Thermodynamic modeling of density, viscosity and critical micelle concentration of aqueous Tween and Span solutions via Cubic plus association equation of state

•The CMCs of Span 60, Span 80, Tween 60, and Tween 80 were modeled via CPA EoS.•Tweens and Spans were modeled for the first time considering 3 × 2B association scheme.•Liquid mixture viscosity and density were predicted marvelously at different temperatures.•Liquid mixture viscosity was compared using FT, FVT, LBC, and Assael models via the CPA predicted density.