The Glypure® 99% crystalline grade of Glycolic Acid is chemically stable to 50°C (122°F). Above this temperature, polymerization begins to occur.
Both lactic acid and glycolic acid were extremely stable and not subject to thermal decomposition.
Anti-aging products with ingredients like retinol, glycolic acid and vitamin C can break down quickly and typically last nine months to one year, depending on how they're dispensed. Opt for vacuum-sealed products in air-tight pump bottles for a longer lasting product.
Glycolic acid is stable and will not degrade when stored in an unopened container in ambient temps up to 140 F.
Understanding citric acid stability at high temperatures**Thermal Stability**Citric Acid (C6H807) is generally thermally stable up to around 428 Deg. F (220 Deg C) before significant decomposition occurs. At 365 Deg F.
Explanation: When citric acid is heated at 170 degrees Celsius, it undergoes a chemical reaction called thermal decomposition. This reaction breaks down the citric acid into water, carbon dioxide, and a compound called acetic acid.
Thermal stability temperature of ascorbic acid is increased to 188 °C. After 60 days of storage at room temperature, the retention of ascorbic acid is around 90%. The retention of ascorbic acid is around 81.3% after 90 days of storage at 21 °C.
Chemical and Physical Stability
Glycolic Acid 70% technical solution and DuPont™ Glypure® 70% solution are chemically stable when stored at normal temperatures. The solution products are physically stable if they are stored at temperatures above 10°C (50°F). At colder temperatures, Glycolic Acid crystals can form.
Some active ingredients like Retinol, Glycolic Acid and Lactic Acid are best left at room temperature as drastic changes can impact their integrity. A good rule of thumb is to chill formulas that aim to hydrate and soothe, whereas exfoliants and anti-agers are best stored at room temperature.
The Ordinary Glycolic Acid costs just £11.50 for a big ol' bottle that'll probably last you 6 months or so if you're using it 2 or 3 times a week. Obviously, if you're slathering it over your body to benefit from its skin-smoothing effects, it might not last so long.
Neutralisation is required to terminate the action of gly- colic acid peels and can be achieved using water, sodium bicarbonate, sodium hydroxide or ammonium salt solu- tions.
Because Glycolic Acid exfoliates the top layer of the skin, we would recommend avoiding any other products that also promote skin cell turnover. This would include ingredients such as Retinoids and Copper Peptides. Combining multiple resurfacing products may increase the chances of developing skin sensitivities.
Glycolic Acid, especially in high-strength solutions, can irritate the skin. If you have sensitive skin, a low-strength glycolic acid treatment can be added to your skincare routine. However, you should introduce them gradually, utilizing them just once or twice a week.
As such, when using skincare products such as glycolic acid, it is advisable to maintain a suitable sun-protection routine, such as applying a broad-spectrum sunscreen. A person will also need to avoid tanning beds.
"In fact, water from sweat will neutralize glycolic acid, reducing any benefits of the acid application," she says. In other words, any benefits of that nature are based on anecdotal evidence. One thing glycolic acid may help improve is underarm pigmentation.
Acids. Products containing acids like salicylic acid or glycolic acid should not be used past their shelf life, which is often around one year. Products with acids often become more potent (and more irritating) over time.
Exfoliating acids, like salicylic acid (BHA) and glycolic acid (an AHA), work best when kept in room temperature conditions. In fact, when in certain solvents (methanol, ethyl acetate, etc.) at cool temperatures, salicylic acid can crystalize (9).
What NOT to mix with Glycolic Acid. Retinol, other AHAs/BHAs, Vitamin C: Using these ingredients alongside Glycolic Acid in the same routine could irritate the skin. However, alternating them between your morning and evening skincare routine means that you can enjoy the benefits without the risk of damaging your skin.
As an AHA, glycolic acid chemically exfoliates the skin and boosts collagen production. If you want to try an OTC glycolic cleanser, toner, serum, or peel, start slow and let your skin adjust. Glycolic acid can cause irritation and redness if you have sensitive skin or overuse the product.
Temperature stability is the ability of the material to retain its original property when exposed to heat. It is generally expressed by the ultimate temperature, exceeding the point of which the material will lose its heat-insulating function.
When vitamin A palmitate was treated with temperature of 80 °C for 15 min, the degradation rate was found to be about 60%, and when the temperature was increased to 100 °C and the time was extended to 30 min, vitamin A was completely degraded.
4.7 High thermal stability
Thermal stability can be described as the ability of a material to resist breaking down under heat stress. The maximum usage temperature is the highest temperature to which a material may be heated without breaking down or degrading.