TINTM (triisononyl trimellitate) is a high-molecular-weight plasticizer for flexible PVC, the triester of trimellitic acid with isononyl alcohol. Compounders use it where the plasticizer has to stay in the part at high temperature, mainly in PVC wire insulation up to the 105 °C class and in automotive interior trim that must not fog the windscreen.
TINTM Chemical Identity
TINTM is triisononyl trimellitate, CAS 53894-23-8, EC 258-847-9, with the formula C36H60O6 and a molecular weight of 588.9 g/mol. It is the triester of trimellitic acid (1,2,4-benzenetricarboxylic acid), made by esterifying trimellitic anhydride with isononyl alcohol, a mixture of branched C9 alcohols.
It is not trioctyl trimellitate. That name and the abbreviation TOTM are used for tris(2-ethylhexyl) trimellitate, a C8 ester with CAS 3319-31-1, so a CoA or SDS carrying that number describes TOTM.
TINTM is also sold under trade names including Jayflex TINTM, ELATUR TM and ADK Cizer C-9N. It is registered under REACH and listed on the US TSCA Inventory.
Key Properties of TINTM
TINTM’s plasticizing efficiency is lower than TOTM’s. At 60 phr it gives a compound of Shore A 87 where TOTM gives 83, so a given hardness takes more TINTM.
Volatility
TINTM is less volatile than TOTM. Over 7 days at 136 °C, a TINTM compound lost 2.81% of its weight and a TOTM compound 3.10%. Over 21 days at 135 °C, in a compound with 50 phr plasticizer, TINTM lost 2.3% and TOTM 13.1%.
The two tests used different formulations, so each pair holds only within its own test.
Migration and Extraction Resistance
TINTM migrates less than half as much as TOTM. Held against rigid PVC at 70 °C for 28 days (DIN EN ISO 177), a compound with 33 phr TINTM lost 2.0% of its weight, against 4.2% with TOTM.
Like other trimellitates, TINTM goes into compounds where water extraction must stay low. For extraction by soapy water, oil or solvent, test the compound in the medium the part will meet.
Heat Aging Performance
TINTM-plasticized PVC keeps most of its elongation through long heat aging. After 21 days at 135 °C, a compound with 50 phr TINTM retained about 88% of its elongation at break, against about 31% for the same compound with TOTM.
Electrical Properties
TINTM gives PVC a volume resistivity of about 10¹⁰ Ω·cm at 70 °C, on a par with TOTM.
What TINTM Is Used For
TINTM goes mainly into PVC wire and cable insulation rated for high temperature and into automotive interior trim. It also appears in sheet, seals and plastisols where the same permanence is needed.
High-Temperature Wire and Cable Insulation
TINTM is used in high-temperature PVC wire and cable insulation because it stays in the compound through the oven aging used to qualify a temperature rating, so the insulation keeps enough elongation to bend without cracking. Under UL, insulation rated 105 °C is aged for 7 days at 136 °C. TINTM is supplied for the UL 105 °C class.
Automotive Interiors
TINTM is used in automotive interior trim, such as instrument-panel skins and seat and steering-wheel covers, because it hardly fogs the windscreen. In the gravimetric fogging test of DIN 75201 (method B, 16 hours at 100 °C), TINTM left 0.20 mg of condensate, against 5.02 mg for DOP.