimensionally printed polymethyl methacrylate

This study shows the use of heat-cured MMA/PMMA liquid mixture, varying from 0% to 12% PMMA, as reinforcing phases to enhance the mechanical properties of three dimensionally printed polymethyl methacrylate based specimens by means of infiltration. It was observed that this self-reinforcement could increase flexural properties of the samples significantly, up to a factor of 5 for flexural modulus and a factor of 27 for flexural strength. Degree of reinforcement depended on the amount of initial binder content in the as-fabricated green 3DP specimens and the ratio of MMA:PMMA in the reinforcing mixture. Decreasing initial binder content in the green specimens increased the efficiency of reinforcement. This is related to the increased amount of initial porosity in the green 3DP specimens with decreased binder content which the reinforcing infiltrant can diffuse into. The MMA/PMMA infiltrant liquid containing less than 10% of PMMA was able to diffuse and reinforce the structure. Greater amounts of PMMA than this level yielded high viscosity fluid which hardly flowed through the specimens.