TPU (Polyurethane elastomer)

TPU (thermoplastic polyurethane elastomer) is an emerging plastic variety, because TPU has good processability, weather resistance, environmental protection, is widely used in footwear, pipe, film, roller, cable and wire and other related industries.

Polyurethane thermoplastic elastomer, also known as thermoplastic polyurethane rubber, referred to as TPU, is A (AB) N-type block linear polymer, A is a high molecular weight (1000-6000) polyester or polyether, B is a diol containing 2-12 straight chain carbon atoms, the chemical structure between AB segments is diisocyanate, usually MDI connection.

Thermoplastic polyurethane rubber is cross-linked by intermolecular hydrogen bonds or slight cross-linking between macromolecular chains. With the increase or decrease of temperature, these two cross-linking structures are reversible. In the molten state or solution state, the intermolecular force is weakened, and after cooling or solvent volatilization, there is a strong intermolecular force connected together to restore the performance of the original solid.

Polyurethane thermoplastic elastomers are polyester type and polyether type two types, white irregular spherical or columnar particles, the relative density of 1.10-1.25, polyether type relative density is smaller than polyester type. The glass transition temperature of polyether type is 100.6-106.1℃, and the glass transition temperature of polyester type is 108.9-122.8℃. The brittleness temperature of polyether type and polyester type is lower than -62℃, and the low temperature resistance of hard ether type is worse than that of polyester type.

Polyurethane thermoplastic elastomers are characterized by excellent wear resistance, excellent ozone resistance, high hardness, high strength, good elasticity, low temperature resistance, good oil resistance, chemical resistance and environmental resistance, and the hydrolysis stability of polyether ester in wet environment is far more than that of polyester type.

Polyurethane thermoplastic elastomer is non-toxic, odorless, soluble in methyl ethyl ligand, cyclohexanone, tetrahydrofuran, dioxane, dimethylformamide and other solvents, can also dissolve in toluene, ethyl acetate, butyl ketone, acetone in the appropriate proportion of the mixed solvent, colorless and transparent state, has good storage stability.

PU (Polyurethane)

PU polyurethane is a general term for polymer compounds formed by the reaction of diisocyanate or polyisocyanate with more than two hydroxyl groups, and its main chain contains many repeated NHCOO groups. Commonly used diisocyanates are toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexyl diisocyanate (HDI), isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (HMDI), polymethylene polyphenyl polyisocyanate (PAPI), benzene dimethylene diisocyanate (XDI) and so on.

According to the different hydroxyl components used, it can be divided into polyester type and polyether type. It can be used in the manufacture of plastic manufactures, wear-resistant synthetic rubber products, synthetic fibers, hard and soft foam products, adhesives and coatings.

TPU and PU are essentially made up of the same material. But when you're making these two kinds of glue. They don't use the same formula. These two kinds of rubber materials are divided into many kinds of properties. The characteristics of the rubber compound made by different formulas are not the same. These properties refer to both mechanical and physical properties.