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New magnetic forms of C60 have been identified which occur in the rhombohedral polymer phase. The existence of previously reported ferromagnetic rhombohedral C60 is confirmed. This property has been shown to occur over a range of preparation temperatures at 9 GPa. The structure is shown to be crystalline in nature containing whole undamaged buckyballs. Formation of radicals is most likely due to thermally activated shearing of the bridging bond resulting in dangling bond formation. With increasing temperatures this process occurs in great enough numbers to trigger cage collapse and graphitization. The magnetically strongest sample was formed at 800 K, and has a saturated magnetization at 10 K, in fields above 3 kOe, of 0.045 emu g-1.

This paper describes the synthesis and the biodegradation of optically active copolymers, poly[(R)-1-methyltrimethylene carbonate-co-ε-caprolactone] and poly[(S)-1-methyltrimethylene carbonate-co-ε-caprolactone] and poly[(R,R)-1,3-dimethyltrimethylene carbonate-co-ε-caprolactone] and poly[(S,S)-1,3-dimethyltrimethylene carbonate-co-ε-caprolactone]. The copolymers were prepared using a novel organolanthanide or AlEt3−H2O as the polymerization initiators, and their biodegradation by various enzymes and acclimated activated sludges was studied as a function of their composition, stereochemistry, crystallinity, T g (glass transition temperature), T m (melting point), molecular weight, and polydispersity. The copolymers synthesized exhibited high molecular weights with rather narrow molecular weight distributions and produced thermoplastic films when (R)-1-MTC (1-MTC = 1-methyltrimethylene carbonate) or (R,R)-1,3-DTC (1,3-DTC = 1,3-dimethyltrimethylene carbonate) content is less than 50 mol %. Optically active and racemic copolymers prepared using 1-MTC/CL (CL = ε-caprolactone) ratios of 17/83 to 19/81 were effectively biodegraded by lipoprotein lipase, cholesterol esterase and activated sludge. For the copolymers prepared using various 1,3-DTC/CL ratios, the poly(rac-1,3-DTC-co-CL) was biodegraded faster than the poly[(R,R)-1,3-DTC-co-CL] and poly[(S,S)-1,3-DTC-co-CL] copolymers regardless of the 1,3-DTC/CL ratio. Biodegradation of all of these copolymers generated numerous cavities on the outermost surface of polymer films or solid masses without changing their molecular weight and polydispersity.

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