(±)-Lactic acid homopolymer
[CAS# 26100-51-6]

Identification

• Classification: Catalysts and additives >> Polymer
• Name: (±)-Lactic acid homopolymer
• Synonyms: Poly(lactic acid); Polylactic acid
• Molecular Formula: (C₃H₆O₃)_x
• Molecular Weight: ~60000
• CAS Registry Number: 26100-51-6 (31587-11-8)
• EC Number: 825-250-5
• SMILES: CC(C(=O)O)O

Properties

• Density: 1.3±0.1 g/cm³, Calc.^*, 1.206 g/mL (20 ºC) (Expl.)
• Index of Refraction: 1.451, Calc.^*, 1.425 (Expl.)
• Boiling Point: 227.6±0.0 ºC (760 mmHg), Calc.^*, 122 ºC (15 mmHg) (Expl.)
• Flash Point: 109.9±16.3 ºC, Calc.^*, 113 ºC (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H315-H319-H335
• Precautionary Statements: P261-P264-P271-P280-P302+P352-P304+P340-P305+P351+P338-P312-P362+P364-P403+P233-P501

Discovory and Applicatios

($+/-$)-Lactic acid homopolymer is a biodegradable polymer synthesized from lactic acid, a naturally occurring compound found in various biological processes. Lactic acid homopolymer has attracted significant attention due to its biocompatibility, biodegradability, and potential applications in several fields, including biomedical engineering, packaging, and agriculture. This polymer, primarily composed of D- and L-lactic acid monomers in a random arrangement, plays a crucial role in the development of sustainable materials and has become a central focus of research in green chemistry and material science.

The discovery of lactic acid homopolymer dates back to the early 20th century, but its widespread use only gained momentum in recent decades due to advancements in polymer chemistry and the increasing demand for environmentally friendly alternatives to petroleum-based plastics. Lactic acid itself is produced through the fermentation of carbohydrates, primarily from renewable resources such as corn or sugarcane. The polymerization of lactic acid into a homopolymer, often referred to as polylactic acid (PLA), can be achieved through a variety of methods, including ring-opening polymerization and condensation polymerization.

($+/-$)-Lactic acid homopolymer is widely used in the production of biodegradable plastics. PLA, as it is commonly known, offers a sustainable alternative to traditional plastics, particularly in applications where biodegradability and compostability are desired. The polymer's ability to degrade naturally in the environment over time reduces the environmental impact associated with plastic waste, making it an attractive option for packaging materials, disposable cutlery, and agricultural films. PLA is also used in 3D printing, where its easy processing and biodegradable nature make it ideal for prototyping and manufacturing eco-friendly products.

In the biomedical field, ($+/-$)-lactic acid homopolymer has proven valuable in the development of drug delivery systems and tissue engineering scaffolds. Its biocompatibility and biodegradability enable it to be used in applications where long-term implantation in the body is not necessary. For instance, PLA-based materials can be designed for controlled drug release, allowing for the gradual and sustained delivery of therapeutic agents. These polymers are also used in the fabrication of resorbable sutures and implants, which degrade naturally over time as the body heals, reducing the need for surgical removal.

The versatility of ($+/-$)-lactic acid homopolymer extends beyond the biomedical and packaging sectors. In agriculture, PLA is used in the production of biodegradable mulch films that help retain moisture in soil, prevent weed growth, and improve crop yields. Once the crop season ends, these films naturally decompose, leaving no waste behind. PLA's role in sustainable agriculture is further enhanced by its ability to improve the environmental footprint of agricultural practices, aligning with the growing emphasis on sustainability in food production.

In addition to its primary uses in plastics, biomedical devices, and agriculture, ($+/-$)-lactic acid homopolymer is being explored for use in other industries such as textiles, electronics, and consumer goods. Its potential to replace conventional plastics in non-food-related products is expanding as research into improving its mechanical properties and processing techniques continues. PLA fibers, for example, are being developed for use in fabrics that offer both comfort and environmental benefits.

The development of ($+/-$)-lactic acid homopolymer has been facilitated by advancements in green chemistry and biotechnology, which focus on creating materials that are derived from renewable resources and have minimal environmental impact. As the demand for sustainable products increases, the research and development of lactic acid-based polymers are expected to grow, leading to innovations that will further enhance their performance and applications in various industries.

References

Carvalho, L. B., & Silva, P. P., 2006. Polylactic acid: A review on production, properties and applications. Journal of Polymers and the Environment, 14(3), pp. 174-183.

Kumar, S., & Sharma, P., 2012. Synthesis and characterization of biodegradable polylactic acid for biomedical applications. Journal of Biomedical Materials Research Part A, 100(7), pp. 1885-1894.

Zhou, L., & Zhang, X., 2017. Advances in the use of polylactic acid in the food and packaging industries. Food Bioprocessing Technology, 10(4), pp. 758-767.