Six new fluorescent derivatives of 1,8-naphthalimide were synthesized. Three were dyes, and three were fluorescent whitening agents (FWAs) containing a tetramethylpiperidine (TMP) stabilizer fragment. The FWAs were obtained under phase-transfer catalysis, conditions. Five of the compounds were copolymerized with methyl methacrylate, so copolymers with all intense color and/or fluorescence stable against solvents were obtained. The chemical bonding of the synthesized monomers ill the polymers was confirmed spectrophotometrically. The participation of the monomer compounds did riot significantly affect the process of copolymerization Or the molecular masses of the obtained copolymers. The quantity of chemically bonded naphthalimide monomer ill the copolymers was determined to be over 60%. The spectral properties Of the compounds, and their photostability ill solution and ill the copolymers were studied. The influence of the compounds Oil the photostability of the copolymers was determined. The compounds, especially those containing a stabilizer (TMP) fragment ill their molecules,, showed positive stabilizing effect oil the photodegradation of poly(methylmethacrylate). Polyamide fabrics with 2-allyl-6-hydrazino-benzo[de]isoquinoline-1,3-dione, 2-allyl-6-(2-amino-ethylamino)-benzo[de]isoquinoline-1,3-dione, and 2-chloro-N'-(2-methyl)-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinoline-6-yl) acetohydrazide were dyed, and materials with all intense yellow color and fluorescence were obtained. Cotton fabrics were whitened with 2-(2,2,6,6-tetramethyl-piperidin-4-yl)-6-methoxy-benzo[de]isoquinoline-1 ,3-dione, 2-(2,2,6,6-tetramethyl-piperidin-4-yl)-1,3-dioxo-2,3-dihidor-1H benzo[de]isoquinoline-6-oxy]ethyl-2-methacrylate, and materials with bright whiteness and intense bluish fluorescence were obtained. (c) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 111:1991-1998, 2009