Thermal decomposition of poly(1,4-dioxan-2-one)

To evaluate the feasibility of poly(1,4-dioxan-2-one) (PPDO) as a feed stock recycling material, the pyrolysis kinetics of PPDO were investigated. The pyrolysis of PPDO exclusively resulted in the distillation of 1,4-dioxan-2-one (PDO). From thermogravimetric measurements conducted at different heating rates, the kinetic parameters of the pyrolysis: activation energy, E-a = 127 kJ mol(-1); order of reaction, n = 0; and pre-exponential factor, A = 2.3 x 10(9) s(-1), were estimated by plural analytical methods. The estimates show that the decomposition of PPDO proceeds by unzipping depolymerization as main reaction and random degradation process with lower E-a and A values. Equivalent isothermal degradation curves calculated from the thermogravimetric curves were supported by experimental isothermal degradation data. The calculation that PPDO is converted smoothly into PDO at 270 degreesC agrees with the reported ceiling temperature of PPDO. (C) 2000 Elsevier Science Ltd. All rights reserved.