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Poly l Lactic Acid CAS 50-21-5

Molecular Formula: C3H6O3

Formula Weight: 90.08

ZSpharmac: Poly l Lactic Acid Supplement

Product Name: Poly l Lactic Acid
CAS No: 50-21-5
Purity: 99%

Basic Info

Product Name:Poly l Lactic Acid
Other Names:Lactic acid
Place of Origin:Shandong, China
Brand Name:ZSpharmac
Type:Food Additives
Appearance:Colorless to Yellow Syrup
EINECS No.:200-018-0
Provide:Poly l Lactic Acid MSDS;
Poly l Lactic Acid COA

What is Poly l Lactic Acid?

Poly l Lactic Acid is a vital natural acid, the 2nd organic acid 2nd just to citric acid in manufacturing and consumption. There is an uneven carbon atom in the molecular structure, developing two optical isomers d-body, l-body and racemate dl-body, an overall of 3 an optical isomer. In 1780, Scheele got this product in yogurt, hence the name lactic acid. There are dextro- as well as racemates in human and also animal meat cells, while levo-isomers are normal metabolites in animals. It is also normally found in poppy, apple, tomato juice and also other fruits. Commercially offered products are racemates despite whether they are acquired by fermentation or synthesis. Because of the existence of hydroxyl as well as carboxyl groups in the particle, this product has the features of these two functional teams, as well as can create carboxylate with acid anhydride, type lactate with alcohol, and kind salt with salt, calcium, ferrous ions and various other ions; Hydroxyl and carboxyl groups, consequently, can go through self-esterification to produce direct polyesters and also even cyclic substances, namely cyclic dimer lactide [2] Under sluggish oxidation, this product can create pyruvic acid, and when heated to above 250 ℃, it will break down and decay, produce acetaldehyde, as well as release co2 and water. Responds with ammonia or amines to produce Poly l Lactic Acid amides. In addition to the self-esterification of the hydroxyl as well as carboxyl teams of this product, the hydroxyl and carboxyl teams can likewise participate in the response at the same time, such as responding with aldehydes or ketones to create cyclic acetals. Salt lactate is used in medication to prevent and also deal with acidosis.

Poly l Lactic Acid Properties:

Melting point 18°C
alpha -0.05 º (c= neat 25 ºC)
Boiling point 122 °C/15 mmHg (lit.)
density 1.209 g/mL at 25 °C (lit.)
vapor density 0.62 (vs air)
vapor pressure 19 mm of Hg (@ 20°C)
refractive index n20/D 1.4262
Fp >230 °F
storage temp. 2-8°C
solubility Miscible with water and with ethanol (96 per cent).
pka3.08(at 100℃)
form syrup
color Colorless to yellow
Specific Gravity1.209
PH3.51(1 mM solution);2.96(10 mM solution);2.44(100 mM solution);
Water Solubility SOLUBLE


