Efficient synthetic method of terephthalic polyester

A terephthalic acid and synthesis method technology, applied in the field of terephthalic acid-based polyester synthesis, can solve problems such as back-mixing and removal of small molecule by-products, reduce polycondensation time, reduce thermal decomposition side reactions, The effect of avoiding side effects

Pending Publication Date: 2022-02-18
CHINA TIANCHEN ENG
View PDF4 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The traditional kettle-type polycondensation reaction has the problem of back mixing, and it is not conducive to the timely removal of small molecule by-products from the reactants

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
  • Efficient synthetic method of terephthalic polyester
  • Efficient synthetic method of terephthalic polyester
  • Efficient synthetic method of terephthalic polyester

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] Embodiment 1: prepare polyethylene terephthalate (PET)

[0037] Put 1800g of terephthalic acid and 706g of ethylene glycol (excess 5mol%) into the esterification reaction kettle, add 0.3g of zinc acetate, after nitrogen replacement, heat up to 200°C and start timing, control the pressure at 0.20-0.30MpaA, the stirring rate 50 rpm. After 2 hours of reaction, the liquid output was 176g. The reaction solution was transferred to the pre-condensation reaction kettle through a gear pump, and 0.3 g of antimony ethylene glycol was added at the same time. The temperature was controlled at 230 ° C, the pressure was 5-8 kPaA, and the stirring rate was 150 rpm. After 1 hour of reaction, the liquid output was 30.0 g. The reaction solution was transferred to the finishing polycondensation horizontal reactor through a gear pump, and 0.1 g of triethyl phosphite was added at the same time, the temperature was controlled at 260° C., the pressure was 100-300 Pa, and the average residence...

Embodiment 2

[0039] Embodiment 2: prepare polybutylene terephthalate (PBT)

[0040] Put 1,800g of terephthalic acid and 1,073g of 1,4-butanediol (10mol% in excess) into the esterification reaction kettle, add 0.4g of aluminum acetate, replace with nitrogen, raise the temperature to 230°C and start timing, and control the pressure at 0.20-0.30 MPaA, stirring rate 200rpm. After 2 hours of reaction, the liquid output was 176g. The reaction solution was transferred to the precondensation reaction kettle through a gear pump, and 0.4 g of butyl titanate was added at the same time. The temperature was controlled at 240 ° C, the pressure was 5-10 kPaA, and the stirring rate was 200 rpm. After 1 hour of reaction, the liquid output was 88.0 g. The reaction solution was transferred to the finishing packed tower through a gear pump, and 0.2 g of trimethyl phosphite was added at the same time, the temperature was controlled at 260° C., the pressure was 80-200 Pa, and the average residence time was 0.5...

Embodiment 3

[0042] Example 3: Preparation of polyethylene terephthalate-1,4-cyclohexanedimethanol copolyester (PETG)

[0043] Put 1800g of terephthalic acid, 538g of ethylene glycol, and 468g of 1,4-cyclohexanedimethanol (10mol% in excess of binary total amount) into the esterification reaction kettle, add 0.3g of magnesium acetate, and after nitrogen replacement, heat up to Start timing at 200°C, control the pressure at 0.20-0.30MPaA, and stir at 100rpm. After 2 hours of reaction, the liquid output was 176g. The reaction solution was transferred to the pre-condensation reaction kettle through a gear pump, and 0.3 g of antimony ethylene glycol was added at the same time. The temperature was controlled at 230 ° C, the pressure was 5-7 kPaA, and the stirring rate was 150 rpm. After 1 hour of reaction, the liquid output was 154.0 g. The reaction solution was transferred to the finishing polycondensation horizontal reaction kettle through a gear pump, and 0.1 g of tri-cresyl phosphite was ad...

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 an efficient synthetic method of terephthalic polyester, the method comprises the following steps: taking terephthalic acid and various dihydric alcohols as raw materials, sequentially carrying out esterification, pre-polycondensation and post-polycondensation to obtain high-quality polyester, wherein the catalyst is a composite catalyst consisting of an esterification catalyst, a polymerization catalyst and a stabilizer, and is added in sections; and post-polycondensation adopts a continuous production process, so that material back-mixing is avoided, side reactions are effectively reduced, the reaction efficiency and the reaction stability are improved, and indexes such as viscosity, terminal carboxyl group content and chromaticity of the product are also obviously improved.

Description

technical field [0001] The invention belongs to the technical field of chemical synthesis, and in particular relates to a method for synthesizing terephthalic acid-based polyester. Background technique [0002] Polyester is a general term for polymers obtained by polycondensation of dibasic acids and dibasic alcohols. It is a class of plastic materials with excellent performance and a wide range of uses. For example, polyethylene terephthalate (PET), which is produced by polycondensation of terephthalic acid and ethylene glycol, can be used as a fiber for clothing weaving, or as a bottle material for packaging materials. Polybutylene terephthalate (PBT) produced by polycondensation of terephthalic acid and 1,4-butanediol is one of the five major engineering plastics and is widely used for its good heat resistance, weather resistance and fatigue resistance In automotive, electronic and electrical fields. Research hotspots in recent years - degradable plastics, mainly polyes...

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 Applications(China)
IPC IPC(8): C08G63/183C08G63/78C08G63/199
CPCC08G63/183C08G63/78C08G63/785C08G63/199
Inventor 武金丹雍学勇任丽君刘喆邴威瀚郭晓峰王聪刘新伟杨克俭
Owner CHINA TIANCHEN ENG
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