Nonequilibrium morphology

It becomes apparent that under pol)merization conditions a single type of equilibrium morphology may not always be likely. The competition between phase separation and the second-stage pol)merization kinetics can generate nonequilibrium morphologies due to the diffrisional resistance provided by the high local viscosity. In such cases, particles with occlusions or multiple surface domains (lumps) may coexist. 

Several other machines of this type have been developed since. They all involve intensive mechanical shearing that produces extensive chain scission. Recombination of the free radicals in situ generates sufficient concentration of copolymer, to compatibilize the system. The generated-under-high-stress, nonequilibrium morphology is then locked by quenching. Best performance has been observed for systems with co-continuous morphology. 

Physical compatibilization that generates fine, nonequilibrium morphology and locks it by nucleated crystallization. The process may be carried out in the molten or solid state. 

Recently, the multiple morphologies of block ionomers in solution have been investigated extensively (99-101). The equilibrium, near-equilibrium, and nonequilibrium morphologies observed to date are spheres, rods, bicontinuous rods, bilayers, lamellae, vesicles, inverse bicontinuous rods, large compound micelles, aggregates of spheres, large rod-shaped compound micelles, large compoimd vesicles, and many others (101). 

Solution casting of BCP films usually leads to quenching of nonequilibrium morphologies that depend on film thickness, solvent evaporation, and substrate type. In addition to temperature annealing, solvents and solvent vapors were employed as effective tools to enhance equilibration of BCP morphology... 

Phase transition occurs at a state of thermodynamic equilibrium, inducing a change in the microstructure of atoms. However, corrosion is a typical nonequilibrium phenomenon accompanied by diffusion and reaction processes. We can also observe that this phenomenon is characterized by much larger scales of length than an atomic order (i.e., masses of a lot of atoms), which is obvious if we can see the morphological change in the pitted surface. 

A brief review is given of the important qualitative features of thermoplastic elastomers. Particular emphasis is given to the molecular structure, bulk morphology and interfacial character of these materials. Both equilibrium and nonequilibrium structures are discussed... 

The aim of fusion and controlled solidification of a catalytic material is the generation of a metastable catalytic material. The thermodynamic instability can be caused by a nonequilibrium composition, by a non-equilibrium morphology, or by a combination of both. In the case of the SLP catalysts the desired effect is to avoid the formation of solidification in order to maintain a structureless state of the active material. 

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