[en] A Pomeranchuk cell is a refrigerator which can absorb heat at temperature lower than 0.3 K by converting low entropy liquid ³He into high entropy solid. Liquid is converted into solid by increasing its pressure. ⁴He is then used to compress some deformable wall to provide the necessary increase of pressure. The authors have built a Pomeranchuk cell entirely made of plastic, the envelope being made of epoxy and the flexible wall made of polyimide ''Kapton''. ''Kapton'' has low elastic modulus of E = 6 x 10⁹ N/m² and relatively high ultimate tensile strength of σ = 3.4 x 10⁸ N/m², as compared to treated beryllium copper with E asymptoticaly equals 2.7 x 10¹¹ N/m² and σ = 1.3 x 10⁹ N/m². The same stress produces 10 times more deformation in ''Kapton'' than in BeCu, in a reversible region. If a thin walled cylinder constrained on both extremities has a radius R, the increase in radius, ΔR, when pressure P is applied, is given by Δ R = (PR²/Eh) [1 - exp(-kx) (sin kx + cos kx)]. Where E is elastic modulus, h is wall thickness, x is axial distance from the origin, and k = 4√3(1- μ)/√hR asymptoticaly equals 1/√hR. The smallest cell having been built has the internal radius of 0.4 cm, length of 1.5 cm and wall thickness of 6 x 10^-3 cm. For these dimensions, ΔR is nearly maximum at x = 0.1 cm, as seen by solving the equation. (Kobatake, H