Emulsion polymerization of 100% biobased itaconate esters
May 10-15, 2015
Bio-based polymers have been capturing both research and market attention in recent years. The renewable resources of bio-products offer great opportunities to reduce our dependence on petroleum based products. Itaconic acid is a renewable chemical produced at large commercial scale by fermentation of carbohydrates such as corn based dextrose or cane and beat sucrose. The unsaturated vinyl bonds in itaconic acid and its derivatives provide the opportunity for free radical polymerization and to create polymers for various applications. The di-acid functionality of itaconic acid grants good flexibility of its usage during the polymerization. It can be incorporated as-is in a copolymer to increase the polymer surface interaction with substrates. Alternatively, the itaconic acid can react with a desirable alcohol and form a mono-ester and modify its polarity before addition into a copolymer. By reacting itaconic acid with different biobased alcohols, 100% bio-based itaconate esters can be synthesized and then purified for use as reactive monomers. These monomers offer some significant advantages over their acrylic counterparts, such as higher boiling point, low volatility, high hydrophobicity, very low odor and a safer health profile. The polymeric coating typically derived from these monomers exhibit good water resistance and high gloss. Itaconix Corporation has been developing various technologies to utilize itaconic acid and its derivatives as the foundation for different market applications. Of prime interest if the emulsion polymerization process. It allows easy handling of the polymeric materials both during polymerization and during the application of the final product. Easy cleanups and the absence of VOC generating solvents help to create a better health and safety production environment. There are also challenges to this process, particularly when compared to the conventional emulsion polymerization process designed for petroleum based monomers such acrylics and vinyl acetates. Typically polymerization rates are slower, leading to lower instantaneous monomer conversions. In consequence the polymerization conditions require slower monomer feeding profiles and longer reaction times. Also, final polymer chain lengths are shorter due to higher chain transfer reactions during the polymerization. These constraints have to be managed in order to produce market acceptable products. This had been done effectively for pressure sensitive adhesive (PSA) applications. Zero VOC is involved during the synthesis and in the final product. High solids and stable latexes with low glass transition temperatures have been prepared and tested for adhesive applications.
Yvon Durant and Bo Jiang, "Emulsion polymerization of 100% biobased itaconate esters" in "Polymer Reaction Engineering IX", E. Vivaldo-Lima, UNAM; J. Debling, BASF; F. Zaldo-Garcia, CP-COMEX; J. Tsavalas, Univ. of New Hampshire Eds, ECI Symposium Series, (2015). http://dc.engconfintl.org/polymer_rx_eng_IX/15