Highly holographic diffraction efficiency and recording stable macromolecule photopolymer by introducing cross-linker vinyl-POSS

Abstract

The cross-linked photopolymer vinyl-POSS (Vi-POSS)-phenanthraquinone doped poly methyl methacrylate (PQ/PMMA) was successfully fabricated via a one-pot free radical thermal polymerization technique by incorporating a Vi-POSS cross-linker into PQ/PMMA. The residual C=C bonds on the Vi-POSS branches after cross-linking significantly enhanced the holographic performance, achieving a high diffraction efficiency of 83% and a sensitivity of 0.49 cm J−1, while the cross-linked polymer matrix reduced volume shrinkage to 0.28% (compared to 64%, 0.33 cm J−1, and 0.39% for PQ/PMMA). Moreover, the Vi-POSS-PQ/PMMA sample exhibited excellent stability, with a bit error rate maintained at ∼0.5% over a broad holographic recording time range (3–13 s), demonstrating its suitability for data storage applications by mitigating the effects of laser power fluctuations or system instability. Further experimental analysis confirmed the synthesis of a 3D cross-linked macromolecular network with Vi-POSS as the core. The residual C=C bonds in the Vi-POSS-PQ/PMMA matrix originated primarily from Vi-POSS, and a hexatomic cyclic –C–O–C– structure formed between Vi-POSS and PQ upon beam exposure. In conclusion, this study not only elucidates the microphysical and chemical mechanisms underlying the enhanced holographic performance of Vi-POSS-PQ/PMMA but also proposes a novel strategy to optimize storage stability for holographic data storage applications.