Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method of thermotropic liquid crystal polyarylate

A technology of thermotropic liquid crystal and polyarylate, applied in the field of preparation of thermotropic liquid crystal polyarylate, can solve the problems of short reaction time and large shearing force, achieve sufficient material contact, shorten production cycle, and overcome product quality unstable effect

Inactive Publication Date: 2014-06-18
DONGHUA UNIV
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Twin-screw extruder has been widely used in polymer blending, grafting reaction, polymerization, etc. It has a series of advantages such as short reaction time, large shearing force, sufficient material contact, and simple operation. There is no relevant report on the preparation of liquid crystal polyarylate

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

[0022] Add p-acetoxybenzoic acid and 6-acetoxy-2-naphthoic acid in a molar ratio of 75:25 into the polymerization tank, keep at 180°C for 2h, then raise the temperature to 250°C for 1h, nitrogen flow rate is 50ml / min, Prepare the prepolymer; after preheating the prepolymer at 120°C for 1min, react at 200°C and 20KPa vacuum for 5min, the viscosity-increasing reaction occurs, and then continue the viscosity-increasing reaction at 300°C with a vacuum of 50KPa After 20 minutes, the liquid crystal polyester was directly extruded through a die to obtain a thermotropic liquid crystal polyarylate with a weight average molecular weight of 29,500.

Embodiment 2

[0024] Add p-acetoxybenzoic acid, terephthalic acid, and m-diacetoxybenzene in a molar ratio of 50:25:25 to the polymerization kettle, keep it at 210°C for 1.5h, then raise the temperature to 250°C and keep it for 1h, the nitrogen flow rate is 50ml / min to prepare the prepolymer; transport the prepolymer to the screw extruder, after preheating at 120°C for 1min, react at a temperature of 220°C and 20KPa vacuum for 5min, a viscosifying reaction occurs, and then at 320°C The viscosity-increasing reaction was continued for 25 minutes at a vacuum degree of 50KPa, and finally the liquid crystal polyester was directly extruded through a die to obtain a thermotropic liquid crystal polyarylate with a weight average molecular weight of 36,000.

Embodiment 3

[0026] Add p-acetoxybenzoic acid, isophthalic acid, and 1,4-diacetoxynaphthalene in a molar ratio of 60:20:20 to the polymerization kettle, keep at 200°C for 3h, then raise the temperature to 250°C for 1.5h, The nitrogen flow rate is 50ml / min, and the prepolymer is prepared; the prepolymer is transported to the screw extruder, and after being preheated at 150°C for 1min, it is reacted at a temperature of 220°C and a vacuum condition of 30KPa for 8min, and a viscosity-increasing reaction occurs. Afterwards, the viscosity-increasing reaction was continued for 20 minutes at 350° C. under a vacuum of 40 KPa, and finally the liquid crystal polyester was directly extruded through a die to obtain a thermotropic liquid crystal polyarylate with a weight average molecular weight of 36,000.

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 relates to a preparation method of thermotropic liquid crystal polyarylate. According to the invention, a prepolymer of the thermotropic liquid crystal polyarylate is prepared in a polymerization vessel through melt phase polycondensation, wherein the intrinsic viscosity of the prepolymer is 0.3-0.8 dl / g; the prepolymer is subjected to three processing stages which are preheating, low-temperature low-vacuum tackifying, and high-temperature high-vacuum tackifying, such that the thermotropic liquid crystal polyarylate with high molecular weight is prepared, wherein the intrinsic viscosity of the thermotropic liquid crystal polyarylate is 2.0-4.5 dl / g, and a molecular weight is 2.8*10<4> to 6.2*10<4>. The operation of the method is simple, and reaction conditions are easy to control. The prepared thermotropic liquid crystal polyarylate has high molecular weight, and can be prepared through continuous production. Therefore, defects of complicated steps, hard-to-control conditions, and unstable product qualities of traditional thermotropic liquid crystal polyarylate preparation methods are solved.

Description

technical field [0001] The present invention relates to a preparation method of thermotropic liquid crystal polyarylate, specifically preparing a prepolymer of thermal liquid crystal polyarylate in a polymerization kettle, and then subjecting the prepolymer to preheating, low temperature and low vacuum viscosity increasing and The invention discloses a method for preparing high-molecular weight thermotropic liquid crystal polyarylate after three-stage treatment of high-temperature and high-vacuum thickening reaction. Background technique [0002] Thermotropic liquid crystal polyarylate has a series of advantages such as high strength and high modulus, flame resistance, low water absorption, good dimensional stability, etc., and is widely used in the fields of automobiles, electronics, military industry, and protection. Since Jackson reported the first thermotropic liquid crystal polyester in the 1970s, people have launched a large-scale research on thermotropic liquid crysta...

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): C08G63/06C08G63/60C08G63/40C08G63/78C08L67/00C08L67/04C09K19/38
Inventor 王依民魏朋陈玉伟钦维民倪建华王燕萍
Owner DONGHUA UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com