Theoretical and experimental analysis of chain transfer agents behaviors in photopolymer material
The Non-local Photo-Polymerization Driven Diffusion (NPDD) model indicates how a material's performance might be
improved, and provides a tool for quantitive comparison of different material compositions and to predict their
fundamental limits. In order to reduce the non-locality of polymer chain growth (i.e the non-local response parameter, σ)
and to improve the spatial frequency response of a photopolymer material, we introduce the chain transfer agent (CTA).
In the literature, extensive studies have been carried out on the improvements of the non-local response modifying by the
CTA, sodium formate, in the polyvinyl alcohol-acrylamide (PVA/AA) material. In this article, i) based on the chemical
reactions of CTA, we extended the CTA model in the literature; ii) we compare two different CTA materials, sodium
formate and 1-mercapto-2-propanol without cross-linker in order to obtain the experimental confirmation of the
reduction in the average polymer molecular weight is provided using a diffusion-based holographic technique; iii) we
examine the non-local responses of several spatial frequencies with the two CTAs. Using the extended CTA model it is
demonstrated that the CTA has the effect of decreasing the average length of the polyacrylamide (PA) chains formed,
thus reducing the non-local response parameter, especially, in the high spatial frequency case.
This paper was published in SPIE Proceedings Vol. 8074