Classification of water-based polyurethane — divided by appearance

Water-based polyurethane can be divided into polyurethane emulsion, polyurethane dispersion, and aqueous polyurethane solution. The most practical applications are polyurethane emulsions and dispersions, collectively referred to as water-based polyurethane or polyurethane emulsions.

Polyvinylidene chloride resin (PVDC) Polyvinylidene chloride resin, also known as polyvinylidene chloride resin, vinylidene chloride resin, molecular formula (Cz Hz Ch), relative molecular weight is 20000~1000000, polyvinylidene chloride resin is difficult to burn , Its burning flame is yellow, and the ends are green. The density (30℃) is 1.7~1.875g/cm, the softening point is 185~200℃, the decomposition temperature is 210~225℃, and the chlorine content is 72%. Due to the symmetry of the molecular structure, it has a high degree of crystallinity, a relative density of 1.70g/cm (film 1.68g/em, fiber 1.75g/cm), water absorption <0.1%, and PVDC has very low resistance to many gases and liquids.

Transmittance is its biggest feature. This characteristic is made up of the high density and high crystallinity of its molecular structure. In terms of heat, the thermal decomposition of PVDC proceeds in two steps: first, conjugated double bonds are formed, and then carbonization. The heat shrinkage rate is large, and it decomposes to generate Cl or HCl under the action of heat, ultraviolet, ion radiation (a-ray, y-ray), alkaline medium, catalytic metal or salt, and is insoluble in general solvents at room temperature. It has the advantages of not being corroded by bacteria and insects, can withstand a variety of solvents, and is easy to swell in oxygen-containing and chlorinated solvents. The product structure has two forms: original state water glue emulsion and dry resin powder. It is non-flammable and non-toxic. It extinguishes after leaving the fire, softens when burned, expands when carbonized, and releases toxic monomers and hydrogen chloride when it is decomposed.

Polyvinylidene chloride resin is mainly used as a base material (binder) and flame retardant in fireproof coatings. After film formation, it has low permeability, low air permeability, oil resistance and good coating gloss. Therefore, the fireproof coating also has the properties of moisture-proof, water-proof and anti-corrosion. The prepared fire-retardant liquid is used to treat the surface of flammable fiber materials such as wood, polytetrafluoroethylene powder msds wood products, paper, cardboard, and fabrics, and the fiber materials after the treatment are changed from flammable materials to flame-retardant materials.

Tris(2-chloroethyl) phosphate Tris(2-chloroethyl) phosphate, also known as tris(2chloroethyl) phosphate, molecular formula CeH1zOChaP, relative molecular weight 285.50, tris(2-chloroethyl) phosphate It is light yellow oily liquid. Soluble in alcohol, ketone, ester, chloroform, carbon tetrachloride and other solvents, but insoluble in aliphatic hydrocarbons. Water solubility (20℃) 4.64%, boiling point (1.33kPa) 194℃, viscosity (20℃) 34~47mPa·s, freezing point -64℃, thermal decomposition temperature 240~280℃, good hydrolytic stability, in sodium hydroxide A small amount of decomposition in aqueous solution.