the effect of polycarboxylate superplasticizer on thermal stability and the kinetic thermal
decomposition of oPc without and with 1.0 and 1.5% wt% plasticizer has been studied at
temperature range of 30-1000 oc. the study was done by means of thermogravimetry (tG)
technique under non-isothermal condition at a heating rate of 10 k/min. the results showed
that the decomposition occurs for the superplasticized and neat oPc paste in three steps. the
neat oPc was found to decompose at higher temperatures than those for the superplasticized
paste. the kinetic parameters for each one of the decomposition steps were calculated through
four calculation methods and the kinetic mechanisms were determined from the thermal data
analysis using 35 solid state reaction models. the results showed that the mechanisms of
decomposition steps depend on the percentage of the superplasticizer added to the paste. the
thermodynamic parameters ΔS#, Δh# and ΔG# were also computed and discussed. |
