Preparation method of polylactic acid-chitose graft copolymer

A technology of graft copolymer and chitosan, which is applied in the field of preparation of biomedical materials, can solve problems such as complicated process routes, and achieve the effect of simple synthesis method, mild reaction conditions and low energy consumption

Inactive Publication Date: 2008-10-15
NORTHWEST UNIV
View PDF1 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The process route of this

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] Weigh 0.25g chitosan (90%) and add it to 6g L-lactic acid (80%), stir at room temperature to fully dissolve it, pour the solution into a 250ml three-necked flask and add an appropriate amount (about 200ml) of dichloromethane , Azeotropic dehydration at 40°C for 2-4h in the rectification water separation device. After dehydration, 0.184g of DMAP was added to the solution. After fully dissolving, it was cooled to 0°C in an ice-water bath, and then 5.846g of DCC was added within a short period of time. A condensing reflux device was used to ensure that the volume of the reaction solution was maintained at 60 ml, and the reaction was carried out at room temperature for 24 hours.

[0016] After the reaction was finished, the white precipitate dicyclohexyl urea (DCU) generated by the reaction was removed by suction filtration, the resulting filtrate was washed 3 times with 0.5M dilute hydrochloric acid, 1-2 times with distilled water, and the organic phase after water separat...

Embodiment 2

[0018] Weigh 0.25g chitosan (50%) and add it to 6g D-lactic acid (80%), stir at room temperature to fully dissolve it, pour the solution into a 250ml three-necked flask and add an appropriate amount (about 200ml) of dichloromethane , Azeotropic dehydration at 40°C for 2-4h in the rectification water separation device. After dehydration, 0.184g of DMAP was added to the solution. After fully dissolving, it was cooled to 0°C in an ice-water bath, and then 5.846g of DCC was added within a short period of time. A condensing reflux device was used to ensure that the volume of the reaction solution was maintained at 60 ml, and the reaction was carried out at room temperature for 24 hours.

[0019] After the reaction was finished, the white precipitate dicyclohexyl urea (DCU) generated by the reaction was removed by suction filtration, the resulting filtrate was washed 3 times with 0.5M dilute hydrochloric acid, 1-2 times with distilled water, and the organic phase after water separat...

Embodiment 3

[0021] Take by weighing 0.25g chitosan (90%) and join in 6g L-lactic acid (80%), stir at room temperature and make it fully dissolve, solution is poured in the 250ml there-necked flask and adds appropriate (about 200ml) toluene, in Azeotropic dehydration at 90°C for 2-4 hours in a rectification water separation device. After dehydration, add 0.56g of AlCl to the solution 3 . A condensing reflux device was used to ensure that the volume of the reaction solution was maintained at 60ml, and the reaction was carried out at 100°C for 4h.

[0022] After the reaction, the AlCl was removed by suction filtration 3 , the resulting filtrate was washed 1-2 times with distilled water, and the organic phase after water separation was washed with anhydrous Na 2 SO 4 dry. Overnight at room temperature, filter to remove Na 2 SO 4 , the reaction solution was concentrated by rotary evaporation, poured into absolute ethanol for purification, and a white precipitate was obtained, which was ...

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 discloses a method for making polylactic acid-chitosan graft copolymer. The method comprises the following steps that: (1) the chitosan with a deacetylation between 50 and 90 percent and a molecular weight between 500 and 30000 is dissolved into a lactic acid solution; (2) a nonpolar solvent capable of forming a low-boiling point azeotrope is added into the mixture to dehydrate at the temperature of between 40 and 90 DEG C; (3) after the dehydration is finished, an organic base and a catalyst are added to react at the temperature of between 10 and 100 DEG C, the catalyst is an acid catalyst, a Lewis acid catalyst, a strong acid type positive ion-exchange resin or an N, N'- dicyclohexylamine carbimide; (4) the drying and concentrating processes are performed and the product is obtained. The synthetic method is simple, the reaction condition is moderate, and the energy consumption is low, therefore, the method is suitable for the industrial production.

Description

technical field [0001] The invention relates to a preparation method of biomedical materials, in particular to a preparation method of chitosan-polylactic acid graft copolymer. technical background [0002] Polylactic acid is a new type of biodegradable polymer material chemically synthesized from lactic acid as a monomer. It is non-toxic, non-irritating, has excellent biocompatibility, can be biodegraded and absorbed, has high strength, good plasticity, and is easy to process. forming. Polylactic acid is decomposed enzymatically in the living body, and finally forms carbon dioxide and water, and will not accumulate in vital organs, so it has become one of the most attractive materials in the medical field. However, the degradation cycle of polylactic acid materials in biomedical applications is difficult to control. The acidic degradation products easily cause aseptic inflammation and strong hydrophobicity in the body. In addition, the more important thing is the lack of a...

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): C08B37/08C08G63/91C08G63/06
Inventor 郝红李涛刘荣杰
Owner NORTHWEST UNIV
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap