Etude des morphismes pr{\'e}servant les mots primitifs

This article provides a reminder of some properties of primitive words and the morphisms that preserve them. Their proofs, which I have more or less revised, are included. This makes the article almost self-contained. I also contribute by giving some properties of primitive words, but especially by showing that a morphism without powers k($\ge$ 5) is primitive and that a uniform morphism without powers k($\ge$ 2) is primitive.