Glycolic acid (C2H4O3) is a 2-hydroxy monocarboxylic acid that is acetic acid where the methyl group has been hydroxylated. It has a role as a metabolite and a keratolytic drug.
| IUPAC Name | 2-Hydroxyacetic acid |
| Molecular Formula | C2H4O3 |
| CAS Number | 79-14-1 |
| Synonyms | Hydroxyacetic acid, Glycollic acid, Hydroacetic acid |
| InChI | InChI=1S/C2H4O3/c3-1-2(4)5/h1,3H,(H,4,5) |
Glycolic Acid Properties
Glycolic Acid Formula
The formula of glycollic acid is C2H4O3. It consists of two carbon atoms, four hydrogen atoms, and three oxygen atoms. This simple molecular formula represents the composition of glycollic acid.
Glycolic Acid Molar Mass
The molar mass of glycollic acid is calculated by adding the atomic masses of its constituent elements. With two carbon atoms (C = 12.01 g/mol), four hydrogen atoms (H = 1.01 g/mol), and three oxygen atoms (O = 16.00 g/mol), the molar mass of glycollic acid is approximately 76.05 g/mol.
Glycolic Acid Boiling Point
glycollic acid has a boiling point of approximately 290 °C (554 °F). This temperature represents the point at which glycollic acid undergoes a phase change from a liquid to a gas when heated under standard atmospheric conditions.
Glycolic Acid Melting Point
The melting point of glycollic acid is around 75 °C (167 °F). At this temperature, glycollic acid transitions from a solid to a liquid state. The melting point provides important information about the physical properties of glycollic acid.
Glycolic Acid Density g/mL
The density of glycollic acid is about 1.41 g/mL. This value indicates the mass of glycollic acid per unit volume. The density is an essential property that helps in understanding the behavior and characteristics of glycollic acid.
Glycolic Acid Molecular Weight
The molecular weight of glycollic acid is approximately 76.05 g/mol. It represents the sum of the atomic weights of all the atoms in one molecule of glycollic acid. The molecular weight is significant for various scientific calculations and analyses.
Glycolic Acid Structure
Glycollic acid has a structure consisting of a carboxylic acid group (–COOH) and a hydroxyl group (–OH) attached to the same carbon atom. This molecular structure gives glycollic acid its chemical and functional properties.
Glycolic Acid Solubility
Glycollic acid is highly soluble in water. It readily dissolves in water molecules, forming a homogeneous solution. This solubility property allows glycollic acid to be easily incorporated into various skincare and cosmetic products for effective application.
| Appearance | Colorless liquid |
| Specific Gravity | 1.26 – 1.29 g/mL |
| Color | Colorless |
| Odor | Odorless |
| Molar Mass | 76.05 g/mol |
| Density | 1.41 g/mL |
| Melting Point | 75 °C (167 °F) |
| Boiling Point | 290 °C (554 °F) |
| Flash Point | 111 °C (232 °F) |
| Water Solubility | Completely soluble |
| Solubility | Soluble in polar solvents |
| Vapour Pressure | 0.13 hPa at 20 °C |
| Vapour Density | 2.61 |
| pKa | 3.83 |
| pH | Approximately 2.4 |
Glycolic Acid Safety and Hazards
glycollic acid should be handled with care due to its potential hazards. It can cause skin and eye irritation, so protective gloves and goggles are recommended when working with it. Inhalation of vapors or mists should be avoided, as it may irritate the respiratory system. In case of contact with skin or eyes, immediate rinsing with water is crucial. glycollic acid is flammable, so it should be stored away from ignition sources. Furthermore, it is important to follow proper disposal procedures and store it in a well-ventilated area. Adhering to safety protocols is essential to minimize potential risks associated with glycollic acid.
| Hazard Symbols | Corrosive |
| Safety Description | Avoid contact with skin and eyes. Wear protective gloves and goggles. Handle in a well-ventilated area. Avoid inhalation. Store away from ignition sources. Follow proper disposal procedures. |
| UN IDs | UN 3265 |
| HS Code | 2918.14.00 |
| Hazard Class | 8 (Corrosive) |
| Packing Group | II |
| Toxicity | Moderately toxic by ingestion and inhalation. Can cause severe burns and irritation. |
Glycolic Acid Synthesis Methods
There are several methods to synthesize glycollic acid. One common method involves oxidizing glyoxal with nitric acid or hydrogen peroxide. Another method involves hydrolyzing mono-chloroacetic acid with water in the presence of a catalyst like sulfuric acid, yielding glycollic acid and hydrogen chloride as products.
