Studies On Synergistic Flame Retardance Of Potassium 3-(phenylsulfonyl)benzenesulfonate On Polypropylene And Toughening And Strengthening Of The Composites Related

Polypropylene(PP) is widely used, however, it burns very easily with no rating in the UL-94 vertical burning test as well as the low limited oxygen index(LOI) of merely 17-19. Furthermore, its mechanical properties are poor, with the tensile strength of merely 30 MPa or more and low impact strength. As the result, it is of great importance to improve the flame retardance properties and mechanical properties of PP. Compared with the halogen-containing flame retardants, most of the intumescent flame retardants(IFRs) are harmless and environmentally-friendly, with the lower smoke production and the less dripping melt. Nevertheless, the addition amount of the IFRs is large and the flame retardation effect is to be improved. So far, the metal compounds have been widely associated with the IFRs to improve the flame retardation effect. Potassium 3-(phenylsulfonyl) benzenesulfonate(KSS) is widely used in polycarbonates as an efficient flame retardant. In this paper, the effects of KSS and metal sulfates as synergistic flame retardants on PP were studied, and also the mechanical properties of the composites related. Specific researches were as follows:(1)KSS worked as a synergistic flame retardant in the PP/APP/DPER system. Results showed that the flame retardance properties improved first and then deteriorated with the addition of KSS.When the content of KSS was 0.6%, the flame retardance properties were the best. When the content was higher, KSS antagonized ammonium phosphate(APP).(2)To change the KSS-APP antagonism, magenisum hydroxide sulfate hydrate(MHSH) and MSO4(M=Mn2+ and Ni2+) were applied in the PP/APP/DPER/KSS system to do research on the synergistic effect of the main group and transition metal salts on the flame retardance properties.Results showed that all of the metal salts improved the flame retardance effect of the system at the definite extent. When the amount of MHSH was 1%, the flame retardance properties were the best, with the V-0(3.2mm) and V-1(1.6mm) in the UL-94 test and the LOI of 34.9. The difference of the coordination ability, as well as the unique characteristics of the main group and transition metal salts, led to the difference of the best addition of metal sulfates and the best flame retardance properties of the composites related.(3)The miscibility and the mechanical properties of the PP/FR system were improved with the addition of POE, activated CaCO3(a- CaCO3) and PP-g-MAH. Results showed, with the formulation of M3:APP:DPER:KSS:MHSH=80:13.3:6.7:0.6:1.0 and Matix M3 of PP:PP-g-MAH:POE: a-CaCO3=72.67:8.08:14.25:5,the mechanical properties of the system were improved, with the tensile strength of 21.35 MPa, the elongation at break of 380.00% and the impact strength of 40.35kJ/m2. Meanwhile, the flame retardance effect of the system was good, with V-0(3.2mm) in the UL-94 test and the LOI of 30.5.