Statistical Copolymers of Norbornene and 5-Vinyl-2-norbornene by a Ditungsten Complex Mediated Ring-Opening Metathesis Polymerization: Synthesis, Thermal Properties, and Kinetics of Thermal Decomposition
Statistical Copolymers of Norbornene and 5-Vinyl-2-norbornene by a Ditungsten Complex Mediated Ring-Opening Metathesis Polymerization: Synthesis, Thermal Properties, and Kinetics of Thermal Decomposition
Georgios Floros
Fotini Agrafioti
Alexios Grigoropoulos
Patrina Paraskevopoulou
Konstantinos Mertis
Maria Tseklima
Maria Veli
Marinos Pitsikalis
Statistical copolymers of norbornene (NBE) with 5-vinyl-2-norbornene (VNBE) were prepared by ring-opening
metathesis polymerization, employing the triply bonded ditungsten complex Na[W2(μ-Cl)3Cl4(THF)2].(THF)3. NMR measurements revealed that the side vinyl groups of the VNBE monomer remain intact during the copolymerization reaction. The reactivity ratios were estimated using the Finemann–Ross (FR), the inverted FR, and the Kelen–Tudos graphical methods. Structural parameters of the copolymers were obtained by calculating
the dyad sequence fractions, which were derived using the monomer reactivity ratios. The glass transition temperatures, Tg, of the copolymers were measured by differential scanning calorimetry measurements and were examined in the frame of several theoretical equations allowing the prediction of these Tg values. The best fit was obtained using methods that take into account the monomer sequence distribution of the copolymers. Finally, the kinetics of the thermal decomposition of the copolymers was studied by thermogravimetric analysis
in the frame of the Ozawa–Flynn–Wall and Kissinger methods.
(EN)
