Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/21/2004
Publication Date: 3/28/2004
Citation: Selling, G.W., Sessa, D.J. 2004. Effect of water and tri(ethylene) glycol on rheological properties of zein. American Chemical Society. p. 75.
Technical Abstract: Before conducting larger scale studies utilizing zein on an extruder, it is necessary to carry out experiments on a torque rheometer. Water and tri(ethylene glycol)(TEG) are known plasticizers for zein, however, the effects these materials have on zein has not been studied using a torque rheometer. The amount of each plasticizer in zein was varied between 5 and 30%. The plasticizers were tested separately and in combination. It was demonstrated that water and TEG interact differently with zein. TEG was more effetive on a molar basis. When the amount of water was above 10%, network formation occurred and the resulting torque increased exponentially with time. TEG will allow network formation at elevated temperatures. When TEG was used at lower temperatures, torque increased linearly with time. When TEG and water combination were used to plasticize zein, the resulting rate of torque increase was dissimilar to that obtained when either plasticizer was used alone. Previously unobserved multiple state changes for zein mixtures were observed suggesting that under suitable conditions the formation of networks is an ongoing process. The energy of activation of flow was determined when using 20% TEG.