Description

2,2',3,3'-Tetrahydro-5,5'-Diisononyl-3,3,3',3'-Tetramethyl-1,1'-Spirobi[1H-Indene]-6,6'-Diol is a high-performance hindered phenolic antioxidant, valued for its exceptional ability to inhibit oxidative degradation in polymers and other sensitive materials. Its complex, high-molecular-weight structure provides superior thermal stability and low volatility, making it a critical additive for extending product lifespan under demanding conditions. This compound is essential for formulators and manufacturers in the plastics, rubber, and specialty chemical industries seeking reliable long-term stabilization solutions.

Application

• Primary antioxidant in polyolefins (PP, HDPE, LDPE) for processing and long-term heat stabilization.
• Stabilizer for engineering plastics and styrenic polymers to prevent yellowing and embrittlement.
• Additive in adhesives, sealants, and elastomers to enhance durability and resistance to thermal-oxidative aging.
• Key component in lubricant and grease formulations to inhibit oil oxidation and sludge formation.
• Stabilizing agent for synthetic fibers during high-temperature processing and end-use.
• Used in food-contact polymer applications where regulatory-compliant stabilization is required.
• Synergistic component in antioxidant blends with phosphites or thioesters for comprehensive stabilization packages.

Basic Information

Product Name	2,2',3,3'-Tetrahydro-5,5'-Diisononyl-3,3,3',3'-Tetramethyl-1,1'-Spirobi[1H-Indene]-6,6'-Diol
CAS No.	73529-70-1
Molecular Formula	C41H64O2
Molecular Weight	589.0 g/mol
Synonyms	Bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite (common mis-association, but a different compound); 1,1'-Spirobi[1H-indene]-6,6'-diol, 2,2',3,3'-tetrahydro-5,5'-diisononyl-3,3,3',3'-tetramethyl-; High molecular weight hindered phenol antioxidant; AO-80 (potential trade designation); Pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) analog (structural analog); Bis-phenol antioxidant; Diisononyl-substituted spirobiindanediol.
EINECS	Contact for details

Quality Control

Our production of 2,2',3,3'-Tetrahydro-5,5'-Diisononyl-3,3,3',3'-Tetramethyl-1,1'-Spirobi[1H-Indene]-6,6'-Diol adheres to a strict quality management system to ensure batch-to-batch consistency and high purity. Each lot is analyzed against rigorous in-house specifications using advanced techniques like HPLC, GC, and NMR. A comprehensive Certificate of Analysis (COA) detailing purity, identity, and key physical parameters is provided with every shipment to support your quality assurance protocols.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed after initial opening to prevent absorption of atmospheric moisture, which can affect product performance.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to reference spectrum
Assay (HPLC)	≥ 98.0%
Melting Point	110 - 125 °C
Loss on Drying	≤ 0.5%
Heavy Metals (as Pb)	≤ 10 ppm
Residue on Ignition	≤ 0.1%

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.