Preparation of Flame Retardant Materials
- time:
- 2019-05-11
Since the intrinsic flame retardant material does not need further flame retardant treatment, the following contents are for additive flame retardant materials. Flammable materials can generally include thermoplastic resins, thermosetting resins, rubber, coatings, fibers (natural and artificial fibers), wood and so on. The above flammable materials can be modified into flame retardant materials by the following ways.
(1) Thermoplastic resin thermoplastic polyester resin includes common polyolefins, polyesters and polyamides, such as polyethylene, polypropylene, polystyrene, ABS (acrylonitrile-butadiene styrene copolymer), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polycarbonate (PC), nylon 6 and nylon 66. For the above materials, the flame retardant pellets were prepared by melt blending extrusion in screw extruder with corresponding flame retardant additives, and the flame retardant modification was completed. But usually flame retardant additives are targeted, that is, specific flame retardants act on a variety of resins. There are fewer kinds of flame retardants that can be widely used, so it usually needs careful selection, experiment and composite application.
(2) Thermosetting resins include epoxy resin, phenolic resin, polyurethane, unsaturated polyester resin, etc. This kind of resin needs multi-component blending in application. Therefore, flame retardants can be added at the same time and mixed evenly through rapid stirring. After mixing, curing reaction is carried out at a certain temperature. Thermosetting resin materials with flame retardant properties can be formed after curing.
(3) Rubber rubber can be used as wire and cable materials, conveyor belt materials, etc. The flame retardant requirements are very high. Flame retardant rubber is prepared by blending raw rubber, flame retardant and various additives, then plasticizing, blending and vulcanizing to prepare flame retardant rubber materials.
(4) Coatings and coatings are also made by blending of various components. Therefore, when used, flame retardants and their compositions are usually blended with the components forming coatings to form coatings, which are then coated on the surface of materials such as steel or wood structures to form flame retardant coatings.
(5) Fibers include chemically manufactured fibers such as polyester, polypropylene, acrylic and spandex, as well as natural fibers such as cotton and silk fabrics. Chemical fibers can be spun with flame retardant pellets before they are made into fibers. The obtained fibers have flame retardant function. In addition, flame retardant functionalization can also be achieved by post-finishing of fibers and fabrics. Fiber fabrics are impregnated in flame retardant finishing solution. The flame retardant components can be reactive and react with the functional groups on the fibers. The flame retardant structures are bonded to the fibers, and the flame retardant components can also be physically adhered to the fibers. However, the physical adherent flame retardant component has poor washability because of its weak binding force with fibers. It leads to the loss of flame retardant function of fibers after repeated washing.
(6) Wood and wood are flammable materials. However, as a natural material, it has the characteristics of environmental protection, renewability and biodegradability. Fire retardant wood is usually impregnated. That is to say, through high negative pressure, the cracks in wood and the air in the fibre pipeline are extracted, and then the wood is immersed in the flame retardant liquid. The pressure makes the flame retardant ingredients enter the wood interior, and the fire retardant wood material is formed after drying.
