Unsaturated Polyester Resin (UPR) is widely used in areas such as construction, shipbuilding, automotive, chemical equipment, light industry products, and sports goods. However, these plastics are highly flammable, leading to frequent fires that cause immeasurable damage to both life and property. Hence, adding an appropriate amount of flame retardants to unsaturated polyester resin becomes crucial. Through the addition of composite flame retardants, extensive experiments were conducted to optimize the flame retardant and mechanical properties of unsaturated polyester resin after treatment. This expansion of fire retardant resin broadened its application scope.
There are various types of flame retardants, roughly divided into three categories:
Halogen Flame Retardants that generate hydrogen halide molecules during combustion. Due to the greater weight of hydrogen halide, it covers the surface of high polymer molecules, isolating oxygen and achieving flame retardancy. This category mostly consists of halogenated organic hydrocarbons.
Hydrate-based Flame Retardants that lose crystalline water during combustion, absorbing heat and reducing the temperature of the burning object below its ignition point, thereby achieving flame retardancy. The primary components in this category are aluminum hydroxide and borate.
Char-forming Flame Retardants that create a char layer on the surface of the burning object during combustion, acting as a barrier to air and achieving flame retardancy. The main types in this category are phosphate salts and phosphoric esters.
Each of these three types of flame retardants added to fire retardant resin after treatment has its own advantages and disadvantages. In unsaturated polyester resin, phosphorus, boron, aluminum, and nitrogen-based flame retardants require relatively larger quantities to achieve better flame retardancy effects. However, excessive use of flame retardants significantly affects the mechanical properties of polymers. Halogen-containing flame retardants require less quantity and have a smaller impact on the physical and mechanical properties of polymers, making them more commonly used. Among halogen-containing flame retardants, brominated flame retardants exhibit better effects. Hence, we have chosen bromine-containing DBD substance as the flame retardant for polyester resin. In order to further reduce the quantity of flame retardants, we have added Sb2O3 and ZnO, which synergize and catalyze the effects of DBD, improving the comprehensive performance of the flame retardant.
Extensive experiments indicate that according to the optimal flame retardant formula, adding different quantities of flame retardants into unsaturated polyester resin results in better flame retardancy as the quantity of flame retardants increases after solidification. However, when the quantity of flame retardants exceeds 40%, the mechanical properties of the fire retardant resin significantly decrease. The tensile strength of the fire retardant resin decreases with an increase in the quantity of flame retardants, dropping noticeably when exceeding 40%.
Contact our experts to obtain the best fire retardant resin solution for your needs.