The polyurethane (PU) latex interpenetrating polymer networks (LIPN) with high contents of the epoxy resin (EP) were prepared

using polytetrahydrofuran glycol (PTMG) and polybutylene adipate (PBA) as soft segments respectively.The structure and properties of the samples with different soft segments were investigated by FTIR

DMA and AFM.The results revealed that the LIPN had formed and with no chemical bond between PU and EP.PU and EP had higher interpenetrating properties in LIPN and lower degree of phase separation with the increase in the content of EP when using PBA as the soft segments because the better compatibility between EP and PBA.The PU samples generally had a higher tensile strength when using PBA as soft segments compared to the samples using PTMG as soft segments

but because PBA and EP had higher interpenetrating properties

the samples showed obviously synergistic effect of IPN

the moving of PBA soft segments were limited more by epoxy resin compared with that of PMTG soft segments

resulting in the tensile strength of LIPN samples with high contents of the epoxy resin decline faster

in the same time the glass transition temperature of the LIPN samples has also rising faster.The solvent resistance of the LIPN using PBA as soft segments is vastly superior to that of the samples using PTMG as soft segments.