The toluene diisocyanate has 2,4-toluene diisocyanates and 2,6-toluene diisocyanate (TDI).

There are two isomers of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate (TDI). According to the content of the two isomers, there are three standard products in the industry: (1) TDI-65 contains 2,4-TDI65%, 2,6-TDI35%; (2) TDI-80 contains 2,4- TDI80%, 2,6-TDI20%, more common; (3) TDI-100 contains 2,4-TDI100%. Carbon dioxide occurs with water effect. Easy to work with compounds containing active hydrogen atoms. Linear polyurethane or polyurethane resin with diol effect.

Miscible with ether, diethylene glycol, acetone, carbon tetrachloride, benzene, chlorobenzene, kerosene and olive oil. It can react with hydroxyl-containing compounds, water, amines and compounds with active hydrogen atoms to generate carbamate, urea, semicarbazide, etc. Toluene is nitrated with mixed acid to obtain 2,4- and 2,6-dinitrotoluene, and then hydrogenated and reduced in the presence of nickel catalyst to obtain 2,4- and 2,6-diaminotoluene, which is then reacted with light in chlorobenzene solution. produced by gas reaction.

Dibenylmethane diisocyanate, referred to as "MDI", is an organic substance, a chemical formula C15H10N2O2.

M-xylene is an organic compound with a molecular formula C8H10, a molecular weight of 106, a colorless concussion liquid, a odor like toluene.

It is a solvent for a variety of coatings and a raw material for preparing dibutyl phthalate, a plasticizer. It is also used in the manufacture of butyl acrylate, butyl acetate, ethylene glycol butyl ether,

Potassium hydroxide is strongly alkaline and corrosive, and its properties are similar to sodium hydroxide, which can cause burns. It can absorb water and dissolve in the air, and absorb carbon dioxide to gradually become potassium carbonate. The pH of the 0.1 mol/L solution is 13.5.

The industrial neighborl xylene is a raw material, first washes the acid layer to the acid layer colorless, then use 10% sodium hydroxide solution, water is washed to pass, and the aqueous layer is separated, and the calcium chloride is borned with anhydrous carbon. After the distinction is low, the intermediate fraction is collected, that is, a pure product.

When the temperature drops to 2.18K, the properties of liquid helium will change suddenly, the viscosity is very small, and it becomes a super fluid that can flow upwards along the wall of the container. The thermal conductivity is 800 times that of copper. It becomes a thermal conductor with excellent thermal conductivity. Its specific heat capacity, surface tension, and compressibility are all abnormal. This abnormal liquid is called liquid helium II, and the normal liquid helium is called liquid helium I.

Appearance and properties: colorless liquid, almost odorless Molecular weight 90.12 Vapor pressure 0.51 kPa/20℃ Flash point: 43℃ Melting point -70°C boiling point: 135.1°C solubility can be miscible with water and most organic solvents such as ethanol Density (D4) 0.925-0.935

From the perspective of physics, the methods to eliminate foam mainly include placing baffles or filters, mechanical stirring, static electricity, freezing, heating, steam, radiation, high-speed centrifugation, pressure and decompression, high-frequency vibration, instantaneous discharge and ultrasonic (acoustic) Liquid control), etc., these methods promote the gas permeation rate at both ends of the liquid film and the drainage of the bubble film to varying degrees, so that the stability factor of the foam is smaller than the attenuation factor, and the number of foams is gradually reduced.

Hydrogen Peroxide Solution is an aqueous solution of hydrogen peroxide.

Phosphorus pentachloride is mainly used as a chlorination reagent for alcohols, carboxylic acids, amides, aldehydes, ketones, enols, and Beckmann rearrangement reagents. It is used as a chlorination agent and catalyst in organic synthesis, and is used in the production of medicines, dyes, and chemical fibers. It is also the raw material for the production of phosphazene chloride and phosphorus oxychloride.

Solubility: Insoluble in water, acid and alkali, but soluble in organic solvents such as alcohol, ether and benzene.The preparation methods of biphenyl include the chemical composition method of making biphenyl through benzene pyrolysis and the separate extraction method of making biphenyl through various coal tar fractions. The mass fraction of biphenyl in coal tar is 0.20%-0.40%, and coal tar extraction method and chemical composition method coexist.

Physical and chemical properties: (1) Melting point (° C): - 2 (2) Boiling point (° C): 158 (no water) (3) Relative density (water = 1): 1.46 (4) Relative density (air = 1): no material (5) Solubility: dissolved in water, alcohol, ether, insoluble in benzene, petroleum ether (6) Stability: unstable, protected from light (7) Preventing the conditions of touch (taboo): strong acid, strong alkali, acyl chloride, alcohol, amine, flammable or combustible materials.

Methyl Isobutyl Ether ether is also known as methyl isobutone, 4-methyl-2-pentanone.

Appearance and traits: white crystals, extremely salty, non -toxic. It is easy to solverate in water, ether, glycerin and alkali, slightly soluble in ethanol, but insoluble in water -free ethanol, which is hygroscopic and easy to lump; New potassium salt is generated by reciprocating and disintegrating.

N-butanol is an organic compound of the molecular formula C4H10O, which has a strong flame when the colorless transparent liquid is combined.

A substance that can reduce the surface tension of water, solution, suspension, etc., prevent the formation of foam, or reduce or eliminate the original foam. [1]