Investigation of diene addition on ethylene–propylene (EP) copolymerization with a zirconocene catalyst: Effects of diene types and E/P ratios

Comparative study of copolymerization and terpolymerization of ethylene/propylene/diene monomers using metallocene catalyst

“…It is observed that the diene content of the obtained polymer is dependent on E/P monomer feed ratio, where by increasing the ENB concentration the ethylene content and the productivity of the catalyst system are reduced (Tables II and III). However, diene content may be increased with lower ethylene content of E/P monomer feed ratios, in accordance with other reports 13, 16. Both ethylene and ENB contents of the polymers are increased with [Al] : [Zr] molar ratio up to 500 : 1, however beyond this ratio their contents are decreased in final terpolymer composition (Figs.…”

“…Commercial sample (KEP 270) shows high elastic modulus at low angular frequency close to 22,000 Pa and the terpolymers B0, B1, and B2 show their respective elastic modulus of 5400, 200, 400 Pa. These differences can be due to the high ethylene content of the samples of high crystallinity13 (Fig. 13).…”

“…A calibration curve for samples of known diene was also obtained to determine similar diene content in the obtained polymers. Characterizations of some selected polymers were performed using this technique, assignment of the peaks and the compositional analyses of the samples were being carried out based on published works 13, 18. Determination of the glass transition temperature was performed using DSC PL model STA 780 in temperature range of 25–150°C.…”

“…There is an advantage of metallocene compared to Zigler‐Natta catalyst in EPDM production, both by the desire to avoid the use of toxic vanadium and to exploit the well‐known high activities of the metallocene systems. These catalysts have the ability to allow random distributions of monomers and to provide good control over molecular weight distribution 11–13. The homogeneous metallocene catalysts have been extensively investigated by many researchers 14–16.…”

Terpolymerization of Ethylene/Propylene/Diene Monomers Using (2‐PhInd)2ZrCl2 Metallocene Catalysts

“…In the presence of a diene, it has been reported that the vanadium‐based catalysts exhibit low activities along with toxicity concerns due to the residual vanadium remains in the polymer 13–16. Thus, in order to overcome those problems, an alternative way of using the homogeneous metallocene catalysts has been substantially investigated by many researchers 11, 17–20. The studies show that metallocene catalysts exhibit higher activities and higher incorporation rates of termonomers in the polymer without any noticeable side reactions 21–24.…”