These fluids defined the influence of DUEVs on the number of ribs formed as a function of roll velocities and the gap setting between rolls, and they are used here to differentiate the relative role of HSVs and DUEVs in spray applications.
The blends used in this study consist of variable component ratios among individual sets (Table 1), and each set is formulated to produce the same viscosity/shear rate profile, storage modulus (G'), and surface tension, but with different DUEVs, allowing for separate control of the shear and extensional responses.
DUEVs were measured via a fiber extension method that has been described previously.
An alternate explanation for the spray discrepancies: the DUEVs of the high [M.
v] HEC blends produced higher DUEVs was the most interesting observation.
The comb has a significantly higher molecular weight than the telechelic HEURs and it has a determinable (37) DUEV at a 1.
25 wt% HEC, below that used in this coatings study, the DUEV was between 1 and 2.
29]-comb-HEUR coating would have the highest projected coating DUEV of the associative thickener coatings studied.
v] HEC thickened large particle (477 nm) size latex coating is shear-thinning, like the large hydrophobe telechelic HEUR formulation; however, the HEC formulation has a significant DUEV, which alone can account for the spray profile.
This could be related to the DUEV of these systems, but in the sharkskin type of pattern that is sometimes developed, it is thought that other modes of extensional viscosity are present (i.
The particle velocity patterns of the four formulations that provided spray patterns also follow the velocities profiles noted in latex paints with increasing DUEVs