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Flame-retardant (FR) cotton fabrics were successfully prepared with the reactive product of (3-piperazinylpropyl)­methyldimethoxysilane and phytic acid, denoted as GPA, through a quick dip-coating technology. The structure, surface micromorphologies, thermal degradation properties, flame retardancy, and combustion properties of samples were assessed. GPA was successfully deposited on the surface of cotton fabrics, which was proved by the results of Fourier-transform infrared analysis as well as scanning electron microscopy coupled with energy dispersive spectrometry (SEM–EDS). During a vertical burning test, FR cotton-3, with an increased mass of 14.33 wt %, immediately extinguished after removing the igniter, while the control was entirely burned. The deposition of GPA to create flame-retardant cotton fabrics led to the serious decrease of heat release rate and total heat release. The promoted flame retardancy resulted from the formed thermally stable residues on the surface of cotton fabrics, which held back mass/heat transfer. Thermogravimetric analysis coupled with Fourier-transform infrared analysis (TG–FTIR) results indicated that flame-retardant cotton fabrics released more nonflammable gases (H2O and NH3) and less flammable gases than the control. According to the results of TG–FTIR, SEM–EDS, and X-ray photoelectron spectroscopy, the mechanism of the flame retardancy of GPA on the cotton fabrics was proposed.

Three novel, environmentally friendly, flame-retardant adhesives (FRAs), i.e., (1) poly-N-β-(aminoethyl)-γaminopropyltrimethoxysilane [P(NTMS)], (2) P(NTMS-phosphoric acid) [P(NTMS-PA)], and (3) P(NTMS-phosphorous acid) [P(NTMS-POA)], are synthesized via a versatile sol−gel method. The chemical structures are characterized by FTIR and 1 H NMR. The thermal stabilities of the FRAs are revealed by thermogravimetric analysis (TGA) and they exhibit single, double, and triple degradation processes, respectively. Flame-retardant expanded polystyrene foams (EPSFs) are prepared with these novel environmentally friendly FRAs by a simple coating method, and their flammability is investigated by limiting oxygen index (LOI), UL-94 vertical burning test, and cone calorimeter (CC). With as high as 57 wt % of P(NTMS) coating, the foam gains no rating in the UL-94 test. In contrast, EPSF with 57 wt % of P(NTMS-PA) coating passes the UL-94 V-0 grade with a LOI of 31%, and the foam with only 40 wt % of P(NTMS-POA) also passes the UL-94 V-0 grade with a LOI of 26.5%. CC results demonstrate that 40 wt % of P(NTMS-PA) coating reduced the peak heat release rate (PHRR) of EPSF by 62.1% and increased the residue from 0 to 36.2%. For P(NTMS-POA), the corresponding values are 68.8% and 34.0%, respectively. The morphology of the residues was revealed by SEM, and the corresponding chemical compositions and carbonaceous structure were studied by FTIR, EDX, and Raman spectra. These results indicated a synergy in charring among phosphorus, nitrogen, and silicon, and the resulting protective layers were responsible for the higher fire safety.

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Fully bio-based EP thermosets from epoxidized soybean oil and tannic acid were prepared for versatile applications under moderate curing conditions.