Chemical properties of OA-14

While "OA-14" is not a standard chemical name you would find in a major registry like PubChem, it is a recognized tradename and abbreviation within specific industries, particularly oilfield chemicals and corrosion inhibition.

Based on its common industrial use, OA-14 is understood to be Oleyl Amidopropyl Dimethylamine, a fatty amine derivative. It acts as a precursor to a cationic surfactant and is highly valued for its corrosion inhibiting properties.

Here are the detailed chemical properties of OA-14:

1. Chemical Identity

Common Name: OA-14

Systematic / IUPAC Name: N-(3-(Dimethylamino)propyl)oleamide or Oleyl Amidopropyl Dimethylamine

CAS Number: 109-28-4 (This CAS is for the closely related "Oleyl Propylenediamine", and OA-14 is often categorized under this or similar CAS mixtures).

Chemical Formula: C₂₃H₄₇N₃O (for the oleyl variant)

Molecular Weight: ~ 381.64 g/mol

2. Structural Properties

Structure: CH₃(CH₂)₇CH=CH(CH₂)₇C(O)NH(CH₂)₃N(CH₃)₂

Key Functional Groups:

Amide Group (-C(O)NH-): Provides stability and links the fatty chain to the amine group.

Tertiary Amine Group (-N(CH₃)₂): This is the active site. It can be protonated to form a water-soluble cationic ammonium salt, which allows it to adsorb h3ly onto negatively charged metal surfaces.

Long Hydrophobic Alkyl Chain (C18, with a double bond): The oleyl chain provides a hydrophobic barrier that shields the metal from water and corrosive ions.

3. Physical Properties (Typical)

Appearance: Clear viscous liquid to a pale yellow semi-solid, depending on temperature.

Odor: Characteristic mild amine-like odor.

Solubility:

Soluble in: Most organic solvents (e.g., ethanol, isopropanol, toluene, xylene, kerosene, diesel).

Insoluble in: Water (in its free amine form). It becomes water-dispersible when neutralized with an acid (e.g., acetic acid) to form its salt.

Density: ~ 0.89 - 0.91 g/cm³

Melting Point: Not a sharp point, but typically softens or becomes liquid above 15-20°C.

4. Chemical Properties and Reactivity

Acid-Base Behavior: This is its most important chemical property. OA-14 is a weak base. It readily reacts with acids to form stable, water-soluble salts.

OA-14 (amine) + HCl → [OA-14H]⁺ Cl⁻ (ammonium salt)

This reaction is why it's often supplied as an acid salt or neutralized on-site for application in water-based systems.

Corrosion Inhibition Mechanism: The protonated (cationic) form adsorbs electrostatically onto the negatively charged cathodic sites (e.g., Fe²⁺ sites) of a metal surface. The long hydrophobic tail then orients itself outward, forming a protective film that blocks water, oxygen, and corrosive ions (like Cl⁻) from reaching the metal.

Stability: Stable under normal storage conditions. It is hygroscopic (can absorb moisture from the air).

Compatibility: Compatible with most cationic and nonionic surfactants. Incompatible with h3 oxidizing agents and anhydrides. It can form precipitates with anionic surfactants.

5. Functional Properties & Uses

Primary Function: Excellent Corrosion Inhibitor.

Application: Extensively used in acidizing treatments (HCl, HF acids) in the oil and gas industry to protect downhole tubulars and surface equipment from acid corrosion. Also used in industrial cleaning acids and water-cooling systems.

Synergist: Often formulated with other inhibitors (e.g., alkynols like propargyl alcohol), surfactants, and solvents to enhance performance and provide multifunctional properties (e.g., anti-sludging, demulsification).

Secondary Function: Surfactant & Emulsifier.

Its structure allows it to reduce surface tension and help stabilize or break emulsions, depending on the formulation.

6. Handling and Safety (GHS Classification - Typical)

Signal Word: Warning

Hazard Statements:

H315: Causes skin irritation.

H319: Causes serious eye irritation.

H335: May cause respiratory irritation.

Precautionary Statements: Use personal protective equipment (gloves, eye/face protection). Ensure adequate ventilation.

Storage: Store in a cool, dry, well-ventilated place in a tightly closed container.

Summary Table of Key Properties

Property Category Description of OA-14

Chemical Class Fatty amine derivative (Oleyl Amidopropyl Dimethylamine)

Molecular Formula C₂₃H₄₇N₃O

Appearance Viscous liquid to semi-solid (pale yellow)

Key Functional Groups Tertiary Amine, Amide, Long Alkyl Chain

Solubility Oil-soluble (free amine); Water-dispersible (acid salt)

Primary Mechanism Film-forming adsorption corrosion inhibitor

Main Application Corrosion inhibitor in oilfield acidizing and industrial acids

Important Note: The exact properties (like viscosity, color, and even exact composition) can vary between manufacturers. Always consult the specific Safety Data Sheet (SDS) and technical data sheet provided by your chemical supplier for the most accurate and precise information.