Poly l Lactic Acid Uses

  1. Poly l Lactic Acid is a commonly used natural acid, which can be made use of in developing, medicine, natural leather, cigarette, chemical market, food, printing and dyeing, and so on. The usage distribution of Poly l Lactic Acid in Japan is roughly: about 20% for developing, concerning 50% for food, regarding 10% for Poly l Lactic Acid derivatives, and also regarding 20% for commercial use such as natural leather. The distribution of uses in my country is approximately the very same. 1. Brewing sector About 80% Poly l Lactic Acid is made use of in the developing market. The addition of lactic acid can avoid the recreation of miscellaneous microorganisms, promote the development of yeast, prevent the turbidity of the white wine and also strengthen the taste of the a glass of wine, as well as can also boost the return of the red wine. 2. Food industry The food industry typically uses Poly l Lactic Acid with a content of 50%. Mostly utilized in lactic acid beverages, rejuvenating beverages, cakes, pickles and sour agents. Poly l Lactic Acid can make food a little acidic without masking the natural flavor as well as aroma of fruits and also steamed vegetables. As a result, it is extensively utilized in canned foods such as tomatoes, olives, pickled cucumbers, and sour cabbage, and also yogurt beverages made with lactic acid bacteria are also very popular. 3. Lactic acid in pharmaceutical sector can be straight created right into medication or made use of as lactate. Oral administration can be utilized for digestive disinfection. It can also liquify protein as well as keratin, as well as is particularly conscious the deterioration of infected cells, so it can be made use of to treat throat consumption, diphtheria, lupus and also other illness. In addition, it is also made use of for sanitation of the sword: containing cough representative, covering representative, bladder injection, vaginal cleanser. The hydrophilic qualities of lactic acid are integrated with insoluble medicines to boost the absorption of medications and prevent negative effects. Poly l Lactic Acid is likewise a resources for making erythromycin sugar coating, so it is extensively made use of in the pharmaceutical industry. 4. The web content of Poly l Lactic Acid used as a whole leather in the natural leather industry is 40%. It does not have high requirements on the top quality of Poly l Lactic Acid, and can be made use of in dark or fragrant ones. The tanning sector generally utilizes it to get rid of lime from tanned leather, additionally called deliming. The high quality of leather after deliming with Poly l Lactic Acid is much better than various other acids. The deliming high quality is excellent, and the state-of-the-art natural leather should be treated with Poly l Lactic Acid. In the manufacturing of cigarettes, Poly l Lactic Acid can be used to eliminate impurities in tobacco as well as get rid of bitter as well as hot preference. Consequently, the grade of low-grade cigarette can be enhanced by Poly l Lactic Acid treatment. Lactic acid is made use of as a pH control agent in the production of celluloid coverings; in the wool fabric industry for pre-chrome mordant dyeing of dyes to minimize the chromate material of woollen as well as stop fiber oxidation; in the post-processing of silk as well as rayon, as a pH insurance adjuster Agent, used for brightening therapy to boost the color of thread. Pure lactic acid is unsavory, and the item has a somewhat similar fragrance to cool down milk. When the concentration is appropriate, it has a pleasant sour taste. When lactic acid is utilized as a resources, it is mostly used as a component of milk flavors such as butter, awesome milk, butter hard candy, milk, and also cheese. The major derivative of lactic acid: calcium stearoyl is utilized as a preservative. Adding 0.3%-0.5% calcium stearoyl lactylate to flour can make bread leavened, boost its volume by 30%-40%, and delay aging. When salt lactate is utilized as a flavor representative, it is used in casein plastic bleaching agent, antifreeze, hydrating agent as well as pharmaceutical manufacturing. Calcium lactate can be used as a nutritional fortifier. Ferrous lactate is used in food fortification as well as in the therapy of iron shortage anemia in medication. Lactic acid esters, consisting of methyl esters, ethyl esters, butyl esters, etc, are made use of as solvents, flavor representatives, and so on. Lactic acid and its derivatives such as sodium salt and also calcium salt are safe and risk-free food additives. Stearoyl lactate is used in emulsifiers as well as baked items; sodium lactate is utilized for intravenous injection; synthetic lactic acid is utilized instead of normally fermented lactic acid in cheese and other dairy items to acidify as well as coagulate milk or cream. These three usages increased the production of lactic acid in the United States. With the advancement of the food market, the prospective market for lactic acid is big.
  2. Poly l Lactic Acid is a vital sour representative and has a details astringent sour taste. It can be utilized in all kinds of food and can be made use of in small amounts according to production demands. It additionally has a solid bactericidal result, which can stop the growth of assorted germs.
  3. Poly l Lactic Acid is utilized as speculative reagents, flavors, chemicals, plasticizers as well as binders, and also in the pharmaceutical industry.
  4. Poly l Lactic Acid is primarily used in spices, food and also beverage sectors, as well as is additionally a raw material for pharmaceutical, chemical, natural leather, printing and also coloring markets.
  5. Poly l Lactic Acid food acids and flavors, preservatives, preparation of lactate, plasticizers, complexometric titration analysis, magnesium and aluminum, determination of carbon dioxide binding capacity in plasma, determination of copper and zinc.

Preparation of Poly l Lactic Acid

Poly l Lactic Acid can be produced by chemical or microbial fermentation. The chemical method uses petroleum-based chemicals as raw materials for synthesis, so it is affected by crude oil supply and price fluctuations (the crude oil price range from 2008 to 2014 is 40 to 145 US dollars / barrel). Another disadvantage of chemical methods is that usually only racemic DL-Poly l Lactic Acid can be synthesized, and its application in food and beverages is limited due to the metabolism of D-lactic acid in the human body. Polylactic acid requires lactic acid monomers with extremely high chemical purity and high optical purity. Usually, the content of L-lactic acid must be greater than 96% to 99% (that is, D-lactic acid is less than 1% to 4%). Therefore, chemically racemic lactic acid is required. It does not meet the requirements of general polylactic acid materials, and can only be used in some chemical fields that do not require optical purity, such as metal plating, detergents, etc., so the market is very small. At present, the only manufacturer of chemically synthesizing lactic acid is Japan’s Musashino. Most of the other manufacturers use microorganisms to anaerobic fermentation of carbohydrates (such as sucrose or starch sugar) to produce acid. One molecule of glucose can be converted into two molecules of lactic acid through glycolysis, and the theoretical conversion rate is 100%, but the actual fermentation yield can only reach about 90%. The difference in the production conditions of D-lactic acid or L-lactic acid is mainly in the bacterial species and fermentation conditions. There is not much difference between the recovery and purification process, but it is necessary to avoid extreme conditions (such as high temperature in the purification process) for D-lactic acid and L-lactic acid. Under the interconversion racemic. During anaerobic fermentation, the pH of the fermentation broth

