Preparation Of Core-shell Flame Retardant And Its Application On Silk And Cotton Fabrics

Phosphorus and nitrogen-containing core-shell flame retardant was prepared by semi-continuous seeded emulsion polymerization and was used for flame retardant finishing of silk and fabrics.the influence of different factors on the emulsion polymerization and flame-retardant of cotton and silk fabrics was disscussed in this paper.Firstly,core-shell emulsion was prepared using alkoxy-substitutedhen cyclotriphosphazene acrylates and methyl methacrylate(MMA)as a core phase,butyl acrylate(BA)as shell phase.Optimum factors were obtained from observing the results of emulsion appearance,calcium(ion)stability,storage stability,viscosity,particle size and particle size distribution,solids content and thermal analysis.The prepared emulsion had obvious blue light,good calcium(ion)stability and storage stability,moderate viscosity and surface tension and the solid content reached 16.5%.The prepared latex particle size was about 200 nm,the distribution was concentrated and had clear core-shell structure.Secondly,the synthetic core-shell flame retardant was used for flame retardant finishing of silk and fabrics.The ultimate oxygen index,vertical burning,strength and whiteness were taken as reference indexes to discuss the optimum technological conditions.It was found that the oxygen index of the silk and cotton fabrics finished under the best technological conditions were 28.7% and 27.5% respectively;the length of the vertical burning damage was 122 mm and 128 mm respectively;the flame burning time and smoldering time were both 0s.The tensile strength and the whiteness of the finished fabric aft decreased.It can be seen that the surface of silk and cotton fabrics after finish were covered with a dense polymer film from the infrared spectra and the photographs of scanning electron microscopy(SEM)and atomic force microscope(AFM),The result of micro-calorimetric analysis and thermogravimetric analysis showed that the thermal stability of the silk and cotton fabrics after finish was improved and the heat release amount was reduced,which further proved that the finished silk and cotton fabrics had good flame retardancy.