Process for preparing polycarbonate with optical activity

A polycarbonate and optically active technology, applied in the field of preparing optically active polycarbonate, can solve the problems of low carbonate unit, low catalyst activity, long reaction time, etc., and achieve mild reaction conditions, high catalyst activity, and high selectivity. Effect

Inactive Publication Date: 2005-09-07
DALIAN UNIV OF TECH
View PDF9 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Japanese published patents JP 02142824 and JP 02575199 use expensive porphyrin complexes to catalyze carbon dioxide and alkylene oxide to synthesize polycarbonate, and the catalytic efficiency reaches 103~104 grams of polymer/mol catalyst, but the molecular weight of the polymer is only about 5000, and the reaction It takes more than 10 days
Chinese patent application numbers CN 89100701.6 and CN 91109459.8 disclose a bimetallic catalyst system with polymer-loaded anion coordination, which can also obtain a catalytic efficiency of 104 grams of polymer/mol catalyst, but the carrier is difficult to separate from the polycarbonate produced
In U.S. Patent US 6133402 and J.Am.Chem.Soc., (2002, 124, 14284), Coates described a highly active single-site organozinc catalyst with...

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Process for preparing polycarbonate with optical activity
  • Process for preparing polycarbonate with optical activity
  • Process for preparing polycarbonate with optical activity

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] In a stainless steel autoclave with an effective volume of 75ml, add in the following order at ambient temperature: 0.1×10 -3Molar chiral (1R, 2R)SalenCoX (see structural formula, where R 1 = R 2 = t Bu, R 3 , R 4 for -(CH 2 ) 4 -, X is 2,4-dinitrophenol oxyanion), 0.1×10 -3 Mole of tetra-n-butylammonium iodide, 0.2 mole of propylene oxide, and then pass through carbon dioxide gas and maintain a constant pressure of 2.0MPa. Control the temperature at 25°C, react under magnetic stirring for 4 hours, slowly release the unreacted carbon dioxide in the autoclave, collect the unreacted propylene oxide in a -20°C cold trap under reduced pressure, and then add a certain amount of methanol / chloroform mixture to dissolve the polymer, and then add a large amount of ether to precipitate polycarbonate. It was filtered, washed several times with ether, and dried in vacuo to constant weight to obtain 7.5 g of polypropylene carbonate as a white solid. The average molecular...

Embodiment 2

[0029] In the same apparatus as used in Example 1, under the same conditions, only tetrabutylammonium azide was used instead of tetra-n-butylammonium iodide. After reacting at 25° C. for 4 hours, 9.0 g of polypropylene carbonate was obtained, the molecular weight was 36300, the molecular weight distribution was 1.47, the carbonate unit in the polymer was higher than 99%, and the e.e. value was 45%.

Embodiment 3

[0031] In the same apparatus as used in Example 1, under the same conditions, only tetra-n-butylammonium bromide was used instead of tetra-n-butylammonium iodide. After reacting at 25° C. for 4 hours, 7.9 g of polypropylene carbonate was obtained with a molecular weight of 31,500 and a molecular weight distribution of 1.41. The carbonate units in the polymer were higher than 99%, and the e.e. value was 47%.

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 provides a method for preparing polycarbonate with optical activity by catalyzing asymmetric alternative copolymerization with racemic oxiraneic hydrocarbon and carbon dioxide, employing bi-component catalyst with chirality catalyzing the antimer of the racemic oxiraneic hydrocarbon selectively at the temperature of 0~80 DEG C, and copolymarizating with carbon dioxide to preparepolycarbonate with optical activity. The bi-component catalyst consists of host catalyst, the chirality quadridentate schiff bases metallic complexe, SalenMX; and the catalyst promoter, the salt of R1R23YX1 or (R13P)2YX1, with the proportion in moles 0.2~10:1. The proportion between catalyst and oxiranic hydrocarbon is 1:500~10000 in moles, the initial pressure of carbon dioxide is 0.1~4.0 Mpa, and the reacting for 0.5~24 hours. The method is characterized by the temperate reaction condition and the simple process; the simple synthesis of the chirality catalyst and low production cost and high reactive and suitable for industrial application.

Description

technical field [0001] The invention relates to a method for preparing optically active polycarbonate with high efficiency, convenience and mild reaction conditions. Background technique [0002] Carbon dioxide is the main gas that causes the greenhouse effect, and it is also one of the most abundant carbon sources on earth. The chemical fixation of carbon dioxide is an important research field of green chemistry. Among them, a main direction of utilizing carbon dioxide is to prepare polycarbonate by copolymerizing it with alkylene oxide under the action of a catalyst. The high polymer can be photodegraded and biodegraded; meanwhile, it has excellent performance of blocking oxygen and water. Therefore, polycarbonate can be used as engineering plastics, biodegradable non-polluting materials, disposable medical and food packaging materials, adhesives, and composite materials. Optically active polycarbonates are expected to have important applications in the high-tech field ...

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): C08G64/34
Inventor 吕小兵张英菊王辉
Owner DALIAN UNIV OF TECH
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