hexahydropyrimidine and mixtures thereof in combination with the alcohols methanol ethanol propanol isopropanol butanol isobutanol c 10 c 20 alcohol blends c 12 c 36 guerbet alcohols behenyl alcohols and mixtures thereof as indicated above the polymeric imides of the invention may contain a mixture of different species it is also within the scope of the invention to provide a composition comprising a mixture of two or more of said polymers the pour point depressant additive of the present invention is especially useful in crude and or fuel oils having a relatively high wax content e g a wax content of 0 1 to 20 by weight per weight of fuel preferably 3 0 to 4 5 such as 3 5 to 4 5 wt measured at 10 u00b0 c below wax appearance temperature wat the polymer is preferably soluble in the oil to the extent of at least 10 000 ppm by weight per weight of oil at ambient temperature however at least some of the additive may come out of solution near the cloud point of the oil and function to modify the wax crystals that form the pour point depressant additive of the present invention can be employed alone or it may be combined with other additives for improving low temperature flowability and or.