Kristallstruktur, Festkörperpolymerisation und Ionenleitung in Alkalisalzen ungesättigter Carbonsäuren, 2 [1] Untersuchungen an Lithiummethacrylat und Lithiummethacrylattritonmethanolat

Crystal Structure, Solid‐State Polymerization, and Ionic Conductivity of Alkali Salts of Unsaturated Carboxylic Acids, 2 [1]. — Investigations on Lithium Methacrylate and Lithium Methacrylate Tritonmethanolate The structures of lithium methacrylate C 4 H 5 O 2 Li ( 1 ) and the corresponding lithium methacrylate tritonmethanolate C 4 H 5 O 2 Li · 1/3 CH 3 OH ( 2 ) have been determined by singlecrystal X‐ray diffraction. Compound 1 is built up by inorganic layers – a two‐dimensional network of corner‐ and edge‐shared LiO 4 tetrahedra – and organic double layers with a hydrophobic interaction of zipper‐like arranged methacrylate groups. The crystal structure of compound 2 can also be envisaged as a layered structure where „inorganic” and „organic” blocks alternate. Here edge‐ and cornershared LiO 4 tetrahedra extend in zig‐zag chains along [010] which are bridged by carboxyl groups. The compound is an ionic conductor. – In both compounds the distances between the functional groups are too large for a diffusionless topochemical polymerisation. Polymerisation takes place thermally between 200 and 290°C. It can also be induced by UV irradiation in the presence of benzoin.