Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate
[CAS# 67845-93-6]

Identification

• Classification: Organic raw materials >> Carboxylic compounds and derivatives >> Carboxylic esters and their derivatives
• Name: Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate
• Synonyms: 3,5-Bis[1,1-dimethylethyl]-4-hydroxybenzoic acid hexadecyl ester
• Molecular Formula: C₃₁H₅₄O₃
• Molecular Weight: 474.76
• CAS Registry Number: 67845-93-6
• EC Number: 267-342-2
• SMILES: CCCCCCCCCCCCCCCCOC(=O)C1=CC(=C(C(=C1)C(C)(C)C)O)C(C)(C)C

Properties

• Density: 0.9±0.1 g/cm³, Calc.^*
• Index of Refraction: 1.489, Calc.^*
• Boiling Point: 539.2±50.0 °C (760 mmHg), Calc.^*
• Flash Point: 191.3±22.9 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS09 Warning
• Risk Statements: H411
• Safety Statements: P273-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335

Discovery and Applications

Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate is a chemical compound primarily used as a UV stabilizer and antioxidant in a variety of industrial applications. Its discovery and subsequent development are linked to the need for materials that offer enhanced protection against UV degradation, especially in polymers and plastics. As a derivative of hydroxybenzoic acid, this compound incorporates a hexadecyl group for increased solubility and stability, making it highly effective in protecting materials from the harmful effects of ultraviolet (UV) light.

The structure of Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate consists of a hydroxybenzoate backbone, with bulky tert-butyl groups at the 3 and 5 positions of the aromatic ring. These substitutions enhance the compound’s ability to absorb UV radiation, while the long hexadecyl chain provides improved solubility in non-polar solvents and compatibility with a wide range of polymer matrices. The combination of these features makes the compound an ideal candidate for incorporation into polymers and coatings that require long-term stability under sunlight exposure.

The primary application of Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate is as a UV absorber in polymer formulations. When added to materials such as polyolefins, PVC, and other synthetic polymers, this compound effectively reduces the degradation caused by UV light exposure. It works by absorbing UV radiation and converting it into harmless heat, thereby preventing the breakdown of the polymer chains. This action helps preserve the mechanical properties, color, and appearance of plastic products, extending their useful life in outdoor applications such as automotive parts, outdoor furniture, and packaging materials.

Additionally, Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate is used in coatings and paints to enhance the longevity of the surface treatment. In these applications, the compound’s UV-absorbing properties help prevent fading and discoloration of the painted surfaces, which is especially beneficial in architectural coatings and automotive finishes.

Another significant application of this compound is in the field of cosmetics and personal care products, where it functions as a sunscreen agent. It is used to protect skin and hair from the harmful effects of UV radiation, offering additional protection against photoaging and skin damage. Its effectiveness in cosmetics is largely due to its ability to stabilize formulations and prevent the breakdown of active ingredients under UV exposure.

Moreover, Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate has also found applications in the field of agriculture, where it is incorporated into agricultural plastics to reduce UV degradation, thus extending the lifespan of materials such as greenhouse films and irrigation pipes.

In conclusion, Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate is a highly effective UV stabilizer and antioxidant with a wide range of applications in the polymer, coatings, cosmetics, and agricultural industries. Its discovery marked a significant advancement in material science, providing a versatile solution for improving the durability of products exposed to sunlight.

References

2021. A lipid coating on cotton fibers with enhanced adsorption capability for fabric functionalization. Cellulose, 28(7).
DOI: 10.1007/s10570-021-03893-9

2017. Screening of additives and other chemicals in polyurethanes by direct analysis in real time mass spectrometry (DART-MS). Analytical and Bioanalytical Chemistry, 409(23).
DOI: 10.1007/s00216-017-0553-x