The effect of some straight-chain semifluorinated n-alkanes F(CF2)n(CH2)mH on the cloud point and pour point of a vaseline oil was investigated using the apparatus and procedure reported in the ASTM D2500-81 and D97-66 Standard Methods respectively. The obtained values were plotted against concentration in such a way as to stress the influence of the relative chain lenghts of the fluorocarbon and hydrocarbon segments in the additive molecule. Increased values of the cloud and pour points of the used vaseline oil were generally determined; compounds having the shortest fluorocarbon fragment led to the smallest changes.
