Industrial grade, Fragrance grade 99% Benzyl benzoate CAS 120-51-4

What is benzyl benzoate? How does it work? What are its industrial applications?

1. What is Benzyl benzoate? How does it work?

Benzyl benzoate, also known as benzyl benzoate (or benzoic acid benzyl ester), is an ester formed from benzyl alcohol and benzoic acid. It is one of the most widely used benzoic acid ester plasticizers, solvents, and fragrance fixatives in industry. Its molecular formula is:

C14H12O2 (C6H5COOCH2C6H5, molecular weight approximately 212.25; CAS No.: 120-51-4; EC No.: 204-402-9)

It is a colorless to slightly yellow oily liquid at room temperature (it can solidify into white solid flakes at low temperatures), with a faint balsamic odor; density 1.118 g/cm³ (20℃), melting point 17-21℃, boiling point 323-324℃, flash point 148℃, autoignition point 480℃, vapor density 7.31, almost insoluble in water (0.0153 g/L, 20℃), soluble in most organic solvents such as ethanol, ether, and chloroform; it has low vapor pressure and extremely low volatility. Industrially, it is prepared by the reaction of sodium benzoate with benzyl chloride, or as a byproduct of the oxidation of toluene to benzoic acid, and by the Tishchenko reaction of benzaldehyde; it is naturally found in flowers such as tuberose and hyacinth, as well as in Peruvian balsam and toluene balsam.

Structurally, benzyl benzoate consists of a benzene ring (benzoic acid end), an ester group (-COO-), and another benzylbenzene ring (benzyl alcohol end). The two aromatic rings give it a strong affinity for aromatic substances (like dissolves like), and the ester group provides a polar end, enabling it to be compatible with polar polymers. The entire molecule is rigid but of moderate size, and can insert between polymer chains to play a plasticizing and swelling role. This is the structural root of its multiple roles as a plasticizer, solvent, carrier, and fixative.

Chemically, benzyl benzoate is a stable aromatic ester: it is not easily hydrolyzed, has good heat resistance (high boiling point, low vapor pressure), and is almost non-volatile. In vivo, it can be rapidly hydrolyzed into benzoic acid and benzyl alcohol (both are low in toxicity and can be metabolized and excreted), therefore its acute toxicity is low. It is somewhat irritating to the skin and toxic to aquatic organisms (GHS hazard: H3O2 is harmful if ingested, H411 is toxic to aquatic organisms). It should be stored in a sealed container, protected from light, and away from strong oxidizers.

From the perspective of mechanism of action, benzyl benzoate exerts its effects through the unique properties of "plasticizing and swelling + strong solubility + insecticidal toxicology + fragrance fixation and sustained release + pharmaceutical carrier". The mechanisms of action in different industrial applications are as follows:

1.Plasticizing and swelling mechanism (intercalation between polymer chains)

Benzyl benzoate has a moderate molecular size and good compatibility with a variety of polymers. It can insert between polymer molecular chains, weaken the inter-chain interaction forces, increase the degree of freedom of chain segment movement, and lower the glass transition temperature (Tg), thereby making rigid polymers softer and tougher. For polyester fibers, this swelling effect can expand the fiber molecular chains and allow dye molecules to penetrate, which is a common mechanism of plasticization and carrier dyeing.

2.Strong dissolution mechanism (like dissolves like)

The two benzene rings give it a strong affinity for aromatics, resins and a variety of organic solutes, while the ester group gives it the ability to dissolve polar components. Combined with its high boiling point and low volatility, it is an excellent solvent and carrier liquid for dissolving cellulose derivatives, resins, fragrances, pesticide technicals and other materials.

3.Fixative sustained-release mechanism (low volatility, slow release)

Benzyl benzoate has an extremely low vapor pressure and is almost non-volatile. In fragrances, it can "lock in" volatile top notes and slow down their escape rate, allowing the overall aroma to be released slowly and stably. At the same time, it has a mild, sweet balsamic aroma that harmonizes with floral and fruity scents, making it a classic fixative in the fragrance industry.

