Method for synthesizing polybutylene terephthalate

A polybutylene terephthalate and butanediol technology, which is applied in the field of polyester production, can solve the problems of reduced catalytic efficiency, easy deposition of hydrolyzates and blocked pipelines, etc.

Active Publication Date: 2014-03-26
CHINA PETROLEUM & CHEM CORP +1
View PDF8 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] Due to the characteristics of titanate compounds, titanate catalysts are very easy to react with the water generated in the reaction

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

example 1

[0023] Example 1: Add 283.9 grams of isopropyl titanate and 90 grams of 1,4-butanediol in a 500ml round bottom flask, start stirring and heating in a water bath, control the reaction temperature at 50-80°C, and under reduced pressure (vacuum degree 40~60mmHg) The reaction continues for about 2 hours, and the distillate isopropanol reaches a theoretical amount of 120 grams at this time, and finally an orange-red viscous liquid is obtained, which is a chelating titanium catalyst.

example 2

[0024] Example 2: Add 340 grams of tetrabutyl titanate and 90 grams of 1,4-butanediol in a 500ml round-bottomed flask, start stirring and heating in a water bath, control the reaction temperature at 55-85°C, and under reduced pressure (vacuum degree 65~90mmHg) The reaction continued for about 2 hours, at this time the distillate butanol reached a theoretical amount of 148 grams, and finally an orange-red viscous liquid was obtained, which was a chelating titanium catalyst.

[0025] Example 3: Add 283.9 grams of isopropyl titanate and 62 grams of ethylene glycol into a 500ml round bottom flask, start stirring and heating in a water bath, control the reaction temperature at 50-85°C, and under reduced pressure (vacuum degree 70-90mmHg) The reaction continued for about 2 hours. At this time, the distillate isopropanol reached a theoretical amount of 120 grams, and a red viscous liquid was obtained, which was a chelated titanium catalyst.

[0026] Example 4: Add 283.9 grams of isop...

Synthetic example 1

[0030] Add 350 grams of terephthalic acid, 320 grams of 1,4-butanediol, and 0.1477 grams of the titanium catalyst prepared in Example 1 into a 2L reactor, start stirring, replace with nitrogen three times, and perform esterification at 157-230°C under normal pressure After about 120 minutes, the reaction solution was completely transparent, and the esterification was completed. Then, the pressure was reduced and the temperature was gradually increased. After 45 minutes, the vacuum of the reactor reached 50-60 Pa, and the temperature of the reaction system was controlled at 250-265 ° C. After another 68 minutes, when the stirring power was increased by 40 When the polymerization reaction is finished, PBT can be obtained by water cooling and pelletizing, and the titanium content in PBT is about 60ppm. The intrinsic viscosity of the synthesized PBT is 0.877, the carboxyl-terminated group is 26 mol / ton, the melting point is 222.6°C, the hue L is 85.9, a-0.49, b3.7.

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

PropertyMeasurementUnit
Melting pointaaaaaaaaaa
Melting pointaaaaaaaaaa
Melting pointaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for synthesizing polybutylene terephthalate. The method comprises steps of firstly carrying out esterification between diacid and dihydric alcohol in presence of a chelate titanium catalyst at 150-230 DEG C under normal pressure, when the reaction liquid is totally transparent, gradually raising temperature of a reaction system to be 240-265 DEG C and reducing pressure to be absolute pressure of 30-300Pa, and then carrying out polycondensation so as to prepare PBT (polybutylene terephthalate) with intrinsic viscosity of 0.75-1.1, wherein the chelate titanium catalyst is prepared from organic titanate and fatty dihydric alcohol through decompression reaction at 50-90 DEG C. According to PBT prepared by the method, on the basis of not lowering general performances, the chelate titanium catalyst has stronger catalytic activity compared with traditional a titanate catalyst.

Description

technical field [0001] The invention belongs to the field of polyester production, in particular to a method for synthesizing polybutylene terephthalate. Background technique [0002] Polybutylene terephthalate (PBT for short) is a product with rapid development, rapid growth in production capacity, multiple specifications and a wide range of applications. Because PBT has heat resistance, weather resistance, chemical resistance, good electrical properties, low water absorption and good gloss, it is widely used in electronic appliances, auto parts, machinery, household products, etc. PBT products are also compatible with PE, PC, POM, PA, etc. are called the five general-purpose engineering plastics. At the same time, PBT also has important applications in the fields of fibers and films. [0003] Since the synthesis technology of PBT resin was developed on the basis of PET synthesis technology, in the initial stage of PBT resin research and development, PET resin synthesis c...

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): C08G63/183C08G63/85
Inventor 戴志彬夏峰伟魏高富
Owner CHINA PETROLEUM & CHEM CORP
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