Rheology modifiers not only thicken latex paint, but give it the sense of drag found with alkyds, said Rohm and Haas's Walt Gozdan. The drag forces you to put the paint on at a lower spread rate. That contributes to paint film thickness. Rheology modifiers also minimize or eliminate brush marks and roller patterns, reduce spattering, and reduce paint film sagging. Paint formulators also enhance paint flow by adding glycol, or antifreeze, to latexes.
Surfactants give latexes other alkyd-like properties.
That is, they didn't penetrate into all the cracks and grooves of a substrate as quickly as alkyds. Coalescents, or co-solvents, solve a temperature problem associated with latexes. Coalescents counter that tendency, allowing painters to work in less than ideal weather. Defoamers prevent the formation of tiny bubbles that produce craters in the dry paint film, a problem that especially plagues latexes. Both latexes and alkyds rely on mildewcides.