Smart polymeric coatings for damage visualization in substrate materials

Abstract

For damage indication needs in polymer composites, three smart acrylic coatings based on microencapsulated crystal violet lactone leuco dye with embedded developer silica gel and methyl 4-hydroxybenzoate were elaborated. Damage visualization ability upon duralumin substrates was tested. Indentation tests were conducted in the interval of 0.0005–0.55 J of mechanical work. Digital image analysis was used for evaluation of the visual response in the form of “bruise” spots. The measure of response intensity was relative excess of blue color above achromatic gray in the scanned images of the “bruise” spots. This technique allowed detecting influence of the coating formulations onto the substrate damage visualization.

Preparation of epoxy-acrylate copolymer@nano-TiO2 Pickering emulsion and its antibacterial activity

“…Over the past decades, the unique functions and physiochemical properties of organic/inorganic composite materials make them being widely applied [1][2][3], such as special/smart coatings [4][5][6], environmental remediation materials [7,8], high-temperature superconductors [9] due to the combination of electrical transport [10], magnetic property [11,12] and antibacterial property [13,14] of inorganic nanoparticles and good film-forming ability, good transparency and softness of polymer particles [15,16]. Nano-TiO 2 with self-cleaning property [17], high surface activity [18,19] and low cost [20] is of critical inorganic nanoparticles for development of superior composite materials.…”

Plasmonic‐Based Mechanochromic Microcapsules as Strain Sensors

“…Recently, more direct and efficient techniques for the visual detection of deformations have been developed. These methods are based on the use of dye molecules, which are either encapsulated, crosslinked with the polymer matrix, or incorporated as simple additives within the polymer matrix . However, in many of these cases, the mechanochromic efficiency of the dispersed dyes depends on many factors including the type of polymer matrix, external parameters such as the temperature, an optimal phase separation between the dyes and the polymer host, and on the concentration of the dyes themselves …”

Self‐Reporting Fiber‐Reinforced Composites That Mimic the Ability of Biological Materials to Sense and Report Damage

“…To achieve this effect, pH differences between the dye solution in the capsules and the bulk polymer can be exploited, very similar to the classic working principle of carbonless copy paper . For example, Vidinejev et al encapsulated crystal violet lactone and dispersed the capsules together with the developers methyl 4‐hydroxybenzoate or silica gel into an acrylic resin . When bruised, the colorless leuco dye switched to its blue form in the acidic environment provided by the developers.…”