Lactic acid is a colourless, hygroscopic liquid which is white in its solid state. It is an organic compound, and can be classified as an alpha-hydroxy acid (AHA) because of its structure which contains a hydroxyl group adjacent to the carboxyl group. It is present naturally, and can be produced synthetically. It is also known as milk acid as it is primarily found naturally in milk products. It is also formed by exertion of glycogen by muscle cells in the human body due to anaerobic respiration. Industrially, it is produced either by the fermentative method which involes bacterical fermentation of nearly any carbohydrate, or by the chemical method where lactic acid is synthesised from the acetaldehyde extracted from coal or crude oil. To find out more about lactic acid, visit our website.
Among its other potential applications in the food, pharmaceuticals, and cosmetics industries, an important potential use of lactic acid is as the key building block in the polymer PolyLactic Acid (PLA). PLA can be used as a biodegradable plastic (or “bioplastic”) which is bio-based, and hence is derived from renewable resources such as corn starch or sugarcane, as opposed to the conventional plastic which is petroleum based. Its characteristics are similar to the commonly used plastics such as polypropylene, polyethylene, or polystyrene, and can be produced from the already existing plastic manufacturing equipment. Hence, this bioplastic is relatively cost-efficient to produce. Its economical and environmental benefits make it a very useful plastic with the potential to overtake the non-renewable and non-biodegradable plastics.
PLA plastics are applicable in a wide variety of industries. Common uses of PLA plastic include plastic films, bottles, printing filaments, and biodegradable medical devices such as screws, pins, rods, and plates. However, its low glass transition temperature makes PLA unsuitable for high temperature applications such as bottles to hold hot liquids.