• Overview
  • Compounding Information
  • Application

Chemical Name

2, 2, 4-trimethyl-1, 2-dihydroquinoline (oligomers).  (TMQ-High Purity)

Chemical Structure

CAS Reg. No.


Mol. Wt.

(ca) 500

Product Specification



Test Method

Product form




Light Brown


Softening Point (B & R), °C



Heat Loss, % (max)


D 4571

Ash Content, % (max)


D 4574

Bis Aniline, % (max)


NOCIL 01-3-327

Monomer Content, % (max)


NOCIL 01-3-323

Typical Data

Specific gravity at  25°C


D 1817

Bulk density , kg/m3

610 - 650


Alkalinity Index


NOCIL 01-3-326

Ethanol Insoluble’s, % (max)


NOCIL 01-3-328

Product Information                                


Soluble in acetone and alcohol; Insoluble in water.



Discoloration & Staining

Moderately staining & discoloring.

FDA Approval Status

Prohibited for use in articles in contact with food under FDA 21 CFR 189.200,   and regulated as specified under BgVV  XXI, Category 4.

Toxicity Data
(Please refer to the latest
Toxicological information.)

Slightly harmful by mouth. (Oral LD50rat 2250 mg/kg).
Degree of toxicity may differ according to molecular weight.
Not a skin irritant or sensitizer but a slight eye irritant.   

Handling & Personal Protection

Ensure good ventilation and avoid creating dusty atmosphere.  In case of eye or skin contacts wash out with clean water for 5 to 10 minutes. 


Always store in a cool & dry place in single stack pallets away from direct sun light or any other heat source to avoid compaction.


Paper Bag

 20 kg


500 kg

Storage Life

24 months when stored as stated above.

Color code

Black strip.

Trimethyl-Dihydroquinolines (TMQs) function as primary antioxidants and are widely used in rubber compounds based on highly unsaturated rubbers to protect the rubber articles from oxidative degradation at ambient as well as higher temperatures. TMQs represent a group of antioxidants based on polymerized Aniline-Acetone condensation products. The individual products differ by the degree of polymerization and the Dimer, Trimer & Tetramer contents. Thus the composition, molecular weight distribution and performance as antioxidant of TMQ vary from supplier to supplier.


Pilnox TDQ-HP is a specially purified grade of TMQ antioxidant which is almost free from the objectionable impurities such as monomer and primary amine terminated impurities and has been developed for use in specialty applications requiring trouble-free continuous processing & product fabricating operations and high product service performance.


It is well known that only the secondary aminic groups ( = N–H ) function as antioxidants by the formation of  nitroxyl  radical ( - NO ) and thus only  the Dimer, Trimer & Higher oligomers in TMQ act as effective antioxidants for rubbers. The primary aminic groups (- NH2 ) do not function as antioxidants. The primary amine impurities in TMQ antioxidant, such as; 2,2-bis(4’-amino-phenyl) propane (bis-aniline A), 3-(4’-aminophenyl) terminated TMQ, 6-(4’-aminophenyl) terminated TMQ also differ considerably from supplier to supplier.

The primary aminic groups are responsible for:

  • Bluish colored blooming on uncured stock , activation of sulphur cross linking and thus initiating scorch,
  • Destabilization of Insoluble Sulphur by decreasing its transition temperature to soluble Sulphur and thus causing scorch & sulphur bloom problems resulting in the loss of surface tack of the uncured rubber compounds.
  • Dramatically decreasing the ‘peptization’ activity of NR based compounds. This results in the increased stock viscosity at processing temperatures which causes increase in the processing temperature, scorching, porosity, loss of surface tack etc.

High proportions of monomer content in TMQ antioxidant is also considered as an objectionable impurity since it is leached out in water and can cause porosity in thicker cross section extrudates.

Pilnox TDQ-HP is widely used in the manufacture of Truck & Bus Radials, Passenger Radials, OTR tyres, Steel cord conveyor belts and other technically sophisticated rubber products.


Please refer to the table for Pilnox TDQ.

Awards / Certifications