Revista Brasileira De Herbicidas 2005; 4(2)
Study of the surface tension in drops of solutions with surfactants of agricultural use
DOI: 10.7824/rbh.v4i2.21
The present work had the objective to study the behavior of the superficial tension in solution drops elaborated with different surfactants concentrations. To analyze the tension he/she made himself weight of the drops formed in the extremity of the burette, with the following combined treatments of form factorial (15×12) 15 surfactants (Ag-Bem, Agral, Aterbane BR, Agrex, Break Thru, Extravon, Energic, Fixade, Gotafix, Haiten, Herbitensil, Iharaguem, Lanzar, Silwet L-77 and Will Fix) and 12 concentrations (0; 0,001; 0,0025; 0,005; 0,01; 0,025; 0,05; 0,1; 0,25; 0,5%; 1 and 2%) in to total of 180 treatments. Analyze it statistics of the dates it was accomplished with I aid of the SAS program and it goes it analyzes of regression, the model of adjusted Mitscherlich was adopted and modified it goes the obtained it dates. It was observed that the surfactants organosilicons Break Thru and Silwet reduced the surface tension significantly (19,87 and 19,08 mN/m; respectively) and they presented the highest coefficients of effectiveness (169,81 and 143,43). Will Fix and Agrex in spite of they have presented low coefficients of effectiveness (1,52 and 4,01; respectively), they reduced the superficial tension significantly (24,71 and 29,29 mN/m) they put in the close high concentration attn 2% v/ v. The other surfactants presented quit close minimum tensions; the comparison among them can be made exclusively by the coefficient of effectiveness.
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