ARS | Publication request: Aqueous carbon black dispersions prepared with steam jet-cooked corn starch

Submitted to: Journal of Applied Polymer Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 9, 2011
Publication Date: April 27, 2012
Citation: Kenar, J.A., Felker, F.C., Fanta, G.F. 2012. Aqueous carbon black dispersions prepared with steam jet-cooked corn starch. Journal of Applied Polymer Science. 126:E418-E429.

Interpretive Summary: Currently used aqueous carbon black dispersions that are prepared using chemical surfactants may be expensive, non-biodegradable, and negatively impact the environment. This research showed that cheap and renewable corn starch can be utilized to effectively disperse hydrophobic carbon black into water by blending and homogenizing the two components into stable aqueous dispersions. This new biobased approach concerning the use of starch to adsorb onto the surfaces of hydrophobic particles like carbon black may have potential in market applications including water-based ink, paint, coating applications, asphalt sealants, decorative concrete colorants, and textiles.

Technical Abstract: The utilization of jet-cooked waxy and normal corn starch to prepare aqueous dispersions of hydrophobic carbon black (Vulcan XC-72R) is reported. Blending carbon black (CB) into aqueous jet-cooked dispersions of starch followed by high pressure homogenization produced stable aqueous carbon black dispersions. The dispersed CB particles were shown to have starch adsorbed onto to the particle surfaces. The adsorbed starch imparts hydrophilic properties to the CB, and after extensive washing to remove dissolved and loosely bound starch the CB particles remained well dispersed in water. Thermal gravimetric analyses (TGA), Fourier transform infrared spectroscopy (FTIR), acid and enzymic starch digestion experiments, and microscopy (light and TEM) were used to characterize the starch coated carbon black particles. The method described herein demonstrates a simple, effective and environmentally friendly method for preparing aqueous CB dispersions.