DMTDA is short name of Dimethyl Thio-Toluene Diamine, a kind of chain extender. The DMTDA is similar to ETHACURE 300. Because of a liquid at room temperature, so the operation has significant benefits. Such as the transfer easier and MOCA solid melting process will be eliminated.
Similarly, the possibility of solidification does not occur in a mixing vessel or mixing machine inside.
Furthermore, it is in a liquid state, allowing operation at a lower temperature than the MOCA. DMTDA equivalent is 107 (like Ethacure 300) compared with MOCA is 133.5, which means that the same given under stoichiometric prepolymer can be reduced 20% by weight of the amount of use.
CAS No.: 106264-79-3
EINECS Number: 403-240-8
Molecular Formula: C9H14N2S2
Molecular Weight: 214.36
|Boiling point, ℃||353|
|Density (g/cm3) at 20℃||1.21|
|Freezing point, ℃||-9|
|Flash point, TCC, ℃||163.4|
|Viscosity,Cps at 20℃||280|
|Equivalent of epoxy resin||53.5|
|Appearance at room temperature||light yellow to amber clear liquid|
|TDA content, %||≤ 1.0|
|Amine value, mgKOH/g||536|
DMTDA is a new type of polyurethane elastomer curing crosslinking agent. There are mainly two isomers, namely a mixture of 2 4— and 2 6 —dimethylthiotoluenediamine (the ratio is about 77-80 / 17-20).
Compared with the commonly used MOCA, DMTDA is a lower viscosity liquid at room temperature. This ETHACURE 300 equivalent has the advantages of being suitable for construction operations at low temperatures and low chemical equivalent.
Diethyltoluenediamine (abbreviation DETDA, trade name ETHACURE-100) and dimethylthiotoluenediamine (abbreviation DMTDA, trade name is ETHACURE-300) are two commonly used liquid amine chain extenders.
DMTDA reacts slowly with prepolymers compared to DETDA. It is used in combination with DETDA to give good surface leveling properties to elastomers. It will not have much impact on mechanical properties.
But because DMTDA contains methylthio (-SCH3) in its molecule. When used outdoors, it is prone to discoloration and yellowing. Therefore, it cannot be used in places that require high color retention.