Three Merrifield-type diaminated polystyrene-Cu(II) resins were synthesized, and the hydrolytic P-F bond cleavage reaction rates of the catalyzed O-isopropyl methylphosphonofluoridate (GB) and O-pinacolyl methylphosphonofluoridate (GD) were surveyed. The hydrolysis of GB and GD using Cu(II)-loaded polymers occurred via an intermediate complex mechanism where a rapid equilibrium (K_f) that formed an intermediate complex between the substrate and the Cu(II)-loaded polymers was followed by a rate determining hydrolysis step (k₁). The measured activation parameters for k₁ were ΔH^‡ : 17.75±0 .98 kJ/㏖, ΔS^‡ : -218.42±35 J/㏖ K, E^o_a: 20.22±0.98 kJ/㏖ for GB and ΔH^‡ : 11.16±1.15kJ/㏖, ΔS^‡: -258.57±3.93J/㏖ K, E^o_a: 13.64±1.15kJ/㏖ for GD. The standard enthalpy/entropy changes corresponding to the intermediate complex formation constant (K_f) were H^0: 37.05±2.19 kJ/㏖, S^0: 163.12±7.49 J/㏖ K and H^0: 18.59±2.04 kJ/㏖, S^0: 111.92±6.98 J/㏖ K for GB and GD, respectively. An analysis of k₁, within a pH = 6.5∼8.0 range suggested that the hydrolysis (k₁) of GB and GD consisted of consecutive reaction mechanisms where the deprotonation equilibrium of the ligated H₂O (K_a,: pK_a=7.29 (GB) and 7.06 (GD)) was followed by an intramolecular attack by the resulting OH^- ligands (k: 0.0188 sec^(-1) (GB) and 0.00390 sec^(-1) (GD))