Study of Ethylene-Propylene-1-Hexene Co- and Terpolymers Obtained with Homogeneous and Supported Metallocene Catalysts Griselda Barrera Galland, * Joa˜o Henrique Zimnoch dos Santos, Maiara Dall’Agnol, Rubens Bisatto Summary: Ethylene-propylene-1-hexene terpolymers were obtained using three metal- locenic systems: Cp 2 ZrCl 2 , Cp 2 ZrCl 2 directly supported on silica (Cp 2 ZrCl 2 /SiO 2 ) and Cp 2 ZrCl 2 supported on MAO (methylaluminoxane)-modified silica (Cp 2 ZrCl 2 / MAO/SiO 2 ). The results were compared with those obtained with rac-Et[Ind] 2 ZrCl 2 . The best activities were obtained with the Cp 2 ZrCl 2 in the homogeneous form, but the system Cp 2 ZrCl 2 /MAO/SiO 2 afforded also good results. Those systems showed to be able to incorporate enough comonomers, in a randomic way, to give terpolymers with an elastomeric behaviour. Keywords: mechanical properties; metallocene catalysts; NMR; polyolefins; structure-property relations Introduction The metallocenes are single site catalysts. Therefore, they allow a high control of the microstructure of the polymers, such as, narrow molar weight distribution (Mw/ Mn  2), narrow comonomer distribution in copolymerization and they also copoly- merize bulk monomers which do not react with the traditional Ziegler-Natta cata- lysts. [1] The a-olefins produce, in general, a positive effect on the catalytic activity in the copolymerization with ethylene (como- nomer effect). [2] In fact, metallocenes are excellent for copolymerization compared with other catalytic systems. To obtain an ethylene-1-butene copolymer with 0.92 g/cc density it is necessary a molar ratio of C 4 / C 2 ¼ 0.35 with a Ziegler-Natta catalyst, C 4 / C 2 ¼ 0.083 with a chromium oxide catalyst and C 4 /C 2 ¼ 0.02–0.03 with a metallocene catalyst. [3] The copolymerization depends on the catalyst structure: Metallocenes with bridge incorporate more comonomer and produce polymers with higher molecular weight than those without bridge. However, non-bridged metallocenes supported on silica presented much higher catalytic acti- vities than bridged ones. [4] The use of inert supports for metallocene heterogenei- sation is employed to adapt such catalysts to industry (slurry or gas-phase processes), to decrease the amount of MAO, to control polymer morphology and to prevent reac- tor fouling. [5] In previous a work [6] we obtained ethyl- ene-propylene-1-hexene terpolymers with the homogeneous metallocene rac- EtInd 2 - ZrCl 2 and determined the chemical shifts, triads and reactivity ratios by 13 C NMR. In the present work we aim to study the use of supported metallocenic systems to obtain terpolymers, to compare the results with those obtained with homogeneous metallo- cenes and to correlate the molecular structure of the terpolymers with the mechanical pro- perties. The metallocene Cp 2 ZrCl 2 was chosen to support because is the simplest and cheapest one among the non-bridged Macromol. Symp. 2006, 245–246, 42–50 DOI: 10.1002/masy.200651307 42 Instituto de Quı´mica – Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil Fax: (þ55)051 33167304 E-mail: griselda@iq.ufrgs.br Copyright ß 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim