Pore Structure Tuning of Poly( EGDMA ) Biomedical Material by Varying the Temperature of Visible Light Photopolymerization

Porous polymer monoliths were obtained via free radical photopolymerization of ethylene glycol dimethacrylate (EGDMA) in the presence of 70 wt% of the porogen 1‐butanol and an initiating system under visible light irradiation at temperatures ranging from 0°C to 60°C. A rise in temperature from 0°C to 60°C resulted in an increase in the average pore size from 6.0 to 12.6 μm, whereas the porosity of the synthesized polymers remained essentially constant at 76.5 (±1.0)%. Furthermore, the photopolymerization rate of the EGDMA–1‐butanol mixture increased by a factor of 3.3 when the temperature was elevated from 40°C to 60°C. An increase in the pore size in the polymer from 6.0 to 12.6 μm, resulting from the polymerization temperature increase, leads to a twofold decrease in the material's strength from 1.09 to 0.55 MPa and a decrease in Young's modulus from 4.38 to 3.37 MPa. Thus, we propose a simple and effective method to control the pore size while maintaining constant porosity by varying the temperature during visible‐light photopolymerization of a fixed‐composition formulation. This approach is promising for the fabrication of porous biomedical materials based on biocompatible polymers, such as poly(EGDMA).