ABSTRACT
76A study was conducted to investigate the influence of three adjuvants, viz., two surfactants (Atlox 3409F and Triton X-114) and a cosolvent (Dowanol TPM), abbreviated as Atlo-3409, Trit-1 14, and Dow-TPM, respectively, on spray atomization, droplet spectra, and deposit patterns of four fenitrothion formulations. Spray atomization was carried out a laboratory chamber using a spinning disc atomizer, and droplets were sampled with Kromekote cards and deposits were collected on glass plates. Physical properties measured were relative viscosity, surface tension, volatility, and apparent viscosity-shear rate relationship. Between the two formulations containing Atlo-3409 and Dow-TPM, the one containing 1.5% (v/v) of each adjuvant provided a higher proportion of small droplets and lower deposits than the formulation containing 1.5% of Atlo-3409 and 4% of Dow-TPM. Between the other two formulations containing Trit-114 surfactant, the one containing 7% adjuvant was more pseudoplastic than the one containing 5% adjuvant. However, both formulations provided similar DN.5 and Dv 5, although the formulation with greater pseudoplasticity provided more droplets per square centimeter on the sample cards and greater deposits on glass plates. Thus, the droplet spectra, droplets per square centimeter, and deposits on glass plates were all relatable to the physical properties of the formulations studied.
