Preparation of melamine–formaldehyde resin grafted by (3‐aminopropyl) triethoxysilane for high‐performance hydrophobic materials

Aiming at meeting the specific market demands and expanding the downstream application of melamine–formaldehyde (MF) resins, a series of (3‐aminopropyl) triethoxysilane (APTES) grafted MF (MF‐Si) resins were synthesized via an effective method that minimized the hydrolysis of APTES and overcame the polarity discrepancy of APTES with MF resin matrix. The structure of MF‐Si resins was characterized by FTIR spectroscopy, Raman spectroscopy, 1H nuclear magnetic resonance (NMR), and solid state 13C NMR. It was found that APTES moieties in MF‐Si materials afforded increased hydrophobicity, water resistance, and the thermal stability was not affected. With the increasing amount of APTES, the water contact angle of MF‐Si films increased from 70.56 to 105.92°and the surface free energy decreased from 46.8 to 23.5 mN/m. The temperature of maximum weight loss rate (Tdmax) of MF‐Si materials decreased slightly from 371.15 to 353.70 °C and the ultimate residual weight of MF‐Si materials increased from 12.51 to 30.04% at 800 °C under N2.