A novel fluorinated thermoplastic (FT) was synthesized from diglycidyl ether of bisphenol A (DGEBA), and 3-(trifluoromethyl)aniline. FT was found to be miscible with DGEBA as shown by the existence of a single glass transition temperature (T g ) within the whole composition range. On the basis of several experimental techniques, it was found that upon heating etherification reaction takes place between FT and DGEBA. A DGEBA-aromatic diamine (4,4 0 -methylenebis(3-chloro 2,6-diethylaniline) formulation was modified with the FT. The influence of FT on the epoxy-amine kinetics was investigated. Both structural parameters, gelation, and vitrification, were found to be affected by etherification reaction between epoxy and hydroxyls groups belonging to FT. The presence of ether linkages induced system stoichiometry modification. In addition, the curing conditions influence on FT migration towards the surface was studied on samples prepared with 20 wt % of modifier. SEM-EDX analysis confirmed that modified systems exhibits notable fluorine enrichment within the uppermost 200 lm.

HIGHLIGHTS  Epoxy resin was microencapsulated by in situ polymerization in oil-in-water emulsion.  Poly(urea-formaldehyde) was selected as shell material.  Several reaction conditions were analyzed.  Lyophilized microcapsules resulted in stable free flowing powders.  Microcapsules were strong enough to bear the manufacturing of a composite material.

Summary: Fluorinated polyurethane films were obtained from 5‐isocyanato‐1‐(isocyanatomethyl)‐1,3,3‐trimethyl‐cyclohexane (IPDI) and polyethylene oxide (PEO), employing two monoalcohols with different chain lenghts as fluorinated modifiers, 1H,1H,2H,2H‐tridecafluoro‐1‐n‐octanol (EA600) and 1H,1H,2H,2H‐heptadecafluoro‐1‐n‐decanol (EA800). X‐ray photoelectron spectroscopy (XPS) has demonstrated that fluorine surface enrichment takes place. Atomic force microscopy (AFM) was employed in order to characterize films surfaces, in terms of topography and differences in hydrophobicity from light and moderate tapping conditions.

Halloysite nanotubes (HNTs) have attracted a technologic and scientific attention as reinforcements of epoxy-based nanocomposites. However, their reported interaction with epoxy matrices is varied and the controlled dispersion of HNTs is still a challenge. In this work, we study the effect of chemical reactions taking place in the dispersion process of halloysite and their possible influence in the composite's properties. HNTs' surface was modified through an alkaline treatment and by grafting two aminosilanes with different chain lengths and functionality numbers. Evidence of homopolymerization and degradation reactions was found, depending on the surface treatment. The rheological study indicated that an interconnected network can be achieved in epoxy/HNTs blends depending on the surface chemical characteristics of the nanofillers and the blending method. The better dispersion was accomplished when ultrasonicating with the aid of a solvent. Nevertheless, the mechanical properties of the nanocomposites are not warranted by selecting a dispersion method.During the last decade, scientists and engineers have discovered and developed a large range of exciting new applications for these unique, cheap, and abundantly available naturally occurring clays. 17,18 Regarding the production of reinforced polymers, one key factor needed to obtain a composite material that successfully fulfill the required service life performance, is to control nanofiller dispersion and nanofiller/matrix interaction. Due to their lower number of surface hydroxyl groups, it is expected that HNTs will disperse better than other silicates such as montmorillonite and kaolinite. It is reported that HNTs can be dispersed quite uniformly by a direct melt-blending Additional Supporting Information may be found in the online version of this article.

The influence of the surface chemical modification on the bulk behavior of epoxy based networks has been studied. In particular, the bulk dynamics of epoxy-amine networks modified with fluorinated side chains has been characterized by means of broadband dielectric spectroscopy (BDS), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The fluorination effect on the structure and dynamics of the materials has been related with the observed changes in both segmental and secondary relaxations. An acceleration of the segmental dynamics as the fluorination degree increases has been clearly observed. As a result, a compromise between fluorine surface enrichment and bulk modification has been proposed for these materials.

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Two series of trifluoromethylated crosslinked epoxy‐based polymers with different molecular architectures and fluorine contents (from 1 to 5 wt%) have been investigated. The epoxy monomer was a diglycidyl ether of bisphenol A, and the curing agents were 3‐(trifluoromethyl)aniline and 4,4′‐methylenebis(3‐chloro‐2,6‐diethylaniline). The structural parameters of networks such as gelation and vitrification and the properties of the resulting fluorinated materials were investigated and compared. Final materials showed high transparency with an ultraviolet‐visible absorption cut‐off between 350 and 380 nm, low moisture (0.60 wt%) and a decrease in dielectric constant from 6.3 to 5.2 with increasing fluorine content. Copyright © 2012 Society of Chemical Industry