In summary, benzyl benzoate is a versatile aromatic ester fine chemical: as a plasticizer, it inserts between polymer chains to soften plastics and swell fibers to achieve carrier dyeing; as a solvent, it dissolves cellulose derivatives and various materials; as an insect repellent active ingredient, it kills mites and lice; and as a fixative, it prolongs the fragrance's longevity. It is one of the most widely used benzoate products in industrial applications.

What are all the uses of industrial-grade Benzyl benzoate?

Benzyl benzoate has industrial applications spanning multiple industrial sectors, including plastics, textiles, fine chemicals, agrochemicals, and daily chemicals.

1.Polymer plasticizers and polyester fiber carrier dyeing agents (core applications in the plastics and textile industries).

Application Areas: Plastics processing and textile printing and dyeing.

Corresponding Products: Plasticizers for PVC artificial leather/films/hose/wires and cables, nitrocellulose/cellulose acetate plasticizers, rubber plasticizers and softeners, polyester disperse dye carriers, and acrylic/cellulose acetate dyeing and finishing auxiliaries.

Why it works for this purpose: Benzyl benzoate molecules can insert into the polymer chains, weakening interchain forces and lowering the glass transition temperature, making rigid plastics and resins softer and tougher, improving processability and flexibility. It is a classic auxiliary plasticizer for PVC and cellulose esters. For polyester fibers, the same swelling effect can expand the fiber molecular chains, allowing disperse dyes to penetrate and dye, achieving atmospheric pressure boiling dyeing. It is a traditional and effective auxiliary agent for polyester carrier dyeing—plastic plasticizing and carrier dyeing are essentially based on the same "plasticizing swelling" principle, hence they are combined into one.

2.Industrial solvents and carrier liquids (core application in fine chemicals).

Application fields: Pharmaceutical and fine chemicals industries.

Related products: Cellulose derivative solvents, inkjet ink solvents, paint/ink/adhesive solvents, fragrance solvents, organic chemical synthesis reaction media.

Why this application is appropriate: Benzyl benzoate has a bibenzene ring structure which has high solubility for aromatic resins and a variety of organic solutes. The ester group is also a solvent for polar components. It is suitable as a solvent and carrier liquid for inks, paints, adhesives, fragrances and pesticide formulations requiring low volatility and high solubility, combined with high boiling point (323℃) and near-non-volatile nature and low toxicity. It is also a low toxicity alternative to some very volatile aromatic solvents.

3. Fragrance fixatives and solvents for flavorings and fragrances (daily chemical industry)

Application areas: Fragrance and flavor industry and daily chemical industry.

Corresponding products: Perfume/cologne fixative, soap/detergent fragrance, cosmetic fragrance formulation, floral fragrance component.

Why it works for this purpose: Benzyl benzoate has an extremely low vapor pressure and is almost non-volatile, which can slow down the escape of volatile top notes in fragrances and prolong the lasting fragrance. At the same time, its mild, sweet balsamic aroma harmonizes with floral, fruity, and herbal scents, and it can also dissolve various fragrance crystals (as a fragrance solvent). It is one of the most widely used fixatives in daily chemical fragrance formulations.

In summary, benzyl benzoate (CAS 120-51-4) is the fine benzoate ester most frequently used. 5 mechanisms of action plasticizing and swelling, strong solubility, insect repellency and toxicology, and fragrance fixation and sustained release. Mature applications plastics (PVC/cellulose ester plasticizers), textiles (polyester carrier dyeing), fine chemicals (inks/coatings/adhesives/fragrances/pesticide solvents), agricultural and hygiene chemicals (mite and insect repellents), daily chemicals (fragrance fixation) This classic product is a benzoate ester which is of low volatility, low toxicity and good compatibility with aromatic systems, and has the functions of a plasticizer, a solubilizer, an insect repellent and a fragrance fixative.