Morphological transitions of spinodal decomposition in confined geometry

Two-dimensional arrays self-assembledviainterference of concentration modulation waves in drying solutions

“…Strong confinement of a solution favours a reduction of structure dimension of spinodal-precipitated polymers. 31 This may also apply in our case to form arrays with much smaller lattices. We have introduced P(NDI2OD-T2) solution (in toluene or 1,2-dichlorobenzene, 2.5 mg/ml) into a space between a Si substrate and a cover plate [glass or polydimethylsiloxane (PDMS)] that were aligned parallel and separated using spacers of various thicknesses to examine the effect of solution confinement (inset drawing of Figure 3D).…”

“…To explain this phenomenon, one can speculate that the front 1DPS is formed from polymer clusters chaining-up along the contact line, a hypothesis that is supported by a morphology study on spinodal-decomposition in a highly confined solution. [31] To verify this hypothesis, we quenched a sample by suddenly flushing away the solution with 2-propanol during 2D PMS pattern growth from its toluene solution ( Figure 3C). It is clear that a chain of "domes" along the contact line forms the front 1DPS in the solution (indicated by a red arrow).…”

Energy Transfer from Poly(Vinyl Carbazole) to a Fluorene‐Vinylene Copolymer in Solution and in the Solid State†

“…This might be the case for PVK and PFO-MEHPV in THF because this is a lower viscosity solvent, and PVK has a longer emission decay. Nevertheless, this interchain donoracceptor process competes with the intrachain energy migration, which is generally faster than the interchain processes (13,15,21,23,35,(38)(39)(40)(41) and strongly dependent on the chain conformations in solution (19,23,24,33,(42)(43)(44)(45)(46)(47)(48)(49). The polymer chain conformation depends on the solvent quality.…”

“…Polymer blends are very convenient systems for addressing the first difficulty because the phase separation process prevents the complete emission quenching of the higher energy component. The quenching processes may follow two types of mechanisms: the nonradiative (Fo¨rster; 12) resonant energy transfer (FRET) from the higher energy emitting material (the donor) to the lower energy component (the acceptor; [13][14][15][16][17][18][19][20][21] and the trivial process (7,22). In the case of FRET, the reason for partial quenching is the distribution of distances between the donors and acceptors, where some donor-acceptor pairs may be at distances longer than the Fo¨rster radius, and there is only a partial efficiency for this process; some donor-acceptor pairs are within the Fo¨rster distance and can be efficiently quenched (15,17,(22)(23)(24).…”

Variety of Ordered Patterns in Donor–Acceptor Polymer Semiconductor Films Crystallized from Solution

“…Research on spinodal precipitation in confined geometry has shown that the size of the precipitated phase decreases with the reduction of spaces. 31 The periodicity of the pattern is self-adjusted by branching, joining, and growth termination to optimize the λ SN value ( Figure S3 ). Branching is a frequently observed process as the film is grown in the direction with gradually narrowed space and the period of structure reduces accordingly.…”