N,N-DIMETHYL-p-TOLUIDINE

N,N-DIMETHYL-p-TOLUIDINE

CAS No: 99-97-8 

EC Number: 202-805-4

Synonyms: N,N-DIMETHYL-p-TOLUIDINE; N,N-Dimethyltoluidine; Benzenamine, N,N,4-trimethyl; N,N,4-Trimethylaniline; Dimethyl-4-toluidine; p-Toluidine, N,N-dimethyl-; p-(Dimethylamino)toluene; 4,N,N-Trimethylaniline; dimethyltolylamine; 1-(Dimethylamino)-4-methylbenzol; 4,N,N-Trimethylaniline; 4-Dimethylaminotoluene ; N,N,4-Trimethylaniline ; N,N-Dimethyl-4-methylaniline ; 4-(Dimethylamino)toluene; DMPT; N-DMPT

Chemical formula: 4-(CH₃)C₆H₄N(CH₃)₂

Molar Mass: 135.21 g/mol 

Hill Formula: C₉H₁₃N

HS Code: 2921 43 00

Specifications

Assay (GC, area%): ≥ 98.5 % (a/a)

Density (d 20 °C/ 4 °C): 0.935 – 0.937

The curing of unsaturated polyester resins at ambient temperatures can generally not be performed by an organic peroxide alone. 

The radical formation, which is necessary to start the polymerization reaction, is at ambient temperatures with most generally applied organic peroxides too slow.

To speed up the radical formation in a controllable way, organic peroxides must, therefore, be used in combination with a so-called accelerator N,N-Dimethyl-p-toluidine.

N,N-Dimethyl-p-toluidine is a polymerization catalyst for polyesters, acrylate, and epoxy resins. 

N,N-Dimethyl-p-toluidine is also used as a hardener for dental cement and in adhesives. 

N,N-Dimethyl-p-toluidine serves as an intermediate for photographic chemicals, industrial glues, artificial fingernail preparations, colorants, and pharmaceuticals. 

N,N-Dimethyl-p-toluidine reacts with vinyl ether in the presence of copper(II) chloride, giving tetrahydroquinolines. 

Further, N,N-Dimethyl-p-toluidine is used to accelerate the polymerization of ethyl methacrylate.

N,N-Dimethyl-p-toluidine is used as an accelerator in preparing dental materials and bone cement to activate the polymerization reaction or when curing methyl methacrylate monomers. 

The concentrations in these preparations are usually between 0.5% and 3% (NTP,2012). 

N,N-Dimethyl-p-toluidine has been used in acrylic denture materials for 50 years (HSDB, 2015). 

In addition, N,N-dimethyl-ptoluidine is an essential ingredient of industrial glues and artificial fingernail preparations when short setting times are needed and is also used as an intermediate in the manufacture of dyes and pesticides.

Applications: Engineered Stone, Pultrusion, Resin Transfer Molding, Filament winding, Chemical anchors & mine bolts, Hand lay-up & spray-up, pH regulators and water treatment products, leather treatment products, adhesives and sealants, coating products, laboratory chemicals, washing & cleaning products and textile treatment products and dyes, dental adhesives.

Physicochemical Information of N,N-Dimethyl-p-toluidine:

Boiling point: 215 °C (1013 hPa)

Boiling point: 211 °C (HSDB, 2015)

Density: 0.88 g/cm3 (35 °C)

Density (at 20 °C): 0.94 g/cm3 (IFA, 2015)

Flashpoint: 76 °C

Flashpoint: 83 °C (IFA, 2015)

Ignition temperature: 425 °C

Melting Point: -15 °C

Melting point: −15 °C (IFA, 2015)

pH value: 7.44 (H₂O, 25 °C)

Vapor pressure: 0.099 hPa (20 °C)

Solubility: 0.65 g/l

Octanol/water partition coefficient (P):

log Kow, 2.81 (HSDB, 2015)

Volatility: Vapour pressure, 0.01 kPa [0.178 mm Hg], at 20 °C (IFA, 2015)

Vapour density: 4.66 (air = 1) at 20 °C (IFA,2015)

Solubility: Insoluble to moderately soluble in water (650 mg/L at 37 °C) (ECHA, 2015)

Solubility: Miscible with alcohol, ether, and chloroform.  Immiscible with water.

Stability: Lower explosion limit, 1.2 vol. %; upper explosion limit, 7.0 vol. % (IFA, 2015)

Ignition temperature: 425 °C (IFA, 2015)

Conversion factor (at 101 kPa, 20 °C): 1 ppm = 5.62 mg/m3 (IFA, 2015)

Toxicological Information

LD 50 oral: LD50 Rat 1650 mg/kg

Production of N,N-Dimethyl-p-toluidine

(a) Production methods

Multiple methods exist for the manufacture of N-alkyltoluidines, including N,N-dimethylp-toluidine, such as acid-catalyzed alkylation of unalkylated 

toluidines with lower unbranched alcohols or ether. 

Another method involves reductive alkylation with lower aldehydes or ketones using metal catalysts under hydrogen pressure (Bowers, 1996).

N,N-Dimethyl-p-toluidine is stable at ambient temperatures.