Attempts to introduce the azo chromophore into poly(methyl methacrylate) (PMMA) molecular chains were made in search for a new approach to obtain functionalized-PMMA (f-PMMA) with high glass transition temperature and an adequate azo content. A novel functionalized monomer, 4,4'-diacryloyloxyazobenzene (DAOAB), was synthesized and used as grafting agent in the polymerization of methyl methacrylate. H-1-NMR spectrum, FTIR spectrum, elemental analysis, and MDSC measurement confirmed that the proposed structure of DAOAB was synthesized successfully. Furthermore, the thermal properties and photochromic behavior of f-PMMA samples were also analyzed by DSC, TGA, and UV-visible spectroscopy. The results have shown that f-PMMA exhibited a better photochromic behavior and considerably improved thermal properties than pure PMMA.