Spin-cast polymer blend films

S. Y. Heriot, R. A. L. Jones, An Interfacial Instability in a Transient Wetting Layer Leads to Lateral Phase Separation in Thin Spin-Cast Polymer-Blend Films. Nat. Mater 2005,4,782-786. 

Budkowski A, Bemasik A, Cyganik P, Raczkowska J, Penc B, Bergues B, et al. Substrate-determined shape of free surface profiles in spin-cast polymer blend films. Macromolecules 2003 36 4060-7. 

Heriot S Y, Jones RAL. An interfacial instability in a transient wetting layer leads to lateral phase separation in thin spin-cast polymer-blend films. Nat Mater 2005 4 782-6. 

Raczkowska J, Budkowski A, Rysz J, Czuba P, Lekka M, Bernasik A. Effect of diblock copolymers on the film stmcture of spin cast polymer blends. J Nanostruct Polym Nanocompos 2005 1 23-33. 

One extensively studied material system among the nanocrystal-polymer blends is zinc oxide (ZnO) in combination with MDMO-PPV or P3HT [273-282]. Beek et al. presented the first polymer solar cells containing ZnO nanoparticles, reaching power conversion efficiencies of 1.6% [273]. In this case the nanoparticles were prepared separately and then intermixed with MDMO-PPV in solution. Shortly after this study the Janssen group presented another route to ZnO-polymer hybrid solar cells by forming the nanocrystals in situ inside the film by applying a precursor [274]. Here, diethylzinc served as the precursor and was spin cast in blends with MDMO-PPV. Process-... 

Zink et al. used a blend of polystyrene (hPS) and its deuterated counterpart (dPS), both of molecular weight 1.95 x 106 (abbreviated 1.95 M). The average volume fraction (4>dPS) of deuterated polystyrene was 30%. The polymers were dissolved in toluene and spin cast on thin silicon wafers (about 10 x 10 mm), the resulting film thickness being about 300 nm. The samples were annealed at 245°C for 8 days, and the measurement of the resulting depth profiles was conducted by NRA using a monoenergetic 700 keV 3He beam. The nuclear reaction employed can be written ... 

Nonconjugated poly[l,3-propanedioxy-l,4-phenylene-l,2-ethenylene(2,5-bis(tri-methylsilyl)-l,4-phenylene)- l,2-ethenylene-l,4-phenylene] (DSiPV) and conjugated MEH-PPV polymers are mixed by changing their weight ratios in 1,2-dichloroethane. The films of the blend polymers could be spin-cast from 1,2-dichloroethane solution with excellent reproducibility. AFM (atomic force microscopy) and SEM images show no indication of phase separation or layer formation due to the immiscibility of two polymers. The structures of DSiPV and MEH-PPV are shown in Fig. 24. 

The LED structures consist of an aluminum rectifying contact on the blend polymers which have been spin-cast onto ITO glass as a hole-injecting contact. The film thickness ranged from 60 to 80 nm. The electron-injecting aluminum contacts are deposited by vacuum evaporation at pressure below 10 6 torr, giving active area of 0.195 cm2. 

Fig. 51 Preparation of the pristine polymer and polymer-polymer blend nanoparticles is presented. Step 1 a by ultrasonication a polymer solution and water/surfactant solution are blended to a miniemulsion and transformed by solvent evaporation to an aqueous polymer-in-water nanoparticle dispersion. Step 2 b Films are spin cast from the dispersion. (Reprinted with permission from [239], 2003, Macmillan Publishers Ltd)...

Kim J-S, Ho PKH, Murphy CE, Friend RH (2004) Phase separation in polyfiuorene-based conjugated polymer blends lateral and vertical analysis of blend spin-cast thin films. Macromolecules 37 2861... 

In typical work of Yu et al. [29], the arrays were fabricated on ITO glass substrates. The ITO glass layer was patterned by photolithography into perpendicular rows of electrode strips (width 450 pm, spacing 185 pm). The polymer film, a blend of poly(3-octyl thiophene) and fullerene PCBM[6,6] (see Section 6.3), was spin-cast onto the substrate. 

J.-S. Kim, P. K. H. Ho, C. E. Murphy, R. H. Friend, Phase Separation in Polyfluorene-Based Conjugated Polymer Blends Lateral and Vertical Analysis of Blend Spin-Cast Thin Films. Macromolecules 2004,37,2861-2871. 

Information on short-distance spatial proximity between different segments of molecules can be obtained using the proton spin-diffusion NMR method. This is a particularly valuable method for the characterization of polymer blends. For example, in case of PS/PVME cast films, the method provided information on blend composition, fraction of interacting groups (phenyl from PS with ether from... 

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