Solids mechanochemistry

The bond dissociation energy is a prime variable in mechanochemistry since it delineates the level of stress a chain can sustain before rupture (Eq. 62). The role of weak bonds in mechanochemistry has been investigated mainly in the solid... 

Braun T, Buvari-Barcza A, Barcza L, Konkoly-Thege I, Fodor M, Migali B (1994) Mechanochemistry a novel approach to the synthesis of fullerene compounds. Water soluble Buckminster fullerene - gamma- cyclodextrin inclusion complexes via solid-solid reaction. Solid State Chem. 74 47-51. 

For the solid-state reaction to take place, the reactants have to be vigorously mixed by applying external mechanical energy. Thus, the sohd-state reaction may be called mechanochemistry. Mechanochemistry has been used mostly for inorganic solids (for example, for alloying, interaction of soft metals with ceramics, activation of minerals for catalysis, and so on) [1,2] and for inor-... 

Nichols, P. J., Raston, C. L., Steed, J. W., Engineering of porous 7C-stacked solids using mechanochemistry. Chem. Commun. 2001,1062-1063. 

Gutman, E.M., Mechanochemistry of Solid Surfaces, World Scientific, River Edge, NJ, 1994. 

V. V. Boldyrev, K. Tkacova, Mechanochemistry of Solids Past, Present, and Prospects, Journal... 

Mechanical activation of mixtures involves the dispersion of solids and their plastic deformation. These processes cause the generation of defects in solids they also accelerate the migration of defects in the bulk, increase the number of contacts between particles, and renew the contacts. All these factors provide chemical interaction between solids initiated by mechanical loading. These factors are the subject of investigations in one of the fields of solid state chemistry, namely, the mechanochemistry of inorganic substances, which is intensively developed. In particular, a large... 

In solid state chemistry, a special term soft chemistry was proposed to describe the methods based on preliminary synthesis of intermediate compounds which are further used to prepare final products [4]. One of the authors of this monograph has introduced the term soft mechanochemistry for mechanochemical reactions with the participation of highly reactive compounds [30]. They include the reactions with the participation of compounds containing oxygen-hydrogen groups as well as other relatively unstable compounds such as peroxides, nitrates, metal carbonates and other reactive compounds. 

Institute of Solid State Chemistry and Mechanochemistry Siberian Branch of Russian Academy of Sciences Novosibirsk. Russia... 

The authors would like to thank the personnel of the Laboratory of Mechanochemical Reactions of the Institute of Solid State Chemistry and Mechanochemistry of Siberian Branch of the Russian Academy of Sciences, as well as of the Laboratory of Industrial Physical Chemistry of Keio University, for assistance in experimental investigations. They particularly thank E. Devyatkina for her help in manuscript preparation. 

The theory of electronic excitation, which occurs during plastic deformation and fragmentation of crystals, is discussed by Molotskii [99]. The mechanochemistry of inorganic solids has been reviewed by Boldyrev et al. [100] with particular reference to the work done in The Institute of Solid State Chemistry at Novosibirsk. The consequences of mechanical activation on the structures and properties of selected spinels have been examined and the rate of the reaction forming barium tungstate investigated. Prospects for the future development of this subject are assessed. 

This chapter dealt with molecular crystals but not with infinitely covalent crystals or polymers, where mechanochemistry (or tribochemistry) occurs upon milling. Covalent bonds are broken in mechanochemistry of crystals and that produces surface plasmas, which can, for example, be used for the mineralization of all organic materials (including TCDD and methane) [109, 110]. An experimentally confirmed prediction is that three-dimensional infinitely covalent crystals (such as Si02, Fe203, glass, ceramics, etc.) are most efficient. Mechanochemical reactions have to be strictly distinguished from pure surface reactions and from solid-state... 

Lehmann drew attention to some features in solid-state reactions, including the curious observations described in 1834 by Faraday, which are now considered as pioneering experimental studies of the structural sensitivity of the dehydration rate of crystalline hydrates. Crystals of easily eroding sodium salts (carbonates, phosphates, and sulphates), stored by Faraday for a few years, did not exhibit any visible deterioration. A fresh scratch on the crystal surface (birth of mechanochemistry) initiated, however, the onset of intense dehydration with a gradual expansion of the erosion zone until it covered the crystal s entire surface. 

Abstract Atomic force spectroscopy (AFM)-based single-molecule force spectroscopy (SMFS) was invented in the 1990s. Since then, SMFS has been developed into a powerful tool to study the inter- and intra-molecular interactions of macro-molecules. Using SMFS, a number of problems in the field of supramolecular chemistry and mechanochemistry have been studied at the single-molecule level, which are not accessible by traditional ensemble characterization methods. In this review, the principles of SMFS are introduced, followed by the discussion of several problems of contemporary interest at the interface of supramolecular chemistry and mechanochemistry of macromolecules, including single-chain elasticity of macromolecules, interactions between water and macromolecules, interactions between macromolecules and solid surface, and the interactions in supramolecular polymers. 

This review is organized on the basis of polymer architecture and highlights its effect on polymer mechanochemistry. The topic is restricted mostly to CST, chain degradation, and activation of mechanophores in dilute solution because more experimental and theoretical literature is available than that relating to the solid state. Solution or solid phenomena in which no CST or mechanochemical reaction occurs are therefore excluded. 

Bulk mechanochemistry. Unlike linear polymers, the activation of mechanophore in nonlinear macromolecules in bulk is almost blank. Recently, May found that polymers with branched architectures activate more slowly than linear counterparts in solution, yet more quickly in solid-state tensile experiments [198]. In the bulk, more factors take part in the chain degradation event, including but not limited to chain entanglements, phase separation, crystallization, and supramolecular interactions. Inspections in this direction can aid the design of mechanoresponsive materials in the solid state. 

There is also continued interest in the systematic placement of reactive groups in the solid such that their chemical reactivities are determined by the reactants spatial relationships.This was the original premise of Schmidt s topochemistry and has important implications in modern solventless ("green") synthesisand even mechanochemistry. For example, work by MacGilliv-ray resulted in the solid-phase photochemical synthesis of paracyclophane 12 by a strategy termed "template switching" (Fig. 

---