Coalescence annealing

Most important, of course, are mixing energy and particularly shear. Also very important are melt viscosities of the two polymers, and particularly their viscosity ratio. Processing temperature has a variety of effects. Crystallization is a primary cause of phase separation, not only in single polymers but also in polymer blends. Stretch orientation has major effects on phase morphology. And demixing/coalescence/anneal-ing effects can sometimes reverse these processes. 

Alloy Coalescence annealing Restoration annealing Recrystallisation annealing ... 

The coalescence of Au microcrystal in the islet film occurs during thermal annealing, as well as when the metal concentration is increased. It is probably the coalescence that does determine the above-mentioned loss of Au/ZnO-sensor sensitivity during high-temperature heating operations. 

Figure 7 (a, b, d, and e) shows transmission electron micrographs from Pd-Ag films of comparable weight, prepared and annealed at 400°C, and used once to catalyze the oxidation of ethylene at 240°C (40). The structure of this series of alloy films varied consistently with composition. Silver-rich films (e.g., Fig. 7a, 13% Pd) showed extensive coalescence of the crystallites, while at the other end of the composition range (e.g., Fig. 7e,...

Nanoparticles can be deposited onto a substrate by spin coating or inkjet printing a colloidal solution and can be sintered into a continuous conductive film during the subsequent annealing step. Coalescence of individual... 

Electrical and optical properties as well as adhesion of many metal films including Pt and Au can be markedly improved by annealing at temperatures up to 600°C in air [55]. These changes are probably manifestations of the coalescence of individual islands into a more continuous film. The effects are particularly pronounced for gold, where the resistivity drops by 30-50% and the optical transparency, as shown in Figure 11.3 [55], improves considerably. Similar effects are observed for Pt [55,57],... 

By further controlling the composition of the starting materials, deposition and heating processes, it may be possible to obtain more homogeneous and pure phases of YAP (or YAG) crystalline films coated on alumina core at lower annealing temperatures to avoid forming clusters or coalescing. 

The incorporation of guest molecules can be achieved during their growth or is executed at defect sites and holes via wet chemistry, by surface diffusion and gas-phase transport. Encapsulated fullerenes tend to form chains that are coupled by van der Waals forces. Upon annealing, the encapsulated fullerenes coalesce in the interior of the SWCNTs, resulting in pill-shaped, concentric, endohedral capsules a few nanometers in length [265], The progress of such reactions inside the tubes could be monitored in real time by use of HR-TEM [266],... 

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