glycolic acid CAS 79-14-1, glycolic acid, CAS 79-14-1
Glycolic acid CAS 79-14-1 Appearance: White crystalline solid or colorless crystal (pure product), industrial products are often 70% aqueous solution (pale yellow liquid).
79-14-1
C2H4O3
76.05
201-180-5
CAS | 79-14-1 |
Molecular formula | C2H4O3 |
Molecular weight | 76.05 |
EIENCS | 201-180-5 |
Form | Solution |
Melting point | 75-80 °C (lit.) |
boling point | 112 °C |
Density | 1.25 g/mL at 25 °C |
Solubility | H2O: 0.1 g/mL, clear |
PKA | 3.83(at 25℃) |
Color | White to off-white |
Storage temp | Store below +30°C. |
Physical properties
Appearance: White crystalline solid or colorless crystal (pure product), industrial products are often 70% aqueous solution (pale yellow liquid).
Melting point: 75-80°C (pure product) 10°C (70% aqueous solution).
Boiling point: 112°C (decomposition).
Density: 1.25-1.49 g/cm³ (due to morphological differences).
Solubility: Highly soluble in water (70% solution), ethanol, acetone, and ethyl acetate; Slightly soluble in ether.
pH value: 2 (50g/L aqueous solution).
Dual functional groups: Containing both carboxyl (-COOH) and hydroxyl (-OH) groups simultaneously, it has the reactivity of both acids and alcohols, and can form salts, esters, amides and polymers.
Acidity: pKa=3.83 (25℃), slightly stronger than acetic acid (due to the electron-withdrawing effect of hydroxyl groups).
Stability
Sensitive to heat and decomposes near the boiling point;
Incompatible with strong alkali, oxidants and reductants;
It is hygroscopic and should be stored in a sealed container away from light.
1. Personal care and cosmetics
Exfoliation and skin renewal: As an α -hydroxy acid (AHA), it has strong penetration and can dissolve keratinocytes, improving fine lines, acne scars and pigmentation.
Product types: Essence, anti-aging cream, exfoliating toner, etc. Common concentrations are 3%-10%.
Synergistic ingredients: It is often compounded with salicylic acid (BHA) to enhance the effect of oil control and acne removal.
2. Industrial applications
Chemical cleaning: A neutralizing agent used in metal pickling, electroplating additives and linen washing, taking advantage of its strong penetrating power.
Textiles and leather: Dyeing auxiliaries, tanning agents, enhancing the adhesion of dyes.
Polymer materials: Synthetic biodegradable polyglycolic acid (PGA), used in medical sutures and eco-friendly packaging.
3. Other fields
Medicine: Intermediate for the synthesis of antibiotics and vitamins.
Agriculture: Pesticide production (with an average annual demand growth rate of 4%).
Food industry: Food additives (must comply with safety standards).
Danger:
Corrosiveness: It is irritating to the skin, eyes and respiratory tract. Rinse immediately with clean water after contact.
GHS tag: pictographic ⚠️, signatory word "Dangerous" (H302 harmful to swallow, H314 causes burns).
Storage conditions:
Seal, avoid light, and keep in a cool and dry place (<30°C);
Stay away from oxidants and reductants.