Calorimetric study of 5‐trimethylsilyl‐2‐norbornene, of its polymerization process and of poly(5‐trimethylsilyl‐2‐norbornene) from 5 to 600 K at standard pressure

Abstract

AbstractThermodynamic properties of 5‐trimethylsilyl‐2‐norbornene (TMSNB) and poly(5‐trimethyl‐silyl‐2‐norbornene) (PTMSNB), viz. the temperature dependence of the isobaric heat capacity Cop of the monomer between 10 and 330 K and of the polymer from 7 to 600 K, were studied by adiabatic vacuum and differential dynamic calorimetry. Temperature and enthalpy of monomer melting as well as parameters of glass transition and glassy state of the monomer and the polymer were determined. From the experimental data, the thermodynamic functions H°(T)‐H°(0), S°(T) and G°(T)‐H°(0) were calculated for TMSNB in the range of 0 to 330 K and for PTMSNB from 0 to 380 K. In a differential automatic calorimeter, the enthalpy of polymerization of TMSNB to PTMSNB in toluene solution was measured at T = 301 K and p = 101,325 kPa. Under similar physical conditions and in the same calorimeter, enthalpies of dissolution for the monomer and the polymer were estimated. The results were used to calculate the enthalpy, entropy and Gibbs function of bulk polymerization of TMSNB in the range of 0 to 380 K at standard pressure. The ceiling temperature of the polymerization process was also evaluated.