95-96-5

Basic information

• Product Name: DL-Lactide
• Synonyms: 2,5-dimethyl-3,6-dioxo-1,4-dioxane;2,5-dioxo-3,6-dimethyl-1,4-dioxane;2-hydroxy-propanoicacibimol.cyclicester;3,6-diketo-2,5-dimethyl-1,4-dioxane;3,6-Dimethyl-2,5-dioxo-1,4-dioxane;3,6-dimethyl-p-dioxane-2,5-dione;3,6-dimethyl-p-dioxane-5-dione;5-dione,3,6-dimethyl-4-dioxane-2
• CAS NO: 95-96-5
• Molecular Formula: C₆H₈O₄
• Molecular Weight: 144.13
• EINECS: 202-468-3
• Product Categories: Dioxanes;Dioxanes & Dioxolanes;Functional Materials;Lactones & Lactides (for High-Performance Polymer Research);Reagent for High-Performance Polymer Research;Biodegradable Polymer Monomers;Building Blocks;Carbonyl Compounds;Chemical Synthesis;Lactones;Materials Science;Monomers;Organic Building Blocks;Polymer Science
• Mol File: 95-96-5.mol
• Article Data: 25

Chemical Properties

• Melting Point: 116-119 °C
• Boiling Point: 142 °C8 mm Hg(lit.)
• Flash Point: 180°C
• Appearance: White/Crystalline Powder
• Density: 1.186 g/cm³
• Vapor Pressure: 0.311Pa at 25℃
• Storage Temp.: Refrigerator (+4°C)
• Solubility: Soluble in chloroform and methanol. Slightly soluble in benzene.
• Water Solubility: 16.3g/L at 20℃
• Sensitive: Moisture Sensitive
• BRN: 82121
• CAS DataBase Reference: DL-Lactide(CAS DataBase Reference)
• NIST Chemistry Reference: DL-Lactide(95-96-5)
• EPA Substance Registry System: DL-Lactide(95-96-5)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38-36
• Safety Statements: 26-37/39
• WGK Germany: 2
• RTECS: JH1100000
• TSCA: Yes
• Hazardous Substances Data: 95-96-5(Hazardous Substances Data)

Usage

Uses

Different sources of media describe the Uses of 95-96-5 differently. You can refer to the following data:
1. DL-Lactide is used to produce 2-hydroxy-propionic acid 1-(1-phenyl-ethoxycarbonyl)-ethyl ester. It acts as an important raw material and an intermediate used in organic synthesis, pharmaceuticals, agrochemicals and dyes. It is involved in enzymatic alcoholysis to produce both alkyl (R)-lactates and alkyl (S,S)-lactyllactates.DL-Lactide is often used as a protective layer in wound coatings, or as anchors, screws or mesh in surgery, since it degrades in about six months to the innocuous lactic acid.
2. Enzymatic alcoholysis of this racemic lactide catalyzed by commercial Novozym? 435 produces both alkyl (R)-lactates and alkyl (S,S)-lactyllactates in good yield and high enantiopurity.
3. DL-Lactide is used to produce 2-hydroxy-propionic acid 1-(1-phenyl-ethoxycarbonyl)-ethyl ester. It acts as an important raw material and an intermediate used in organic synthesis, pharmaceuticals, agrochemicals and dyes. It is involved in enzymatic alcoholysis to produce both alkyl (R)-lactates and alkyl (S,S)-lactyllactates.

Chemical Properties

White crystalline powder

General Description

3,6-Dimethyl-1,4-dioxane-2,5-dione (or rac-lactide), is the 50:50 racemic mixture of D- and L-Lactide. Rac-lactide is a lactone derived from lactic acid that has attracted great interest in academia and commercial applications, as it is derived from abundant renewable resources. Rac-lactide can be ready polymerized via ring-opening polymerization, using a variety of metal or organocatalysts, yielding poly(D,L-lactide). While the resulting polymer is generally amorphous, the use of stereospecific catalysts can lead to heterotactic PLA, which exhibits some degree of crystallinity.

