Synthesis, formulation, and characterization of siloxane‐modified epoxy‐based anticorrosive paints

Abstract

Diglycidyl ether of bisphenol A epoxy (E) was modified with hydroxyl-terminated polydimethylsiloxane through a ring-opening addition polymerization reaction. The structural elucidation of the siloxane-modified epoxy resin (ES) was carried out with Fourier transform infrared, 1 H-NMR, and 13 C-NMR spectroscopy techniques. The physicochemical characterization of the synthesized resin (ES) was performed with standard methods. E and ES were subjected to paint formulation with the help of a rutile (TiO 2 ) pigment. The formulated paint systems were cured at room temperature with 1,6-diaminohexane (AH) and 1,3-diaminopropane (AP), which were used as curatives. The E-AH, E-AP, ES-AH, and ES-AP paint systems were applied to mild steel strips. The physicomechanical and anticorrosive performance of the coated panels was evaluated with standard methods. The thermal analysis of these E-amine and ES-amine systems was carried out via thermogravimetric analysis. The effects of siloxane incorporation and amine curatives on the coating properties of the paint systems were also investigated. The ES-AP system exhibited good thermal and corrosion stability performance among all the E and ES paint systems.

Toughening of epoxy resin system using a novel dendritic polysiloxane

“…These results indicate that the thermal stability improves as siloxane components are incorporated into the cured networks. 27 This increasing thermal stability may be due to the high thermal stability of the silicon compound and the protecting effect of the silica layer formed during the decomposition process, where silica greatly restrained the oxidation weight loss of the polymeric materials, and resulted in high the residual weight for the polymers at 800 o C. 28 Nevertheless, the decomposition behavior of cured samples in air (Figure 7) follows the two step decomposition mechanism, which is different from that in N 2 ; and the T d 5% and T d 50% of epoxy resin don't increase exactly upon addition of increasing amounts of DPSO100, which may be due to the complex decomposition behavior of cured samples under air atmosphere. Easily obtained from Table II, the T d 5% of the cured samples in air is lower than that in N 2 while the T d 50% in air is higher than that in N 2 , which can be explained that in air, the surface part of the samples can be easily decomposed, resulting in the lower T d 5%, and when the surface part of the samples decomposed into oxides, these oxides can act as a protecting layer for the inside part of the samples, leading to the higher T d 50%.…”

Effect of molecular weight and content of PDMS on morphology and properties of silicone‐modified epoxy resin

“…44 PDMS-epoxy blend is initially immiscible at room temperature; however, chemically bonding of epoxy to the PDMS chain by the reaction between their reactive groups such as hydroxyl (OH) 12,[21][22][23][24][25][26][27]29 , oxirane, 19,30,31 and amine [32][33][34][35][36][37]45 leads to partial compatibilization. The resulted modified epoxy resins are heterogeneous with PDMS-rich domains irregularly dispersed in the epoxy-rich matrix.…”

Morphologies and mechanical and thermal properties of highly epoxidized polysiloxane toughened epoxy resin composites

“…These results indicate that the thermal stability improved as siloxane components were incorporated into the cured networks. 37 This increasing thermal stability may be due to the high thermal stability of the silicone compound and the protecting effect of the silica layer formed during the decomposition process, where silica greatly restrains the oxidation weight loss of the polymeric materials, and results in high the residual weight for the polymers at 800 o C. 38 While T d 50% of HEPSO2-2 is lower than that of the neat epoxy resin. This can be explained that the HEPSO2 decomposed and transferred to the surface of the epoxy resin at the high temperature, in HEPSO2-2 the HEPSO2 content was so small that it could not form protect layer in the surface of the epoxy resin; and the HEPSO2 affected the network of the epoxy resin, which made the decomposition more easily.…”