| Antimony pentoxide colloidal is one of the best varieties in inorganic flame retardants, it is characterized by high dispersion, fine particles, high thermal stability, low smoke, easily dispersed, low price and so used as a flame retardant in various fire-retardant environment. Antimony trioxide as the raw material of this thesis, first at a temperature of 90-95℃prepared the antimony pentoxide hydrosol, then through the modified-extraction method, the antimony pentoxide particles extracted into organic phase, preparation antimony pentoxide organic sol.Electrolyte coagulation experimentally derived the surface of particles exist in the antimony pentoxide hydrosol is negatively charged. Adding different cation surfactants to modification the particles surface, then measuring free energy and settling property of the modified particles surface, obtained that the benzylaminewith higher ionization constant and lower HLB value of the best effect to particles modified. The more addition of benzylamine, the smaller value of particles'γSD/γSP, the longer settling time of modified particles in the carbon tetrachloride solution, the better modification.It was found by exploring, preparation of organic antimony pentoxide sol by modified - extraction process is simple, the Sb2O5 particles of organic sol is small. By this method, using benzylamine as extractant, oleic acid as extraction conditioner, cyclohexanone as the diluent, phase separation will be better with the addition of benzylamine and oleic acid increased; control of stirring speed 400rpm, temperature is 60℃, modify- extract 50mL antimony pentoxude hydrosol with the concentration of 22.2g/(100mL)-1, when benzylamine addition amount is 34.2% of Sb2O5 by weight, oleic acid addition level of 6 times of TEA in the hydrosol by volume, cyclohexanone addition level of 25mL, the extraction rate of Sb2O5 is 96.13%, organic sol viscosity was measured in 1h as 83.8mPa.s, place one year later, organic sol viscosity increased to 99.5mPa.s only; colloidal particle size distribution between the 6～11nm, modified-extraction process without aggregation phenomenon. Modified-extraction temperature can speed up the phase separation rate, but lower extraction rate; stirring speed can improve the extraction rate, stirring speed 400rpm is the most appropriate speed. With the thicken of organic sol, the viscosity increased rapidly, when the concentration reaches 60g/(100mL)-1, the viscosity close to the 300mPa.s. Change the dielectric constant of diluentscan make effect to the modified - extraction process, with the increase of non-polar organic solvents'dielectric constant, the extraction rate increased, phase separation accelerated, but it will increase the viscosity of the organic sol. Diluents on the distribution of particles has little effect.By analyzing the viscosity of diluted epoxy resin, the oxygen index and physical properties of cured epoxy resin, this paper further studed the flame retardant and synergistic effection of antimony pentoxide organic sol on the epoxy resin. Experiments show that the dilution effect and curing effect in the following order variation:Sb2O5 toluene sol> Sb2O5 xylene sol> Sb2O5 cyclohexanone Sol> Sb2O5 cyclohexanol sol> Sb2O5 powder> Sb2O3 powder> Sb2O5 hydrosol; flame retardant as follows sequence variation:Sb2O5 xylene sol> Sb2O5 cyclohexanone sol> Sb2O5 toluene sol> Sb2O5 cyclohexanol sol> Sb2O5 hydrosol> Sb2O3 powder> Sb2O5 powder; organic sol and decabromodiphenyl ether complex with n (Br):n(Sb)=4.5:1, when antimony pentoxide addition is 3phr, the LOI value of epoxy resin increased from 19.8 to 35 or more. |
PDF Full Text Request