A method of manufacturing cyclophosphazenes PFPE derivatives to be used in the lubrication of magnetic recording media is herein provided. The method comprises: a) a (per)fluoropolyether (PFPE) polyol [PFPE (Ppol)] comprising a fluoropolyoxyalkylene chain (Rf) having two chain ends, each chain end comprising at least one hydroxy group, and b) the corresponding alkoxide of perfluoropolyether (Ppol) [PFPE (Palk)] wherein the equivalent concentration of PFPE (Palk) in PFPE (Ppol) is lower than 30%, preferably ranging from 5% to 15%; 2) contacting mixture (M) with a perhalocyclophosphazene (CPhalo) to provide a mixture (M1) containing an equivalent ratio of PFPE (Palk)/(CPhalo) of at least 1; 3) allowing mixture (M1) to react until complete disappearance of P—Cl groups to provide a mixture (M2); 4) submitting mixture (M2) to hydrolysis to provide a mixture (M3); 5) optionally removing (Ppol) from mixture (M3) to provide a mixture (M4). A method of purifying mixture (M4) is also herein provided.