Polymerizations of hexamethylcyclosiloxane catalyzed by metal sulfonate/acid chloride combinations |
| |
| Authors: | Hicham Qayouh Mohammed Lahcini Jean‐Luc Six Hans R. Kricheldorf |
| |
| Affiliation: | 1. Laboratoire de Chimie Bio‐Organique et Macromoléculaire, Faculté des Sciences et Techniques, Avenue Abdelkrim Khattabi, BP 549, 40000 Marrakech, Morocco;2. Laboratoire de Chimie‐Physique Macromoléculaire, Unité Mixte de Recherche Centre National de la Recherche Scientifique–Institut National Polytechnique de Lorraine 7568, Nancy Université, Ecole Nationale Supérieure des Industries Chimiques, 1 rue Grandville, BP 20451, 54001 Nancy Cedex, France;3. Institute für Technische und Makromoleculare Chemie, Bundesstrasse 45, D‐20146 Hamburg, Germany |
| |
| Abstract: | Hexamethylcyclotrisiloxane (D3) was polymerized in bulk at 100°C, and the conversion was monitored by 1H‐NMR spectroscopy. Various metal triflates, which were inactive as neat salts, were combined with chlorosilanes, chlorostannanes, phenyl phosphonyl chloride, and carboxylic acid chlorides, which were also inactive when added alone. Most 1 : 1 combinations proved to produce active catalysts for the ring‐opening polymerization of D3. When the anions of sodium salts were varied alkylsulfonates and the sulfates were more reactive than the triflate. The samarium triflate/diphenyldichlorosilane combination was found to be the most reactive catalyst on the basis of the triflate ions. Regardless of the catalyst combination, the main reaction products in the early stages of all polymerizations were octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5). The polymerization mechanism is discussed. The reactive catalyst combinations also polymerized D4 at 100°C. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 |
| |
| Keywords: | cationic polymerization polysiloxanes ring‐opening polymerization silicones |
|
|
