 |
| "Synonyms:TMA 1,2,4-Benzenetricarboxylic acid 1,2-anhydride 1,2,4-Benzenetricarboxylic anhydride 1,3-Dioxo-1,3-dihydro-2-benzofuran-5-carboxylic acid Anhydrotrimellitic acid 4-Carboxyphthalic anhydride Molecular Formula:C9H4O5 Molecular Weight: 192.13 HS Code: 2917399090 Grade: Industrial grade98.40% Hazard Class:General Cargo" | |||||||||
552-30-7
bosschemical
552-30-7
1. Product Overview
Trimellitic anhydride (TMA; 1,2,4-benzenetricarboxylic anhydride; C₉H₄O₅, CAS 552-30-7) is a white crystalline aromatic anhydride carrying one anhydride ring and one free carboxylic acid group — the specialty intermediate behind some of the most demanding polymer applications in industry. Its largest commercial use is the manufacture of trimellitate plasticizers for poly(vinyl chloride): high-molecular-weight triesters that keep flexible PVC soft, stable and low in volatility at high service temperatures, making them the standard plasticizers for wire and cable insulation, automotive upholstery, gaskets and other high-temperature plastics. TMA is also an important curing agent for epoxy resins, a monomer in poly(amide-imide) and poly(ester-imide) resins used for heat-resistant electrical insulation, and a building block of water-based and solvent-based alkyd/polyester coating resins, dyes and printing inks. it must be handled only with full industrial-hygiene controls. As a manufacturer we supply consistent, well-documented product with COA .
Core value propositions:
● High-Performance PVC Plasticizer Intermediate (Core Application): trimellitate esters for wire & cable, automotive and high-temperature PVC;
● Epoxy Curing Agent & Heat-Resistant Resin Monomer: poly(amide-imide), poly(ester-imide), alkyd and coating resins;
● Tricarboxylic Functionality: one anhydride plus one free carboxyl for branched, high-performance polymer chemistry;
● Documented Quality & Compliance: COA with every batch; full SDS; EU SVHC (respiratory sensitizer) handling guidance.
2. Product Information (Quick Facts)
Item | Specification |
Chemical Name | Trimellitic anhydride (1,2,4-benzenetricarboxylic anhydride; 1,3-dioxo-2-benzofuran-5-carboxylic acid) |
Synonyms | TMA; TMAN; anhydrotrimellitic acid; 4-carboxyphthalic anhydride; trimellitic acid 1,2-anhydride |
CAS No. | 552-30-7 |
EC No. (EINECS) | 209-008-0 |
Molecular Formula | C₉H₄O₅ |
Molecular Weight | 192.13 g/mol |
Appearance | Colorless to white crystalline solid (needles) |
Solubility | Reacts with water (hydrolyzes to trimellitic acid); < 1 mg/mL in water at 20 °C; soluble in polar organic solvents |
3. Chemistry & Structure
Trimellitic anhydride, C₉H₄O₅ (MW 192.13), is the 1,2-anhydride of 1,2,4-benzenetricarboxylic (trimellitic) acid: a benzene ring bearing two vicinal carboxyl groups fused into a five-membered anhydride ring plus a third free carboxylic acid. This dual functionality — a reactive anhydride plus a free acid — makes it a versatile branching monomer and crosslinker: with alcohols it forms the triester trimellitate plasticizers used in high-temperature PVC; with amines and diacids it builds poly(amide-imide) and poly(ester-imide) chains for heat-resistant electrical insulation; and with epoxy resins it acts as an anhydride curing agent. The molecule hydrolyzes in contact with water to regenerate trimellitic acid, so the material must be kept dry. It is produced industrially by the oxidation of pseudocumene (1,2,4-trimethylbenzene), typically by liquid-phase air oxidation, and is a white crystalline solid melting at 165–169 °C with very low vapor pressure.
4. Key Features & Benefits
● Trimellitate plasticizer route: the key intermediate for high-temperature, low-volatility PVC plasticizers (wire & cable, automotive, gaskets).
● Dual functionality: one anhydride plus one free carboxyl — branching and crosslinking chemistry for resins.
