Volume 2, Issue 7 (July 2005)
New Value-Added Polymeric Dispersants and Uses Thereof in Agricultural Formulations
Polymeric dispersants are dispersants of choice for formulating suspension concentrates, suspoemulsions, and solid delivery systems (WP, WDG, and Tablets). We have developed a new line of polymeric dispersants, as 25 % aqueous solution, based on partially neutralized methyl vinyl ether maleic acid half esters (ethyl/butyl) copolymers (MVE-MAHE), (with trade name EASY-SPERSE®). They were used in formulating suspension concentrates and aqueous dispersions for a host of active ingredients like herbicides, insecticides, fungicides, and other growth regulators, organic dyes, inorganic pigments, including certain water-insoluble polymers. Some of these dispersions also showed suspensibility above 80 % and rainfastness at use level concentrations.
Other commonly used polymeric dispersants are: Lignosulfonates, Naphthalene sulfonate formaldehyde condensate (NSFC), Poly acrylates, and olefin maleic acid co-polymers. Their film forming properties and binding efficacy can be improved when used with pyrrolidone co-polymers.
Our recent findings show synergy between vinylpyrrolidone homo/co-polymers and commonly used polymeric dispersants as above. Further, a combination of Polyvinylpyrrolidone and polymeric dispersants showed built-in rainfastness in suspension concentrates. Examples of prototype formulations and a working model explaining the synergistic role of polyvinylpyrrolidone are provided. Solid composites from Polyvinylpyrrolidone and MVE-MAHE were prepared via spray drying the liquid slurries. The solid dispersants with Polyvinylpyrrolidone incorporated will be useful in formulating solid delivery systems.