¹³Carbon nuclear magnetic resonance of ethylene–propylene–1‐decene terpolymers

Abstract

Many studies have been reported on the 13C NMR characterization of ethylene–α‐olefin copolymers, but only a few have been reported on terpolymers. The incorporation of an α‐olefin into the polyethylene chain changes the structure and, consequently, the properties of the polymer obtained. Looking for new products, we obtained a series of ethylene–propylene–1‐decene terpolymers with the metallocenic system rac‐ethylene bisindenyl zirconium dichloride/methylaluminoxane. We performed a complete 13C NMR characterization of these terpolymers qualitatively and quantitatively. Here we present a detailed study of the 13C NMR chemical shifts, triad sequence distributions, monomer average sequence lengths, and reactivity ratios for these terpolymers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2531–2541, 2003

13Carbon nuclear magnetic resonance characterization of ethylene–propylene–1-octadecene terpolymers and comparison with ethylene–propylene–1-hexene and 1-decene terpolymers

“…As the catalyst used gives mainly isotactic sequences (see the propene region 19.4-21.7 ppm) the major peak at 30.00 ppm (peak 17) can be attributed to the isotactic sequences (mm) and the minor peak at 29.91 ppm (peak 16) to the heterotactic (mr) ones. Others attributions such as those of resonances 9,10, 12 and 13 where already discussed in a previous paper [10].…”

“…The difference in the assignments for the terpolymers with the 1-octadecene in relation to the terpolymers with 1-decene [10] is in the contribution of the carbons of the branch in the region of 29.91-30.00 ppm, that for 1-decene corresponds to one carbon and for 1-octadecene to nine carbons (5-13B 16 ). Propylene-1-octadecene copolymers and ethylene-propylene-1-octadecene terpolymers with high amount of propylene present two resonances for carbons 5-13B 16 in OOO, POP and POOCOOP triads, for terpolymers with low amount of propylene peak 16 is not present, as it can be seen in Fig.…”

“…1 shows the 13 C NMR spectra of ethylene-1-octadecene, propylene-1-octadecene copolymers and three spectra of ethylene-propene-1-octadecene terpolymers with different amount of comonomers. The assignments were done using Lindeman and Adams [17], literature data [10,18,19] and 13 C NMR spectra of 1-octadecene and propylene homopolymers, ethylene-propylene, ethylene-1-octadecene and propylene-1-octadecene copolymers and ethylene-propylene-1-octadecene terpolymers with different amounts of comonomers, obtained in this work. Chemical shift assignments are shown in Table 1.…”

“…The concentration of ethylene in the solution was estimated by using the equation quoted by Kissin [13] and the concentration of propylene in toluene during the polymerization reaction was calculated using the correlation obtained by Villar and Ferreira [14] and described in detail in a previous work [10]. Under these conditions the monomer concentration in the liquid phase were C E (mol/L)/C P (mol/L)Z0.103/0.000; 0.098/0.016; 0.093/ 0.032; 0.078/0.079; 0.052/0.158; 0.026/0.237; 0.010/0.285; 0.005/0.301; 0.000/0.471.…”

“…Following a series of works on terpolymers [10][11][12] here we report a detailed 13 C NMR study of ethylene-propylene-1-octadecene terpolymers, synthesized with the metallocene catalyst rac-ethylene bis-indenyl zirconium dichloride (rac-(Et[Ind] 2 ZrCl 2 )) with different comonomer ratios. The results of incorporation and catalytic activities obtained with this system were compared with those obtained with ethylene-propylene-1-hexene and 1-decene terpolymers synthesized in the same conditions.…”