Laser annealing is a competitive alternative to conventional oven annealing of block copolymer (BCP) thin films enabling rapid acceleration and precise spatial control of the self-assembly process. Localized heating by a moving laser beam (zone annealing), taking advantage of steep temperature gradients, can additionally yield aligned morphologies. In its original implementation it was limited to specialized germanium-coated glass substrates, which absorb visible light and exhibit low-enough thermal conductivity to facilitate heating at relatively low irradiation power density. Here, we demonstrate a recent advance in laser zone annealing, which utilizes a powerful fiber-coupled near-IR laser source allowing rapid BCP annealing over a large area on conventional silicon wafers. The annealing coupled with photothermal shearing yields macroscopically aligned BCP films, which are used as templates for patterning metallic nanowires. We also report a facile method of transferring laser-annealed BCP films onto arbitrary surfaces. The transfer process allows patterning substrates with a highly corrugated surface and single-step rapid fabrication of multilayered nanomaterials with complex morphologies.

Mesogenic dibenzophenazine derivatives have been synthesized and their liquid crystalline, fluorescent and electrochemical properties have been studied. All compounds form the Col phase, one of them (4-hydroxyphenyl 2,3,6,7-tetrakisoctyloxy-dibenzo[a,c]phenazine-11-carboxylate, 4) additionally shows an unusual columnar structure with p2mg symmetry, which is a partially lamellarized columnar phase. The emission spectra exhibit a huge Stokes shift that is due to the different molecular conformation in ground and excited states. The non-dispersive hole transport current under UV laser illumination was observed and the charge mobility in the range 10-10 cm V s was determined with the time of flight (ToF) method. The measurements have been interpreted according to the Gaussian disorder model, providing material parameters that reflect the energetic distribution of localized states (diagonal disorder, σ) and distribution of coupling parameters between transport sites (off-diagonal disorder, Σ).

The introduction of new fuels to power internal combustion engines requires testing the compatibility of such fuels with materials commonly used in fuel supply systems. This paper investigates the influence of alternative fuels on the acrylonitrile-butadiene rubber and fluoroelastomer used in the automotive industry. In the study, conventional diesel fuel, its blend with 7% of fatty acid methyl esters and paraffinic diesel fuel produced with the Fisher Tropsch synthesis from natural gas were interacted with the elastomers. The immersion tests were carried out at room temperature (20 °C) for 168 h. The effect was evaluated based on changes in the selected rubber’s volume, mass and hardness. It has been confirmed that the synthetic component without aromatic hydrocarbons had a different effect on the tested rubber than did conventional fuel. In follow-up work, the selected rubbers were also subjected to microscopic observation. The most frequently observed effect was the washing out of the seal protective layer.

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