Cyclododecene in Olefin Metathesis: Polymerization and Macromolecular Cross-Metathesis with Polynorbornene
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The reaction of macromolecular cross-metathesis of polynorbornene and polydodecenamer catalyzed by the first-generation Grubbs Ru-carbene complex is studied for the first time. Polydodecenamer with high-molecular-weight characteristics (Mw = 406 × 103, Ð = 2.5) and a yield of 96% is synthesized by the ring-opening metathesis polymerization of cyclododecene mediated by the second-generation Grubbs catalyst. The polymer has a melting temperature of 62–83°C, depending on the content of trans double bonds, and shows poor solubility in organic solvents at room temperature. Its cross-metathesis with polynorbornene at 40°С gives rise to new statistical multiblock copolymers of norbornene and cyclododecene with different degree of blockiness. NMR, GPC, and DSC were used to investigate the effect of reaction conditions on the structure and thermal properties of the copolymers. At the initial step of the reaction, along with a high-molecular-weight peak, the GPC chromatograms exhibit a peak due to the low-molecular-weight fraction (M = (1–2) × 103), suggesting the formation of cyclooligomers. With increasing degree of interchain exchange, the proportion of the oligomeric fraction decreases appreciably. The kinetics of the cross-metathesis of polynorbornene with polydodecenamer and polyoctenamer at 40°С is studied by in situ 1Н NMR spectroscopy and ex situ 13С NMR spectroscopy. The rates of elementary reactions in these blends differ insignificantly, except for the conversion stage of the initial carbenes into polymer ones. The formation rate for carbene [Ru]=polyoctenamer is three times higher than the formation rate for the [Ru]=polydodecenamer carbene. In both cases, the fraction of Ru carbenes attached to norbornene units is extremely small throughout the process.
The structure of the synthesized compounds was studied using equipment of the Shared Research Center of the Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, and the Center for Molecular Composition Studies of the Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences.
This study was supported by the Russian Science Foundation (project no. 17-73-10450).
- 1.V. Sh. Fel’dblyum, Synthesis and Application of Unsaturated Cyclic Hydrocarbons (Khimiya, Moscow, 1982) [in Russian].Google Scholar
- 2.US Patent No. 4.048.262 (1977).Google Scholar
- 3.L. M. Vardanyan, Y. V. Korshak, M. P. Peterina, and B. A. Dolgoplosk, Dokl. Akad. Nauk SSSR 207, 345 (1972).Google Scholar
- 12.C. Gascon, F. Lucas, S. Carlotti, and A. Deffieux, J. Appl. Polym. Sci. 118, 1830 (2010).Google Scholar
- 20.C. Descour, T. Macko, I. Schreur-Piet, M. P. F. Pepels, and R. Duchateau, RSC Adv. 5, 9658 (2015).Google Scholar
- 21.M. L. Gringolts, Yu. I. Denisova, G. A. Shandryuk, L. B. Krentsel, A. D. Litmanovich, E. S. Finkelshtein, and Y. V. Kudryavtsev, RSC Adv. 5, 316 (2015).Google Scholar
- 34.K. J. Ivin and J. C. Mol, Olefin Metathesis and Metathesis Polymerization (Acad. Press, London, 1997).Google Scholar
- 38.V. M. Kuteinikov, Yu. V. Korshak, and B. A. Dolgoplosk, Tr. Mosk. Khim.-Tekhnol. Inst. 86, 117 (1975).Google Scholar
- 43.H. Höcker, L. Reif, W. Reinmann, and K. Riebel, Recl. Trav. Chim. Pays-Bas 96, M47 (1977).Google Scholar