[en] Highlights: • Melamine reacted with sodium tri-polyphosphate, the product MTP was used as flame retardant. • By 10% adding of MTP, butyl acrylate (BA) coating achieve self-extinguish. • By 10% MTP, heat and smoke release of BA coating was reduced by 38.3% and 27.8%, respectively. • By 10% MTP, the water absorption of BA coating was reduced by 37.3%. In order to guarantee fire safety and water resistance of the butyl acrylate (BA) coating, an integrated intumescent flame retardant (IFR) was fabricated. At first sodium tri-polyphosphate (STPP) was selected as acid source, and melamine (MEL) was gas source. STPP and MEL were connected by ionic bond. In the obtained product of melamine tri-polyphosphate (MTP), the amounts of hydrophilic groups was obviously reduced. BA coating containing 10 wt% MTP showed 37.3% reduction on water absorption, and the surface looked smoother with little folds. The limiting oxygen index (LOI) of BA coating is 22%; comparatively, LOI for BA/10 wt% MTP increased to 27%. The heat release rate (HRR), smoke production rate (SPR), CO production rate decreased by 20.1%, 5.4% and 33.3% respectively. The flame retardancy mechanism was tried to deduce by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) observation. It was proposed that MTP promoted the formation of compact char and the release of nonflammable gases.