Improvement of epoxy resin properties by incorporation of TiO2 nanoparticles surface modified with gallic acid esters

Effect of surface modified TiO2 nanoparticles on thermal, barrier and mechanical properties of long oil alkyd resin-based coatings

“…Modification of TiO 2 NPs with gallates was done according to the procedure described in the literature [38]. The procedure for the surface modification of TiO 2 NPs with lauryl gallate will be briefly described here.…”

“…According to these results, it can be concluded that the coordinative bond between surface Ti atoms and gallate was achieved through the adjacent -OH groups from the benzene ring, by creating bridging complexes, which is in agreement with our previous results [28, LG NPs. Detailed explanation of the FTIR spectra of TiO 2 NPs surface modified with gallates is given elsewhere [38]. FTIR spectra of DHBA, OA, dry TiO 2 colloid and dry TiO 2 -DHBAOA NPs are presented in Figure 4b.…”

“…The first stage of thermal degradation of surface modified TiO 2 NPs occurred due to the mass loss of the absorbed water, while the second stage between 210 and 800°C corresponds to the mass loss of adsorbed ligand grafted on the surface of TiO 2 NPs. In our previous work we have shown that theoretical amount of adsorbed ligand necessary to cover all Ti surface sites should be 1.86 mmol of ligand per gram of TiO 2 [38]. According to the TGA results obtained here, the amount of the adsorbed ligands, TiO 2 -HG, TiO 2 -LG, TiO 2 -CG and TiO 2 -DHBAOA, are 0.90, 0.89, 0.80 and 1.53 mmol per gram of TiO 2 , respectively.…”

“…Alkyd paint prepared using molybdenum oxide (MoO 3 ) NPs showed good antibacterial properties against pathogenic bacteria [37]. In our previous studies, we have synthesized and examined properties of NCs based on epoxy resin and TiO 2 NPs surface modified with propyl, hexyl and lauryl gallate [38], as well as the influence of the size of TiO 2 nanoparticles, their concentration and type of the surface modification on the rheological properties of alkyd resin [28]. Since there is constantly increasing demand for developing environmentally friendly materials and taking into account that alkyd resins are one of the most applied resins and TiO 2 is one of the most applied pigment in coating industry, in the present study we have made an effort to prepare novel alkydbased NCs with improved properties, by utilizing differently surface modified TiO 2 NPs and alkyd resin based on vegetable oil.…”

Synthesis and characterization of the surface modified titanium dioxide/epoxy nanocomposites

“…Aromatic ligands with two or three adjacent phenolic OH groups (catechol, pyrogallol and gallic acid) can be adsorbed on the surface of TiO 2 by forming chelating or bridging complexes with titanium ions on the surface [24][25]. In our previous works, TiO 2 nanoparticles were surface modified with different alkyl gallates [26] and then incorporated into the poly(methyl mehacrylate) and epoxy matrix [27]. The length of the aliphatic part of the used gallates showed a great effect on dispersability of the surface modified TiO 2 nanoparticles and on the properties of both matrices.…”