Tag: Polyurethane

Toluene Diisocyanate TDI

Posted on by Guilherme Campos

Toluene Diisocyanate (TDI)

CAS:584-84-9

Toluene Diisocyanate  is produced by a 3 step reaction. The first step is the nitration of toluene to obtain dinitrotoluene. Second step is the catalytic hydrogenation of Dinitrotoluene into toluene diamine TDA. Finally, the TDA react with phosgene to produce the TDI.

TDI is commonly sold under 3 different ratio isomeric :

  • TDI 65 : contains 65 % of 2,4 isomer and 35% of 2,6
  • TDI 80 : contains 80 % of 2,4 isomer and 20% of 2,6
  • TDI 100 : contains 99 % of 2,4 isomer

The two principal isomers of TDI are classified as 2.4-toluene diisocyanate and 2.6-toluene diisocyanate.

Toluene Diisocyanate

TDI is used to produce foams for cushioning material, furniture, bedding, seating or as carpet underlay and packaging. TDI is also used in the manufacture of CASE (Coatings, Adhesives, Sealants, Elastomers).

TDI is classified as “very toxic”.

Arpadis is one of the largest chemical distributor in Europe.

Arpadis is handling the storage, transport, export & import formalities of Toluene Diisocyanate globally.

 

Polytetrahydrofuran(PTMEG)

Posted on by Guilherme Campos

PTMEG, Polytetrahydrofuran,

also called poly(tetramethylene ether) glycol or poly(tetramethylene oxide), is a linear diols with formula (C4H8O)nH2O. It can be viewed as a polymer of tetrahydrofuran, or as the polyether derived from 1,4-butanediol.

The product is commercially available as polymers of low average molecular weights, between 250 and 3000 daltons. In this form it is a white waxy solid that melts between 20 and 30 °C. The commercial product can be processed further into polymers with molecular weights of 40,000 and higher.

Production

PTMEG is produced by polymerizing tetrahydrofuran.

 

Uses

The main use of polytetrahydrofuran is to make elastic fibers such as spandex (elastan) for stretchable fabrics and for polyurethane resins. The latter are polyurethane prepolymers dissolved in solvent. They are used in the manufacture of artificial leather. These elastomers are either polyurethanes made by reacting PTMEG with diisocyanates, or polyesters made by reacting PTMEG with diacids or their derivatives.

The polymer is also a starting material for thermoplastic polyurethane, thermoplastic polyesters, polyetheramide and CAST polyurethane elastomers, used for instance in the wheels of roller skates and skateboards.

Arpadis is one of the largest chemical distributor in Europe.

Arpadis is handling the storage, transport, export & import formalities of Polytetrahydrofuran globally.