In the first study PEG, PPG and PTHF polyethers were doubly cationized by Na+, K+ and Cs+. Dissociation of these doubly charged polyethers into singly charged polyethers was studied by means of energy-dependent CID tandem mass spectrometry. A simple collision model for treating multiple collisions taking place in quadrupole-type mass spectrometers has been developed. It was shown that this model can describe the energetics of the fragmentations. The inelasticity ratio for the leucine enkephalin in quadrupole-time-of- flight and quadrupole instruments was determined by applying of the collision model and RRKM algorithm. The collision induced dissociation of the protonated five arm star propoxylated diethylenetriamine polyols was studied under electrospray conditions.