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

Abstract

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, 1 H nuclear magnetic resonance (NMR), and solid state 13 C 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 (T dmax ) 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 N 2 .

Multifunctional Additives for High-Energy-Density Lithium-Ion Batteries: Improved Conductive Additive/Binder Networks and Enhanced Electrochemical Properties

“…NMR spectroscopy was used to clarify monomer peaks or peaks from physically cross-linked dimer or trimer molecules . As can be seen in Figure c, the NMR spectra of the polymer blends in the range of 3.5–9 ppm revealed the coexistence of highly self-aggregated MF copolymer species (∼7.5 ppm) and relatively isolated MF copolymer species (3.5–5 ppm) at room temperature . Changes of the peak shape, as well as chemical shifts, were observed for the melamine backbone (∼7.5 ppm) and terminal −OCH 3 groups of the MF copolymers in time-dependent NMR spectra of the PVDF/MF copolymer blends. − This chemical shift is related to inter- or intrapolymer interactions originating from the dipole–dipole interaction of protons adjacent to 1,3,5-triazine moieties as well as protons in the alkyl chain (involving ether) of the MF copolymers. , However, no peak shift of PVDF as a function of mixing time was observed (Figure S2).…”

High impact strength modified Melamine–Formaldehyde resin with special “building blocks” structure

“…When the temperature is higher than 520°C (the fifth stage), some small molecules were generated, such as HCN, CO, and CO 2 , which was due to the further decomposition of the MF material. [ 1,6,37,38 ]…”

Preparation of poly(melamine‐formaldehyde‐2,2′‐bis(trifluoromethyl)benzidine) high‐performance fibers

“…The possible reason is that the introduced fluorine atom has a high electronegativity, and its C F bond energy (485 kJ/mol) is higher than C O bond energy (326 kJ/mol) and C N bond energy (305 kJ/mol). 16 The conjugated structure of benzene enhances the intermolecular force, thereby effectively increasing the thermal stability of the molecule. 37 So the mass residual rate of MFF-TFMB fibers increases with the increase of TFMB content.…”

“…We has made some progress in the previous research work. 15,16 In view of the insufficient spinnability of the spinning dope, Meng et al 17 used a composite solvent of dimethylformamide (DMF) and H 2 O to improve the spinnability of the MF spinning solution. Under the optimized process conditions, wet spinning and dry spinning were adopted, respectively.…”