ARS | Publication request: Biobased alternatives to guar gum as tackifiers for hydromulch

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 11, 2012
Publication Date: November 15, 2012
Citation: Vaughn, S.F., Kenar, J.A., Felker, F.C., Berhow, M.A., Cermak, S.C., Evangelista, R.L., Fanta, G.F., Behle, R.W., Lee, E. 2012. Biobased alternatives to guar gum as tackifiers for hydromulch [abstract]. Association for the Advancement of Industrial Crops.

Technical Abstract: Guar gum, obtained from guar [Cyamopsis tetragonoloba (L.) Taub.] seeds, is currently the principal gum used as a tackifier (binder) for hydraulically-applied mulches (hydromulches) used in erosion control. The oil industry’s increased use of guar gum in hydraulic fracturing together with lower global production has driven up the price to levels never previously reached, resulting in the wholesale price of guar gum increasing to as much as $18.00/kg, when historically prices ranged from $1.80 to $2.20/kg. The objective of this research was to determine if other biobased tackifying agents which are research group has been studying are acceptable as alternatives to guar gum. These include defatted camelina and lesquerella seedmeals, corn starch, corn starch-sodium palmitate inclusion complexes prepared from either normal or high amylose starch, pectin, lignin, plantago gum or xanthan gum. Camelina and lesquerella seedmeals were obtained after oil extraction with hexane. Corn starch-sodium palmitate inclusion complexes were produced by jet cooking. Corn starch, pectin, lignin, plantago gum and xanthan gum were used without modification from the suppliers. All of the tackifiers were mixed as dry powders (2.0 g each) with hydromulch (Hydrostraw®, 48.0 g) formulated without a tackifier, to which deionized water (400 ml) was added to form a paste, which was applied evenly to 38.8 cm x 25.9 cm baking pans. The pans were placed in a drying oven at 40 oC for 24 h, and then subjected to simulated rainfall for 1 h at a rate of 6 cm/h in a research track sprayer. The pans were removed from the sprayer and placed in a drying oven for an additional 24 h. Rainfastness index was calculated as: [Weight of hydromulch + tackifier after rainfall (g)/50.0 g] x 100%. Our results indicate that lesquerella and camelina seedmeals, the high amylose corn-starch-sodium palmitate inclusion complex and xanthan gum had higher rainfastness indices than guar. Pectin, plantago gum, methyl cellulose, the normal corn starch-sodium palmitate complex and lignin were equal to guar in rainfastness indices. Only waxy starch had a lower rainfastness index. These results indicate that other tackifiers would be acceptable as replacements for guar gum with cost and availability determining which materials would be used.