The so-called bicummyl, is actually an intermediate, or synthetic material intermediate. From the appearance, the bicummyl is usually white or light yellow powder, or flake. When packaging, it can also be 20 kg bags, or 10 kg carton packaging.
The brief introduction of the bicummyl products
The molecular formula of the product is C18H22 and the formula weight is 238. The melting point is 110 - 119 ℃, and the fugitive constituent is not more than 0.5%. In the storage process, the bicummyl should be closed storage, and placed in a dry and ventilated place. Storage temperature should be below 40 ℃. In real life, we also often call it 1,1' - ( 1,1,2,2 - tetramethyl - 1,2 - ethylidene ) diphenyl. Its full name is 2,3 - dimethyl - 2,3 - diphenylbutane.
In contrast, the structure composition of the bicummyl is more special. Because the C一C key between the corresponding quaternary carbon atoms is not stable enough, it is easy to dissociate and form free radicals. At present, the product is mainly applied to flame retardant synergists and crosslinking copolymerization catalysts. Compared with common free radical evocating agents such as peroxides, azoic compound, the bicummyl has high stability and safe use.
In general, the effect of the content of the bicummyl on the tensile strength of the system is not so obvious. However, when the content reaches 1.2 phr, it has good flame retardancy, good tensile property and flame retardancy. In view of the production cost, the addition amount is usually controlled to 1 to 2 phr.
The typical applications of the bicummyl products
When 1.6 % iodobenzene and 0.2 % Sb2O3 are added to polypropylene, if adding moderate bicummyl, the oxygen index of the product is 25.5. If not added, the oxygen index is 19.5. Especially in HIPS formula, the use of this product has a great advantage. Under the condition of ensuring the same flame retardant effect, the use of bicummyl formula can greatly reduce the amount of brominated flame retardant.