The pH value will decrease with the formation of lactic acid. Calcium hydroxide or calcium carbonate must be added to neutralize the lactic acid and maintain optimal pH fermentation conditions. After fermentation, the bacteria and impurities are separated by filtration and centrifugation, which can be used as feed additives. After the fermentation broth is cooled, calcium hydroxide and lactic acid are neutralized to form calcium lactate precipitation, which must be dissolved with sulfuric acid to extract lactic acid. This process will generate calcium sulfate precipitation by-products. After filtration and separation, the generated solid waste can be used as gypsum. Construction sector. The crude lactic acid liquid extracted by this process still contains a lot of soluble proteins, sugars, salts, miscellaneous acids, etc., which must be purified and removed. Food-grade Poly l Lactic Acid allows a small amount of soluble impurities, which can be purified by resin adsorption, decolorized by activated carbon, membrane separation or concentrated by evaporation, so that the concentration of lactic acid can reach 80% to 88% of the general commercial level (including 12% to 20% of water). Such as concentrated Poly l Lactic Acid to 92% to 93%, it is more suitable for polymerization application, but its viscosity increases, and it will exist in the form of dimer or trimer at room temperature or low temperature.

Heat-resistant or polymerized lactic acid requires high chemical purity, so the soluble impurities in crude Poly l Lactic Acid must be completely removed by esterification or molecular distillation. The esterification distillation method reacts methanol and lactic acid to form a relatively volatile methyl lactate, and then purifies by distillation. The obtained methyl lactate is hydrolyzed into lactic acid and methanol, and then the methanol is separated by distillation to obtain Poly l Lactic Acid. The energy consumption of molecular distillation method is relatively large, and it can be concentrated by vacuum evaporation or nanofiltration before distillation, and the residual dark waste liquid of distillation can be used as a feed additive. To obtain lactic acid with an optical purity greater than 99.9%, the optical purity can be further improved by crystallization. The purified lactic acid can be neutralized by adding alkali to make a salt solution such as sodium lactate or calcium lactate; or by evaporation, spray drying, crystallization, granulation, drying, to form solid lactate; or by adding methanol or ethanol, etc., esterification to generate Lactate. After dehydration and purification of Poly l Lactic Acid, anhydrous lactide can be generated for polymerization into polylactic acid, or other copolymers. Industrial-grade polylactic acid must use lactic acid with high optical purity to improve crystallinity, heat resistance and physical and mechanical strength.

