Nanoscale polymer blend surface

PS was directed to hydrophobic ODT areas and the negatively charged PAA was directed to the positively charged MUAM area. In conclusion, chemically patterned surfaces were shown to be successful in directing the assembly of a polymer blend solution into nanoscale structures. 

J. H. Wei, D. C. Coffey, D. S. Ginger, Nucleating pattern formation in spin-coated polymer blend films with nanoscale surface templates. J. Phys. Chem. B, 2006, no, 24324. 

Apart from the use of block copolymers providing nanoscale features other methodologies alone or in combination can provide hierarchically stmctured patterns. For instance taking advantage of the template assisted stmcturation, demixing of polymer blend solutions on stmctured substrates can also be employed to create multiscale ordered surfaces. Boneberg et al. [202] employed this approach and blended two components, PVP and PS, already known to form ordered porous films during phase separation [203]. The authors used a micrometer patterned... 

An application outside of packaging for nanoscale platelets to impart barrier resistance to a polymer blend is in preventing undesirable small molecule (plasticizer) migration to the surface. As in aU applications, the clay particles should be dispersed to the highest degree possible without losing aspect ratio, even if it means only including them in one phase of the blend. 

Scanning electron microscopy (SEM) is one of the very useful microscopic methods for the morphological and structural analysis of materials. Larena et al. classified nanopolymers into three groups (1) self-assembled nanostructures (lamellar, lamellar-within-spherical, lamellar-within-cylinder, lamellar-within-lamellar, cylinder within-lamellar, spherical-within-lamellar, and colloidal particles with block copolymers), (2) non-self-assembled nanostructures (dendrimers, hyperbranched polymers, polymer brushes, nanofibers, nanotubes, nanoparticles, nanospheres, nanocapsules, porous materials, and nano-objects), and (3) number of nanoscale dimensions [uD 1 nD (thin films), 2 nD (nanofibers, nanotubes, nanostructures on polymeric surfaces), and 3 nD (nanospheres, nanocapsules, dendrimers, hyperbranched polymers, self-assembled structures, porous materials, nano-objects)] [153]. Most of the polymer blends are immiscible, thermodynamically incompatible, and exhibit multiphase structures depending on the composition and viscosity ratio. They have two types of phase morphology sea-island structure (one phase are dispersed in the matrix in the form of isolated droplets, rods, or platelets) and co-continuous structure (usually formed in dual blends). 

In this chapter, the application of secondary ion mass spectrometry (SIMS) techniques, and in particular of time-of-flight secondary ion mass spectrometry (ToF-SIMS) and nanoscale secondary ion mass spectrometry (NanoSIMS), to polymer surface characterization is presented, with attention focused especially on polymer blends and interfaces. 

Luminescent and electroluminescent polymer blends are interesting alternatives for production of efficient organic devices [5,13,244,245,247,250-256]. Kim and coworkers fabricated polymer LEDs based on poly(2,7-(9,9-di- -octylfluorene-a/t-benzothiadiazole)) (F8BT) and poly(2,7-(9,9-di-n-octylfluorene)-a/t-(l,4-phenylene-((4-iec-butylphenyl)imino)-l,4-phenylene)) (TFB) polymer blends as the emissive layer [252,257], Their studies on the phase separation of these blends [258] evidenced a micron-scale lateral phase separation with a nanoscale vertical phase segregation due to the enrichment of the lower surface energy component (TFB) at both air and substrate interfaces. The use of this blend as an emissive layer enhanced the device performance. 

D visualization of bicontinuous morphologies in block copolymer systems has been achieved [26-27] by TEMT (see Sect 2.2). This technique affords the real-space structural analysis of complex nanoscale morphologies without a priori synunetry or surface assumptions [97]. Application of numerical methods developed [39, 98] to measure interfacial curvatures from 3D LSCM images of SD polymer blends (see Sects. 3.2.3 and 4.3.3) to a TEMT reconstruction of the G morphology yields the first experimental measurements of interfacial curvature distributions, as well as (H) and an, in a complex block copolymer nanostructure. 

AFM is used at the nanoscale to analyze structure of polymers. It has been used to determine spatial distribution of impact modifier in high impact polypropylene (95), follow pit growth in a film of a blend as a function of exposure time during degradation studies of coatings on metal (96), determine surface topography and molecular organization of liquid crystalline polymers (97), and observe... 

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