● Epoxy curing agent: well-established anhydride hardener for high-performance epoxy systems.
● Heat-resistant resin monomer: poly(amide-imide) and poly(ester-imide) for electrical insulation.
● Coatings building block: water-based and solvent-based alkyd/polyester paint resins.
● Consistent quality: controlled assay, acid value and melting point with COA.
5. Main Applications
5.1 Trimellitate Plasticizers for PVC (Core Application)
The largest amount of trimellitic anhydride is used to make plasticizers for poly(vinyl chloride) (Ullmann's):
● High-molecular-weight trimellitate esters: plasticizers with very low volatility.
● Wire & cable insulation: flexible PVC that retains performance at high service temperatures.
● High-temperature plastics: automotive upholstery, gaskets and heat-exposed flexible PVC parts.
5.2 Epoxy Resin Curing Agent
● Anhydride curing agent for epoxy resins: crosslinked, high-temperature-capable epoxy systems.
● Electrical and electronic applications: cured epoxy with good dielectric and heat performance.
● Formulated epoxy systems: hardener component for coatings, adhesives and composites.
5.3 Poly(Amide-Imide) & Poly(Ester-Imide) Resins
● Monomer for poly(amide-imide) and poly(ester-imide) resins.
● Heat-resistant electrical insulation: wire enamels and magnet-wire insulation.
● High-temperature engineering applications of imide polymers.
5.4 Coatings, Alkyd & Polyester Resins
● Polyester resins of TMA: widely used as paint resins for water-based and solvent-based coatings (Ullmann's).
● Alkyd coating resins: primarily water-based systems.
● Wall and floor coverings and paint formulations.
5.5 Dyes, Printing Inks & Other Intermediates
● Chemical intermediate for dyes and printing inks.
● Adhesives and polymer intermediates.
6. Packaging, Storage
Packaging (customizable):
● 25 kg multi-wall paper bags with PE liner, or fiber drums; small packs on request;
Storage:
● Store in a cool, dry, well-ventilated area; keep containers tightly closed;
● Protect from moisture and water; keep away from strong oxidizers;
● No open flames; prevent build-up of electrostatic charges (dust-explosion precautions per ICSC).
● Factory-direct supply: own production and sourcing capability, transparent pricing, no middleman markup.
● Stable quality: strict internal control, every batch tested (assay, acid value, melting point), COA with every shipment.
● Fast response: quotations and technical support (COA, SDS, application advice); small trial orders accepted.
TMA's largest use is making trimellitate plasticizers for poly(vinyl chloride) — high-temperature, low-volatility plasticizers for wire & cable insulation, automotive upholstery, gaskets and other heat-exposed flexible PVC. It is also an epoxy resin curing agent, a monomer for poly(amide-imide) and poly(ester-imide) heat-resistant insulation resins, a building block of water-based and solvent-based alkyd/polyester coating resins, and an intermediate for dyes and printing inks.
Trimellitate plasticizers made from TMA are high-molecular-weight triesters (three ester arms per molecule). Their high molecular weight and branching give them very low volatility, low migration and stable flexibility at elevated service temperatures — exactly the properties needed where ordinary general-purpose plasticizers (DOP/DINP type) would evaporate or migrate out. That is why trimellitate-plasticized PVC is the standard choice for wire & cable insulation, automotive interiors and other high-temperature applications.
Phthalic anhydride (PA, CAS 85-44-9) is the 1,2-benzenedicarboxylic anhydride (C₈H₄O₃) — the classic raw material of general-purpose DOP/DINP-type PVC plasticizers. Trimellitic anhydride (CAS 552-30-7, C₉H₄O₅) carries an additional carboxyl group on the ring, giving three reactive sites instead of two; its esters (trimellitates) are higher-molecular-weight, lower-volatility plasticizers for high-temperature PVC, and it forms specialty resins (polyamide-imides, heat-resistant coatings) that PA does not. They also differ in hazard profile: PA is not classified as a respiratory sensitizer, while TMA is (H334) and is an EU SVHC. Always specify the exact product and CAS when ordering.
