Investigation of polymerization rate in an acrylamide-based photopolymer using Raman spectroscopy

Raghavendra Jallapuram, Dublin Institute of Technology
Izabela Naydenova, Dublin Institute of Technology
Hugh Byrne, Dublin Institute of Technology
Suzanne Martin, Dublin Institute of Technology
Robert Howard, Dublin Institute of Technology
Vincent Toal, Dublin Institute of Technology

Document Type Conference Paper

R. Jallapuram, I. Naydenova, H. J. Byrne, S. Martin, R. G. Howard, V. Toal, “Investigation of polymerization rate in acrylamide-based photopolymer for holographic recording”, SPIE proceedings of Opto-Ireland conference, V.5826, 75-82, 2005.doi:10.1117/12.605416


Diffusion models predict that polymerization and diffusion rates are the key factors that control the dynamics and the final properties of a holographic grating recorded in a photopolymerizable material. Diffusion rates during the initial phase of holographic recording have already been studied and reported. We now report the investigation of the polymerization rate in an acrylamide-based photopolymer using Raman spectroscopy. The polymerization rate constant was estimated by monitoring the intensity of the characteristic Raman peaks at 1284 cm-1 corresponding to the bending mode of CH vinyl bond in acrylamide and 1609 cm-1 corresponding to the carbon-carbon double bond (C=C) in acrylamide as a function of illumination time. The dependence of the residual monomer concentration on the exposure time was fitted using a mono exponential fitting function. The value of the polymerization constant was estimated to be 0.043 s-1mW-0.5. A comparison with some other photopolymer systems reported in the literature reveals that the acrylamide-based photopolymer system is characterized by a faster polymerization rate constant. The results from the present study give significant information for better understanding of the process of holographic recording in acrylamide-based photopolymer system.