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The effect of microencapsulation of dihydrogen ammonium phosphate (MAP) in the generation of fire-resistant coatings was studied in the presence of tannins extracted from Pinus radiata. MAP was encapsulated to avoid interaction with sodium carbonate (Na2CO3), which, upon contact with fire, generates unwanted gases. Thus, a fireproof (or intumescent) protective film was produced in the presence of the tannins. Microcapsules were polymerized with melamine and characterized by Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), and scanning electron microscopy (SEM)-Energy-Dispersive X-ray Spectroscopy (EDS). The microcapsules were spherical with diameters between 0.7 and 1 µm. The as-produced microcapsules were mixed with tannin extract and the properties of their films were evaluated on wood and structural steel substrates; their fire resistance on medium density fiberboard was also evaluated. Flame resistance tests showed a carbonization index of 26.86% using microcapsules (3% w/w); this is better than commercial coatings. The film properties were similar to commercial coatings, but the adherence was slightly decreased due to agglomeration and also film flexibility.

Poly(butylene adipate‐co‐terephthalate) (PBAT) was mixed with copper nanoparticles (Cu‐NPs) in concentrations of 1%, 3%, and 5% with particle size between 100 nm and 200 nm by the melting method. A morphological, thermal, and structural characterization of the nanocomposites (NCs‐PBAT/Cu) was performed to analyze the effect of the Cu‐NPs on the polymer chains, as well as to explain the influence on their crystallinity, and its influence on the thermomechanical and antibacterial properties. The percentage of crystallinity (Xc) increased 6.7% to 9.5% with the amount of Cu‐NPs in the matrix. E‐modulus was slightly improved from 84.04 to 87.7 MPa, in the same way the degradation temperature (Td) of the PBTA was improved from 420.7°C to 427.2°C for 5% loading of Cu‐NPs. In contrast, ΔHm decreased from 12.50 to 6.96 J/g, indicating that there was no significant modification of the PBAT chain, mainly by heterogeneous nucleation in the presence of Cu‐NPs, which act as a heat barrier. No blue or red shifts we observed in the nanocomposites Fourier transform infrared (FTIR) spectra, indicating there is no effective interaction between PBAT and Cu‐NPs. The nanocomposites showed excellent antibacterial properties inhibiting 100% of the strains Enterococcus faecalis, Streptococcus mutans, and Staphylococcus aureus, at 2 hours of treatment. For more resistant strains such as Acinetobacter baumannii, the NCs‐PBAT/Cu did not show antibacterial activity at any time of treatment. POLYM. COMPOS., 40:1870–1882, 2019. © 2018 Society of Plastics Engineers

The objective of this study was to examine the combined protection effect of a two-layer system consisting of organic corrosion inhibitors (tannins derived from the bark of radiata pine) and anodic protection by means of the incorporation of zinc oxide nanoparticles modified superficially by chemical methods to improve the protection of metallic structures against corrosion. Film evaluations are performed in accordance with ISO and ASTM standards. This study also took into account the evaluation of the performance of two commercial coatings according to the scheme suggested by the supplier, in addition to the electrochemical impedance spectroscopy (EIS) characterizations at 0 h, 720 h of accelerated exposure, and 4 months of atmospheric exposure in a corrosive environment of classification C3. The results obtained indicated that the combination of tannins derived from pine bark and encapsulated zinc oxide nanoparticles is a viable alternative to commercial coatings with a higher concentration of synthetic compounds. Although the film properties decrease slightly, performance tests at different exposure times show that they can still be classified as high-performance coatings.

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The effect of microencapsulation of dihydrogen ammonium phosphate (MAP) in the generation of fire-resistant coatings was studied in the presence of tannins extracted from Pinus radiata. MAP was encapsulated to avoid interaction with sodium carbonate (Na 2 CO 3 ), which upon contact with fire, generates unwanted gases. Thus, a fireproof (or intumescent) protective film was produced in the presence of the tannins. Microcapsules were polymerized with melamine and characterized by FTIR, TGA, SEM-EDS. The microcapsules were spherical with a diameter between 0.7 and 1 µm. The as-produced microcapsules were mixed with tannin extract and the properties of their film were evaluated on wood and structural steel substrates; their fire resistance on medium density fiberboard was also evaluated. Flame resistance tests showed a carbonization index of 26.86% using microcapsules (3% w/w); this is better than commercial coatings. The film properties were similar to commercial coatings, but the adherence was slightly decreased, due to agglomeration and also films flexibility.Surfaces, Interfaces and Coatings Technology 4 www.videleaf.com