Flammability and Explosibility

Nonflammable

InChI:InChI=1/C6H8O4/c1-3-5(7)10-4(2)6(8)9-3/h3-4H,1-2H3

Upstream product

• 547-64-8 methyl lactate 
• 13076-19-2 (3R,6S)-3,6-dimethyl-1,4-dioxane-2,5-dione 
• 849585-22-4 LACTIC ACID 
• 515-98-0 Ammonium lactate 
• 814-80-2 calcium lactate 
• 4511-42-6 L,L-dilactide 
• 78024-33-6 2-(2-lactoyloxy-propionyloxy)-propionic acid 
• 65002-62-2 2-lactoyloxy-propionic acid ethyl ester 
• 100053-90-5 lactic acid trimer ethyl ester 
• 673502-34-6 5-acetyl-3,6-dimethyl-2,3-dihydro-1,4-dioxin-2-one 
• 10326-41-7 D-Lactic acid 
• 79-33-4 L-Lactic acid 
• 97-64-3 ethyl 2-hydroxypropionate 

Downstream Products

• 598-81-2 (+/-)-lactamide 
• 958298-96-9 (N,N'-bis(2,6-diisopropylphenyl)(tert-butyl)amidinato)tin(II)(OCH(Me)C(O)OCH(Me)C(O)OCHMe₂) 
• 600-14-6 2,3-Pentanedione 
• 535-17-1 2-acetoxypropionic acid 
• 75-07-0 acetaldehyde 
• 79-10-7 acrylic acid 
• 13076-19-2 (3R,6S)-3,6-dimethyl-1,4-dioxane-2,5-dione 
• 70022-27-4 benzyl dilactate 
• 598-72-1 2-Bromopropionic acid 
• 814-80-2 calcium lactate 
• 7512-80-3 O-acetyl-lactyllactic acid ethyl ester 
• 2051-96-9 benzyl lactate 

Relevant articles and documents

A study on highly concentrated lactic acid and the synthesis of lactide from its solution

Lactic acid is an important platform compound used as raw material for the production of lactide and polylactic acid. However, its concentration and composition distribution are not as simple as those of common compounds. In this work, the mass concentration distribution of highly concentrated lactic acid is determined by back titration. The components of highly concentrated lactic acid, crude lactide, and polymer after the reaction are analyzed by HPLC. Different concentrations of lactic acid solution were prepared for the synthesis of lactide and its content in the product was determined by 1H NMR analysis. We found that lactide is more easily produced from high-concentration lactic acid solution with which the condensed water is easier to release. Hence, the removal of condensed water is crucial to the formation of lactide, although it is not directly formed by esterification of two molecules of lactic acid.

METHOD FOR SYNTHESIZING LACTIDE BY MEANS OF CATALYSIS OF LACTID ACID

The present invention relates to a method for the catalytic synthesis of lactide from lactic acid. The method relates to the synthesis of lactide from lactic acid under the catalysis of a zinc oxide nanoparticle aqueous dispersion as a catalyst. The present invention has four technical characteristics: I. the zinc oxide nanoparticle aqueous dispersion catalyst has a sufficient surface area, and the size of nanoparticles is merely 30-40 nm, providing a sufficient contact area between the substrate (lactic acid) and the catalyst; II. the new catalyst has a milder catalytic effect on polymerization, allowing the molecular weight distribution of a prepolymer within a range of 400-1500 g/mol, which is advantageous for depolymerization to proceed; III. the new catalyst is stable, thus avoiding oxidation or carbonization in a high temperature reaction; and IV. the new catalyst has a low toxicity and a small threat to human health.

PREPARATION METHOD FOR LACTIDE

The present invention relates to a method for producing lactide, which comprises the following steps: a first temperature rising and depressurization step for depressurization after raising a temperature of lactic acid up to 160-180anddeg;C; a second temperature rising and depressurization step for adding a reaction catalyst into a product obtained in the first temperature rising and depressurization step, raising the temperature up to 180-210anddeg;C at the rate of 1-10 anddeg;C/min, and depressurizing down to 0.001-1 torr at the rate of 5-20 torr/min; and a lactide extraction step for inserting the product obtained in the second temperature rising and depressurization step into a falling film reactor.COPYRIGHT KIPO 2017