Supercharge Your Innovation With Domain-Expert AI Agents!

Method for lactide synthesis from lactic acid catalysized by montmorillonite

A technology for catalyzing lactic acid and lactide with montmorillonite, which is applied in the chemical field, can solve the problem of no lactide being found, and achieve the effects of high yield, wide source of raw materials, and short time consumption

Inactive Publication Date: 2008-09-10
NORTHWEST NORMAL UNIVERSITY
View PDF2 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

So far, a particularly efficient method for the synthesis of lactide has not been found

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0017] Embodiment 1: Add 50gD in the 250ml three-necked round-bottomed flask that is equipped with thermometer, and place in magnetic stirrer, temperature rises to 60 ℃, and vacuum degree is controlled at 0.001MPa decompression distillation removes free in lactic acid. Water; after about 2.5 hours, the water is basically evaporated, add D,L-lactic acid acidified montmorillonite with 0.01% acetic acid, slowly raise the temperature to 80°C, and reduce the pressure to 1.0×10 -4 The dehydration was continued for 3 hours under MPa, and polylactic acid with low molecular weight was generated; the water condenser was replaced with an air condenser, and the round bottom flask was connected twice, the temperature was raised to 170 °C, and the pressure was raised to 6.0×10 -5 MPa, the nitrogen flow rate is controlled at 1L / min, react for 2 hours to generate crude lactide; wash the crude lactide with distilled water, recrystallize 2-5 times with ethyl acetate, and then put it in a vacuum ...

Embodiment 2

[0018] Embodiment 2: Add 50gD in the 250ml three-necked round-bottomed flask that is equipped with thermometer, and place in magnetic stirrer, temperature rises to 70 ℃, and vacuum degree is controlled at 0.005MPa decompression distillation removes free in lactic acid. Water; after about 2.5 hours, the water is basically evaporated, add D,L-lactic acid acidified montmorillonite with 0.03% phosphoric acid, slowly raise the temperature to 100°C, and reduce the pressure to 5.0×10 -4 Continue dehydration for 1 hour at MPa to generate polylactic acid with low molecular weight; replace the water condenser with an air condenser, connect the round bottom flask twice, raise the temperature to 180°C, and the pressure to 1.0×10 -4 MPa, the nitrogen flow rate is controlled at 1.5L / min, react for 6 hours to generate crude lactide; wash the crude lactide with distilled water for several times, then recrystallize with ethyl acetate for 2-5 times, and put it in a vacuum at 50°C Drying in a dr...

Embodiment 3

[0019] Embodiment 3: Add 50g D, L-lactic acid in the 250ml three-necked round bottom flask that is equipped with thermometer, and place in magnetic stirrer, temperature rises to 80 ℃, and vacuum degree is controlled at 0.005MPa Reduced pressure distillation removes in lactic acid Free water; after about 2.5 hours, the water is basically evaporated, add D,L-lactic acid acidified montmorillonite with 0.05% sulfuric acid, slowly raise the temperature to 120°C, and reduce the pressure to 7.0×10 -4 Continue dehydration at MPa for 2 hours to produce polylactic acid with low molecular weight; replace the water condenser with an air condenser, connect the round bottom flask twice, raise the temperature to 200°C, and the pressure to 3.0×10 -4 MPa, the nitrogen flow rate is controlled at 2.0L / min, react for 5 hours to generate crude lactide; wash the crude lactide with distilled water, recrystallize it with ethyl acetate for 2-5 times, and put it in a vacuum oven at 50°C Drying in mediu...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The present invention is lactide synthesizing process, which has lactic acid as material and montmorillonite acidified with different kinds of acid as catalyst and synthesizes lactide catalytically under pressure-reducing and nitrogen-introducing conditions. The present invention has the features of short reaction period, small catalyst consumption, simple catalyst preparing process, wide material source, high stability, high yield, etc.

Description

technical field [0001] The invention belongs to the field of chemistry, and relates to a preparation method of polylactic acid monomer-lactide, in particular to a method for using montmorillonite acidified with different acids as a catalyst to catalyze lactide synthesis from lactic acid. Background technique [0002] Polylactic acid is widely used in the medical field, bioengineering and other fields due to its good biocompatibility, degradability and non-toxic intermediate products. However, due to the high production cost and complicated process of polylactic acid, its application has been greatly limited. At present, the synthesis of high molecular weight polylactic acid mainly adopts the lactide ring-opening polymerization method. Therefore, the production cost of lactide directly determines whether polylactic acid can be widely used. So far, a variety of methods have been used to prepare lactide, such as: using a reduced-pressure airflow method, adding tin and zinc ca...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C07D319/12
Inventor 雷自强黄晓琴白雁斌
Owner NORTHWEST NORMAL UNIVERSITY
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com