Factors Influencing Release of Fenac from Polyethylene Matrices

Abstract

Fenac [(2,3,6-trichlorophenyl)acetic acid] and its sodium salt were incorporated in polyethylene matrices under varied conditions to afford a series of herbicide-polyethylene formulations. Diffusion within the matrix determined the rates at which the herbicides were released from the formulations into water. Release rates of the herbicides were altered significantly if (a) the formulation curing conditions were varied, (b) the initial amount of herbicide in the matrix was varied, (c) the solubility of the herbicide was changed, or (d) if an additive was used. The results indicate that herbicide diffuses from the matrix through water-filled cracks and capillary channels.