Thermal stability and mechanical properties of room temperature vulcanized silicone rubbers

摘要

Based on much of the importance of RTV on the field of self-cleaning application for its nontoxic, tasteless, and thermal stability, the effects of D _4-SiO _2 on mechanical properties, Al(OH) _3 and decabromodiphenyl oxide ethyl(DBDPE) on flame retardant property of RTV matrix were investigated firstly. Then, a new kind of complex fire retardants was compounded. The morphology of additives and fracture appearance of composites were demonstrated by SEM. The hot property of RTV-based composites was outlined by TG. It is found that D _4-SiO _2/Al(OH) _3/DBDPE/ Sb _2O _3/RTV composites were of better comprehensive performances in mechanical property, hot property, fire resistance property, and insulating property, which presented tear 26.73 kN/m of strength, 279.8% of elongation at break, 2.81 MPa of tensile strength, FV-0 at the level of flame retardant property, 46 of Oxygen index (OI) 3.03 × 10 ~(15) Ωm of Volume electric resistivity, the range of decomposition temperature was 370°C to 650°C, and the percentage of remain weight was 26.4%. Those properties was acquired on the condition of 11 wt % D _4-SiO _2 + 20 wt % Al(OH) _3 + 15 wt % DBDPE+ Sb _2O _3 at the amount of 3.0 wt % to 3.7 wt %. This investigation leads the authors to a conclusion that D _4-SiO _2/Al(OH) _3/DBDPE/Sb _2O _3 is a kind of better combination modifier than anyone kind of which in comprehensive properties for RTV.