2.1. SMX static mixers
The foams are elaborated by gas injection in a continuous flow
of liquid using the static mixers SMX™ or SMX+™ (Sulzer, Winterthur,
Switzerland). They have a respective inside diameter of 10
and 6 mm in diameter. One element of SMX consists of stainless
steel crossed bars at angles of 45 over flow direction with ratios
of length to diameter equal to one. Each element is rotated 90
prior to the previous element. Characteristics of the static mixers
geometry are given in Table 1.