Flame retardance and thermal properties of a novel phosphorus-containing unsaturated polyester resin/SiO2 hybrid nanocomposite

Abstract

A novel phosphorus-containing unsaturated polyester resin/SiO 2 hybrid nanocomposite was prepared from the in-situ curing of unsaturated polyester resin (UP) and triethoxysilane (DI) which was synthesized from the nucleophilic addition reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) and 3-(trieoxysilyl) isocyanate(icteos). The formation of unsaturated polyester resin/SiO 2 hybrid nanocomposite (UP-DI) was confirmed by infrared spectra (FTIR) and scanning electron microscopy (SEM). With the increase of DI contents, the limiting oxygen index (LOI) value of the cured UP-DIs was raised from 19 to 29, suggesting a significant improvement in flame retardance. The improved flame retardance could also be revealed by the variations of weight and morphology of char residues. Thermogravimetric analysis (TGA) both in air and in nitrogen was used to estimate mechanism of thermal degradation and activation energy (E a ) of different degree of conversion (α) was calculated by Ozawa's method. The UP-DI containing 10%DI (UP-DI10) had higher E a than the pure UP as α>5% because the degradation mechanism was altered by the incorporation of DI.

Preparation, Flame Retardancy, and Thermal Degradation of Unsaturated Polyester Resin Modified with a Novel Phosphorus Containing Acrylate

“…9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and its derivatives, as a novel kind of phosphorus-containing flame retardants, have attracted considerable attention due to their high reactivity. Although DOPO has been widely used as an effective flame retardant for some polymer matrix, such as Epoxy, PET, and PC, − only a few attempts to introduce DOPO into UPR have been described in the literature. , …”

A new type of unsaturated polyester resin with epoxy functionalized nano‐silica and dimer fatty acid: Preparation and property

“…Rusmirović et al 1 modified UPR using gas‐phase SiO 2 and found that with only 1.0 wt% SiO 2 , the glass transition temperature, tensile modulus, and Shore D hardness of the material increased by 10.71%, 16.63%, and 22.44%, respectively. Zhang et al 28 prepared SiO 2 /UPR hybrid material using the in‐situ polymerization method. The flame retardant performance of the material was significantly improved, which indicates that SiO 2 was an effective polymer filler.…”