Acrylic Acid is an organic compound with the chemical formula CH₂=CHCOOH. This colorless liquid has a sharp, characteristic odor and is highly reactive due to the presence of both a carboxyl group and a carbon-carbon double bond in its structure.

Structure

The structure of acrylic acid includes a vinyl group (CH₂=CH) and a carboxyl group (–COOH). The carbon-carbon double bond (vinyl bond) is responsible for its high reactivity in polymerization reactions, while the carboxyl group makes it a weak acid and enables esterification reactions.

Properties of Acrylic Acid

Physical State: Colorless, transparent liquid
Odor: Sharp, pungent smell
Solubility: Completely soluble in water, alcohols, ethers, and chloroform
Reactivity: Highly reactive, particularly prone to polymerization. It is commonly stabilized with a small amount of a polymerization inhibitor (such as monoethyl ether of hydroquinone or MEHQ) to prevent spontaneous polymerization during storage
Boiling Point: 139°C
Melting Point: 13°C
Acidity: Weak acid

Applications of Acrylic Acid

Acrylic acid is used in a wide range of industries due to its unique properties:

Polymer and Resin Production: Its primary use is in producing acrylic polymers (polyacrylates), which are used in paints, coatings, adhesives, water-repellent materials, and inks.
Coatings and Paints Industry: As a main monomer in producing emulsions and acrylic resins for architectural paints, automotive coatings, and industrial finishes.
Superabsorbent Polymers (SAPs): Polymers derived from acrylic acid, particularly sodium polyacrylate, are highly water-absorbent and used in baby diapers, feminine hygiene products, and agriculture (as moisture retainers for soil).
Textile Industry: In the production of acrylic fibers and fabrics with excellent resistance to sunlight and weathering.
Petroleum Additives: To enhance the properties of oils and lubricants.
Water Treatment Chemicals: Used as a scale inhibitor and dispersant.
Pharmaceuticals: In the synthesis of certain pharmaceutical compounds.

Advantages of Acrylic Acid

Versatile Applications: Due to its high reactivity and polymerization ability, it is used to manufacture a wide variety of products.
High Performance: Its polymers exhibit excellent mechanical, optical, and chemical properties.
High Resistance: Final products made from acrylic acid (e.g., paints and coatings) show good resistance to weather, UV radiation, and chemicals.
Excellent Adhesion: Widely used in the production of strong and durable adhesives.

Disadvantages of Acrylic Acid

Toxicity and Corrosiveness: Acrylic acid is a corrosive liquid that can cause severe irritation to the skin, eyes, and respiratory system. Prolonged or repeated exposure may result in serious harm.
Pungent Odor: Its strong smell can be unpleasant and irritating at high concentrations.
Flammability: It is flammable, and its vapors can form explosive mixtures with air.
Spontaneous Polymerization: In the absence of an inhibitor, it has a strong tendency to polymerize spontaneously, which can be hazardous and damage storage containers.
Environmental Impact: If released into the environment, it can be toxic to aquatic life.