Synthesis and characterization of monoalkyl maleates and their use in emulsion polymerization of vinyl acetate

Different monoalkyl maleates (MAM) have been synthesized and used as functi onal (co)monomers in the emulsion polymerization of vinyl acetate (VAM). Vi nyl acetate was added either in batch or semicontinuously in order to impro ve the incorporation yield of the comonomers. The monoalkyl maleates and th e different latexes obtained were fully characterized using nuclear magneti c resonance spectroscopy (H-1 NMR and C-13 NMR), differential scanning calo rimetry (DSC) and gel permeation chromatography (GPC). We demonstrated that the monoalkyl maleates were entirely reacted and incorporated in the copol ymers. When using a semicontinuous addition process for vinyl acetate, it w as found that the monoalkylmaleates were mostly contained into copolymers w hich are extractable from the latex particles by centrifugation. We showed that these extractable copolymers contain around 28 weight percent of monoa lkyl maleate which concentration is larger than the concentration of monoal kyl maleate in the feed. The incorporated monoalkyl maleates contribute to a decrease of the glass transition temperature of the copolymers.