Halogenated aliphatic hydrocarbon

A halogenated aliphatic hydrocarbon refers to a derivative in which a hydrogen atom in an open-chain hydrocarbon is substituted with a halogen element, that is, a fluoro, chloro, bromo or iodo derivative. According to the hydrocarbon group structure, it can be classified into a saturated halogenated hydrocarbon (halogenated alkane) and an unsaturated halogenated hydrocarbon (such as a halogenated alkene). According to the number of halogen atoms contained in the molecule, it is classified into a monohalogen, a dihalogen and a polyhalogen. The physical and chemical properties of each derivative vary widely. At normal temperature, generally lower halogenated hydrocarbons (C1 to C4) are gases, higher halogenated hydrocarbons (>C16) are solids, and the middle is liquid. When the halogenated hydrocarbon molecule is the same as the hydrocarbon group, the specific gravity and boiling point of the chlorinated hydrocarbon are the lowest, and the iodohydrocarbon is the highest. If the halogen is the same, the boiling point increases as the molecular weight increases. Most halogenated hydrocarbons are insoluble in water and are readily soluble in organic solvents. Halogen is a functional group of a halogenated hydrocarbon whose chemical activity is mainly determined by a halogen atom. Generally, a carbon-halogen bond is more reactive than a carbon-carbon bond or a carbon-hydrogen bond, is easily broken, and has a nucleophilic property. In addition, the activity of a halogen atom in a halogenated hydrocarbon is also strongly related to the structure of the group directly attached thereto. Haloalkanes are quite active compounds. Some of the halogen atoms in the halogenated olefin are very reactive and some are inactive, and their activity depends on the position of the halogen and the double bond. In terms of biological activity, brominated hydrocarbons and iodohydrocarbons are more toxic than chlorinated hydrocarbons: fluorohydrocarbons are chemically stable and less toxic, but there are exceptions. Most of the halogenated hydrocarbons commonly used in the industry are volatile liquids. Most halogenated hydrocarbons are non-flammable and not explosive. Often used as a solvent, chemical raw material or intermediate, and widely used in agriculture, medicine and light industry.