Another synthesis method entails reacting formaldehyde with carbon monoxide and water, with the presence of a catalyst like a metal carbonyl or a palladium complex. This reaction produces glycollic acid and carbon dioxide as products.
A newer method for synthesizing glycollic acid involves directly oxidizing ethylene glycol with air, utilizing a catalyst such as platinum or palladium. This method, which is more environmentally friendly than others, yields high quantities of glycollic acid.
Bacterial fermentation is another method by which glycollic acid can produce. In this process, bacteria convert sugars into glycollic acid and other byproducts. However, this method is still under development and has not been widely adopted for industrial production.
The selection of a synthesis method for glycollic acid depends on factors such as cost, efficiency, and environmental impact.
Glycolic Acid Uses
glycollic acid finds extensive use in various industries and applications. Some key uses of glycollic acid include:
- Skincare products incorporate glycollic acid for its exfoliating properties, aiding in the removal of dead skin cells, unclogging pores, and enhancing skin texture and tone. Manufacturers use it in facial cleansers, toners, peels, and moisturizers.
- Glycollic acid actively stimulates collagen production, diminishing the visibility of fine lines and wrinkles. It contributes to a more youthful and revitalized appearance of the skin.
- Its efficacy in exfoliating and unclogging pores makes glycollic acid highly effective in acne treatment. It regulates oil production and minimizes the formation of acne lesions.
- Glycollic acid improves hyperpigmentation and lightens dark spots caused by sun damage or skin conditions like melasma. It promotes an even skin tone and fades discoloration.
- Chemical peels often contain glycollic acid as a prominent ingredient, as it aids in the removal of damaged outer skin layers. This reveals smoother and brighter skin underneath.
- Glycollic acid serves various roles in industrial applications, including textile dyeing and finishing, leather tanning, and oil drilling. It acts as a pH adjuster, chelating agent, and metal cleaner in these applications.
- Some household cleanings products, such as bathroom cleaners and tile/grout cleaners, utilize glycollic acid for the effective removal of mineral deposits and soap scum.
Questions:
Q: What does glycolic acid do?
A: Glycollic acid exfoliates the skin, promoting cell turnover, improving skin texture, reducing fine lines, and addressing hyperpigmentation.
Q: Is it okay to use glycolic acid everyday?
A: Daily use of glycollic acid may be suitable for some individuals, but it’s recommended to start with a lower frequency and gradually increase based on skin tolerance.
Q: Is glycolic acid an AHA?
A: Yes, glycollic acid is classified as an AHA (alpha hydroxy acid). It is derived from sugarcane and is known for its exfoliating properties.
Q: What does glycolic acid do to your face?
A: Glycollic acid exfoliates the skin, unclogs pores, improves skin tone and texture, and helps address various skin concerns like acne, hyperpigmentation, and signs of aging.
Q: What is glycolic acid?
A: Glycollic acid is a naturally occurring alpha hydroxy acid (AHA) derived from sugarcane. It is widely used in skincare for its exfoliating and rejuvenating properties.
Q: Can salicylic acid and glycolic acid be used together?
A: Salicylic acid and glycollic acid can be used together in skincare routines, as they target different concerns. However, it’s advisable to start with lower concentrations and observe skin tolerance.
Q: How many times a week to use glycolic acid?
A: The frequency of glycollic acid use depends on individual skin sensitivity, but starting with 1-2 times per week and gradually increasing can help minimize potential irritation and ensure optimal results.