Commonly used environmentally friendly flame retardants- part 2
With the increasing awareness of global safety and environmental protection, people's requirements for fire safety and product flame retardancy are becoming higher and higher. Halogen-free, low-smoke and low-toxic environmentally friendly flame retardants have become the goals that people are pursuing. Today I will introduce you to several common environmentally friendly flame retardants.
Commonly used environmentally friendly flame retardants
1. Environmentally friendly bromine flame retardant
1. Decabromodiphenylethane 8010
8010 is not a polybrominated diphenyl ether, and it is impossible to produce pbdd or pbdf during combustion; the relative molecular weight of 8010 is 971; the bromine content is 82%, which is equivalent to the bromine content of dbdpo (83%), so the flame retardant performance is basically the same; The melting point is 345℃, and the thermal stability is higher than that of dbdpo (305℃). Its light resistance and dialysis resistance are superior to dbdpo. The valuable thing is that its flame-retardant plastics can be recycled. This is the reason for many brominated flame retardants. Features not available. The 8010 industrial product is a white crystalline powder with an average particle size of 3 μm, free flowing, and micro-granulated. It is easily dispersed in plastic modification and the color of plastic products is free. Moreover, the industrialization cost is equivalent to dbdpo, and it is an ideal substitute for dbdpo.
As an added brominated flame retardant, 8010 also needs to be used with antimonide in the process of use, and the mixing ratio is the same as the ratio of dbdpo/antimonide; compared with dbdpo, 8010 is more suitable for engineering plastics with high temperature and high viscosity characteristics.
2. Brominated epoxy resin
Brominated epoxy resins for flame retardants are also called tetrabromobisphenol a epoxy resin oligomers. The bromine content can reach 50% and the molecular weight is between 1000 and 45000. They are divided into ep type and ec type; ep type and Compared with the ec type, the former has better light resistance, but the bromine content is lower, while the latter flame retardant abs and hips have better impact strength. The commercial brominated epoxy resin is a mixture of cream-colored semi-transparent wafers and white powder. The domestic brominated epoxy resin has a pungent odor, while the Israeli Dead Sea bromine products are odorless. Brominated epoxy resin has satisfactory melt flow rate and high flame retardant efficiency, excellent thermal stability and light stability, and can give the flame retardant substrate good mechanical properties, the product does not frost.
Low phase molecular weight brominated epoxy resins are suitable for flame retardant abs and hips, high phase molecular weight ones are suitable for flame retardant abs/pc alloys and pc, pet, pbt and other engineering plastics. It needs to be used in conjunction with antimony compounds during use.
3. Brominated polystyrene
The development of brominated polystyrene is similar to brominated epoxy resin, and it is also a fast-growing flame retardant variety in recent years. Brominated polystyrene is white or light yellow powder or granules with a bromine content of about 60%. Thermal decomposition temperature is greater than 310 ℃, has the advantages of large molecular weight, good thermal stability, good dispersibility and compatibility in polymers, easy processing, and no frost.
Brominated polystyrene is named brominated polystyrene and polybrominated styrene according to their synthetic routes. From the naming, it can be seen that brominated polystyrene is completed by brominating polystyrene; polybromine The styrene is obtained by first protecting the styrene by ethylenic bond, then brominating, and then recovering the ethylenic bond, synthesizing brominated styrene, and polymerizing again.
Whether a solvent is used in the synthesis process can be divided into a solvent method and a non-solvent method. Because the solvent method consumes less bromine, people usually use the solvent method for synthesis.
Brominated polystyrene is mainly used in thermoplastic resins such as pa, pbt, pet, etc. The use process needs to be used in conjunction with antimony compounds. For flame-retardant polyester, the amount of 13% (reinforced) ~ 17% (non-reinforced) can be assigned to the material ul94v-o grade (0.8mm), and for flame-retardant polyamide, the amount can be assigned to 21% Material ul94v-o grade (0.8mm).