LAUSR

Abstract The acrylate photocuring system with the high curing rate are widely used in various industries. However, the rapid polymerization kinetics can cause the surge of resin viscosity and the gel point can be reached in advance. This can results in the restriction of molecular chain movement and internal stress release is thus hindered during the photopolymerization. Finally, it usually leads to the poor performance of UV-cured materials with lower double bond conversion and large volume shrinkage and shrinkage stress. In order to understand the relationship between properties and polymerization process, this paper employed the combined technique of the mid-infrared spectrometer and photo-rheometer to monitor the acrylate free radical photopolymerization process. The effects of curing conditions (curing temperature, radiant intensity and sample thickness) and system compositions (diluent functionality, diluent segment length) on the rheological properties and chemical conversion of materials were fully investigated. Finally, a standard protocol is established to evaluate the reactivity, mechanical properties and volume shrinkage of the photocuring system. Simultaneously, the double bond conversion of the reaction system can be achieved through calculation of peak area of IR absorption. A complex nonlinear relationship between the storage modulus, shrinkage stress and double bond conversion is established.