POLYURETHANE POLYETHYL ACRYLATE INTERPENETRATING POLYMER NETWORKS - THERMAL-DECOMPOSITION KINETICS/

The thermal decomposition kinetics of polyurethane/polyethyl acrylate interpenetrating polymer networks (PU/PEA IPN) were studied by means o f thermogravimetry and derivative thermogravimetry (TG-DTG), and compa red with those of polyurethane (PU) and polyethyl acrylate (PEA). The decomposition temperature (T-i) of PU/PEA IPN was found to be higher t han T-i of PEA, but lower than Ti of PU. Thermal decomposition kinetic parameters, n and E, estimated using Coats-Redfern method, are found for PU/PEA IPN, PU and PEA to be 1.6, 1.9 and 1.1, and 196.6, 258.6 an d 139.2 kJ mol(-1), respectively. The results show that PU/PEA IPN is neither a simple mixture of PU and PEA nor a copolymer of them. The me chanism of thermal decomposition of PU/PEA IPN is different from those of PU and PEA. The special network in PU/PEA IPN effectually protects weak bonds in the molecular chain of PU and PEA.