Preparation method of nano polylactic acid

A technology of polylactic acid and nanotechnology, applied in the field of nanomaterials, can solve the problems of increased process cost, complicated process, and poor particle distribution uniformity of nano-polylactic acid

Pending Publication Date: 2021-06-11
SUZHOU FIBER EXAMINATION INST +1
View PDF0 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

With the development of technology, more and more attention has been paid to nano-polymer particles, but in the process of preparing ultra-fine particles of polylactic acid, the particle distribution uniformity of nano-polylactic acid is poor, and the process is extremely complicated, resulting in a significant increase in process costs

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

[0015] A preparation method of nano polylactic acid, comprising the steps of:

[0016] Step 1, add polylactic acid to 1L of dichloromethane, seal and reflux for 10 minutes to obtain a polylactic acid solution, the concentration of polylactic acid in dichloromethane is 100g / L, the temperature of sealed reflux is 30°C, and the pressure is 0.5 MPa, the reflux rate is 2mL / min;

[0017] Step 2, uniformly spray the polylactic acid solution in a constant temperature reaction kettle, and let it stand at a constant temperature for 20 minutes to obtain a suspension; the spray area of ​​the uniform spray is 20cm 2 , distilled water is added in the constant temperature reactor, and the temperature of the distilled water is 50°C; the temperature of the constant temperature standing is 60°C, and the pressure is 0.2MPa;

[0018] Step 3, using constant temperature nitrogen to purge the reactor, and adopting a two-gradient decompression cooling method to recover dichloromethane, and the dichl...

Embodiment 2

[0022] A preparation method of nano polylactic acid, comprising the steps of:

[0023] Step 1: Add polylactic acid to 1L of dichloromethane, seal and reflux for 20 minutes to obtain a polylactic acid solution, the concentration of polylactic acid in dichloromethane is 100-200g / L, the temperature of sealed and reflux is 50°C, the pressure is 0.8MPa, and the reflux rate is 5mL / min;

[0024] Step 2, uniformly spray the polylactic acid solution in a constant temperature reaction kettle, and let it stand at a constant temperature for 30 minutes to obtain a suspension; the spray area of ​​the uniform spray is 50cm 2 , distilled water is added in the constant temperature reactor, and the temperature of the distilled water is 60°C; the temperature of the constant temperature standing is 80°C, and the pressure is 0.3MPa;

[0025] Step 3, using constant temperature nitrogen to purge the reactor, and adopting a two-gradient decompression cooling method to recover dichloromethane, and th...

Embodiment 3

[0029] A preparation method of nano polylactic acid, comprising the steps of:

[0030] Step 1, add polylactic acid to 1L of dichloromethane, seal and reflux for 15 minutes to obtain a polylactic acid solution, the concentration of polylactic acid in dichloromethane is 150g / L, the temperature of sealed reflux is 40°C, and the pressure is 0.7 MPa, the reflux rate is 4mL / min;

[0031] Step 2, uniformly spray the polylactic acid solution in a constant temperature reaction kettle, and let it stand at a constant temperature for 25 minutes to obtain a suspension; the spray area of ​​the uniform spray is 40cm 2 , distilled water is added in the constant temperature reactor, and the temperature of the distilled water is 55°C; the temperature of the constant temperature standing is 70°C, and the pressure is 0.2MPa;

[0032] Step 3, using constant temperature nitrogen to purge the reactor, and adopting a two-gradient decompression cooling method to recover dichloromethane, and the dichl...

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 invention belongs to the field of nano materials, and particularly relates to a preparation method of nano polylactic acid, which comprises the following steps: step 1, adding polylactic acid into dichloromethane, and carrying out sealed reflux reaction for 10-20 minutes to obtain a polylactic acid dissolved solution; step 2, uniformly spraying the polylactic acid dissolved solution into a constant-temperature reaction kettle, and conducting standing for 20-30 minutes at a constant temperature to obtain a turbid liquid; step 3, purging the reaction kettle with constant-temperature nitrogen, recovering dichloromethane in a two-gradient reduced-pressure cooling mode, wherein the dichloromethane is used for dissolution in the step 1; and step 4, filtering the turbid liquid in the step 2 to obtain solid particles, repeatedly washing the solid particles with distilled water, and drying the solid particles to obtain nano lactic acid particles. According to the invention, the process difficulty of a nano polymer is solved, and the change of polylactic acid in different solvents is utilized to form a rapid spray dispersion effect, so that the effect of polymer nanocrystallization is achieved.

Description

technical field [0001] The invention belongs to the field of nanometer materials, and in particular relates to a preparation method of nanometer polylactic acid. Background technique [0002] Nanomaterials refer to materials that have at least one dimension in the three-dimensional space that is in the range of nanometers or are composed of them as basic units. This refers to the change in properties caused by the sharp increase in the ratio of the number of atoms on the surface of nanocrystal grains to the total number of atoms as the particle size decreases. With the development of technology, more and more attention has been paid to nano-polymer particles, but in the process of preparing ultra-fine particles of polylactic acid, the particle distribution uniformity of nano-polylactic acid is poor, and the process is extremely complicated, resulting in a significant increase in process costs. Contents of the invention [0003] Aiming at the problems in the prior art, the...

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
IPC IPC(8): C08J3/12C08L67/04
CPCC08J3/122C08J2367/04
Inventor 朱兰李婷高正
Owner SUZHOU FIBER EXAMINATION INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products