Holography as a tool for mechanistic and kinetic studies of photopolymerization reactions: a theoretical and experimental approach

Effects of absorption and inhibition during grating formation in photopolymer materials

“…where A͓t͔, the time-varying absorbance of the material, 8,9,22 has been included in the expression for the polymerization rate to account for the change in absorbed intensity during exposure. To account for the nonabsorptive losses present, a loss fraction B has been included by defining the polymerization rate parameter as F 0 ͑t͒ = 0 ͑t͒I 0 ␥ ͑1−B͒.…”

“…The expression for the polymerization rate parameter also includes the timevarying function 0 ͑t͒, which we introduce to model the inhibition period present at the start of exposure. [16][17][18]22,23 For the I͑x , t͒ in Eq. (26), the monomer concentration can be written as a cosine series…”

Analysis of the photoabsorptive behavior of two different photosensitizers in a photopolymer material

“…A study of the photochemical kinetics involved during holographic recording in a polyvinylalcohol-acrylamide (PVA-AA) based photopolymer material [1,[3][4][5][6][7] is presented here. Such materials have received much attention in the literature [1][2][3][4][5][6][7][8][9][10][11] and are relatively simple to work with.…”

“…Such materials have received much attention in the literature [1][2][3][4][5][6][7][8][9][10][11] and are relatively simple to work with. In particular, in this paper our aim is to increase our understanding of what takes place inside the material during exposure when using different photosensitizers.…”

Extended model of the photoinitiation mechanisms in photopolymer materials

“…[1][2][3][4] The resulting models attempt to take account of the effects of ͑i͒ the photon absorption, ͑ii͒ the regeneration or recovery of absorptive photosensitizer, and ͑iii͒ photosensitizer bleaching. In this paper, the photoinitiation mechanisms involved during holographic recording in a polyvinyl alcohol/acrylamide ͑PVA/AA͒ based photopolymer [5][6][7][8][9][10][11] is studied. The aim is to precisely predict the number of photons that are absorbed by the photosensitizer, which result in the generation of primary radicals, ED · ͑or R · ͒.…”