Shrinkage during film formation

Film Formation and Propoties.— Work on film preparation and subsequent processing of 2GT has been limited to studies on the transverse constriction and stresses observed during uniaxial orientation and the problems associated with the maintenance of planarity during heat relaxation. Orientation and shrinkage have been discussed in a number of papers with studies on orientational setf-ieinforcement and relaxation and its effects on orientation. The effect of the interaction of films with organic liquids has promoted studies on the structural arrangements in liquid-induced crystallization of cold-drawn 2GT films, and the effect of crystallization on adhesion and cohesion. ... 

FIGURE 2.16 The effect of minimum film-formation temperature (MFFT) of a dispersion on its drying behaviour. Primal (Rohm Haas) dispersions were allowed to dry at room temperature, =21 °C, in a silicone rubber mould. An MFFT above room temperature results in incomplete coalescence of particles and poor film formation. The cracks and distortion that occur in the films result from the movement of water and shrinkage during drying, (a) AC-34 MFFT, 12 °C. (b) AC-73 MFFT, 37 °C. (c) B-85 MFFT, 90 °C. 

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