Poly l Lactic Acid Production Method

There are two types of industrial production of Poly l Lactic Acid: fermentation method and synthetic method, each accounting for about 60%. 1 The fermentation method uses rice or dry potato flour as raw materials, and is gelatinized at 120 ° C through steam. The gelatinized liquid is saccharified under the action of saccharifying enzyme at 51~53℃. Poly l Lactic Acid can be obtained by fermentation of glucose. (1) The product of lactobacillus fermentation by lactobacillus is generally DL-lactic acid. The saccharified liquid is heated to 90~95℃ for 1~2h sterilization with steam, cooled to 50℃, and then inoculated with Lactobacillus for fermentation. The fermentation temperature is controlled at 48~50℃; ventilation and stirring; the pH value is controlled at 5.5~6.0, calcium carbonate is added to the medium, and calcium carbonate is also added in batches during the fermentation process to adjust the pH value>5.0. The fermentation cycle is 3 to 4 days. (2) Rhizopus fermented Rhizopus is also Poly l Lactic Acid producing bacteria. Although its theoretical sugar-acid conversion rate is low (75%), it is easy to obtain high-purity L-Poly l Lactic Acid. (3) Extraction of Poly l Lactic Acid from fermented Poly l Lactic Acid is not easy to crystallize, and the calcium salt method is generally used for extraction in China. That is, after the fermentation is completed, the fermentation broth is neutralized with calcium hydroxide to a pH value of 11-12, and press-filtered while hot (>80°C), the filtrate is added with a magnesium chloride precipitant, and the supernatant is concentrated to a relative density of 1.098-1.115. Then stand for crystallization and filter to obtain loose calcium lactate crystals. Calcium lactate was melted with steam, acidified with sulfuric acid, decolorized with activated carbon, and vacuum filtered to obtain a Poly l Lactic Acid solution containing about 10% after standing for 6 hours. Concentrate once to a relative density of 1.098, use ion exchange resin to remove calcium and magnesium ions, and then concentrate twice, decolorize and filter to obtain the finished product of lactic acid. 2 Synthetic methods Chemical synthesis includes acetaldehyde method and acrylonitrile method, and the obtained Poly l Lactic Acid is DL. Poly l Lactic Acid. (1) The acetaldehyde method takes acetaldehyde and hydrocyanic acid as raw materials to react to generate lactonitrile, which is hydrolyzed to obtain crude lactic acid, and the crude Poly l Lactic Acid is then hydrolyzed to obtain lactic acid through ethanol esterification: acetaldehyde and cold hydrocyanic acid are continuously fed into the reaction Lactonitrile is generated by the device, which is then pumped into the hydrolysis kettle, and water and sulfuric acid are added to catalyze hydrolysis to obtain lactic acid; after esterification with ethanol, ethyl lactate is obtained by rectifying distillate; finally, it is sent to the concentration tank for heating and decomposing to obtain refined lactic acid. (2) Acrylonitrile method hydrolyzed acrylonitrile to obtain crude lactic acid, and then hydrolyzed to obtain lactic acid after methanol esterification: acrylonitrile was sent to the reactor, and hydrolyzed under the catalysis of sulfuric acid to generate a mixture of lactic acid and ammonium hydrogen sulfate. The mixture enters the esterification reactor and is esterified with methanol. After separating out ammonium hydrogen sulfate, the crude ester is sent to the rectification tower, and the refined ester is obtained at the bottom of the tower. The refined ester is then sent to the distillation tower for thermal decomposition to obtain dilute Poly l Lactic Acid. Finally, the product is obtained by vacuum concentration.

About Us

The production base is located in Zhangqiu chemical industry park and Tai’an high-tech chemical industry park. laboratory and workshop in strict accordance with the GMP standard and the product fit national ISO9001 and ISO2000 standards.

“Zhishang” products are exported to Europe, North and South America, the Middle East, Asia Pacific and Africa area, so as to establish a long-term and stable cooperation relationship with customer in the world.

Company Info
  • Business Type: Manufacturer
  • Product Range: Additive , Chemical Auxiliary & Catalyst , Organic Chemicals
  • Products/Service: Organic Intermediate,Inorganic Chemistry, APIs, Dyestuffs And Pigments, Fragrance And Spices, Food Additives
  • Total Employees: 51~100
  • Capital (Million US $): 10000000RMB
  • Year Established: 2016
Production Capacity
  • No. of Production Lines : 8
  • No. of QC Staff : 5 -10 People
  • OEM Services Provided : yes
  • Factory Size (Sq.meters) : 3,000-5,000 square meters
  • Certificate: ISO9001 , CE , GMP , API , MSDS
  • Factory Location : Diao Town Industry Park, Zhangqiu City, Jinan City, Shandong Province, China.


Pre-Sales Service

* Prompt reply and 24 hours online, professional team to provide best price and high quality product.

* Sample testing support.

* Every batch of products will be tested to ensureits quality.

*The packing also can be according the customers` requirment.

*Any inquiries will be replied within 24 hours.

*we provide Commerical Invoice, Packing List, Bill of loading, COA , Health certificate and Origin certificate. If your markets have any special requirements, let us know.


After-Sales Service

*The fact of logistics information monitoring.

* Any questions about the product can be consulted at any time.

*Product has any problem can return.


Do you accept sample order?

We will make samples before mass production, and after sample approved, we’ll begin mass production. Doing 100% inspection during production, then do random inspection before packing.



You can get free samples for some products,you only need to pay the shipping cost or arrange a courier to us and take the samples. You can send us your product specifications and requests,we will manufacture the products according to your requests.

What’s your MOQ?

Our MOQ is 1kg. But usually we accept less quantity such as 100g on the condition that sample charge is 100% paid.

Do you supply product report?

Yes. We’ll give you product analysis report before shipping.

  Is there a discount?

Different quantity has different discount.


1. ≤50kg, Express delivery recommended, usually called as DDU service;

2. ≤500kg, Air shipping recommended, usually called as FOB, CFR, or CIF service;

3. >500kg, sea shipping recommended, usually called as FOB, CFR, or CIF service;

4. For high value products, please select air shipping and express delivery for safe.

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