Supercharge Your Innovation With Domain-Expert AI Agents!

Method for protecting amino end groups in polybenzimidazole high-molecular material

A technology of polybenzimidazole and polymer materials, which is applied in the field of protection of terminal amino groups, can solve the problems affecting the stability and service life of materials, and achieve the effect of high yield and easy reaction

Inactive Publication Date: 2011-11-16
SHANDONG UNIV OF TECH
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] Studies have found that the two adjacent terminal amino groups are easily oxidized under high temperature and oxidative conditions, thereby degrading the polymer molecule from one end, which affects the stability and service life of this type of material

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
  • Method for protecting amino end groups in polybenzimidazole high-molecular material
  • Method for protecting amino end groups in polybenzimidazole high-molecular material
  • Method for protecting amino end groups in polybenzimidazole high-molecular material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0053] The reaction equation is as follows:

[0054]

[0055] In the formula: (1) is polybenzimidazole; (2) is urea; (3) is PBI whose terminal amino group is protected (that is, a polymer that generates terminal benzimidazolone)

[0056] In a 250mL four-necked flask equipped with a stirrer, a reflux condenser, a thermometer, and a dropping funnel, polybenzimidazole (15g) to be protected, urea (18~28g), 70mL of dimethylacetamide, and 70mL of dimethylacetamide were added successively. heating. Stir under the protection of nitrogen, heat the oil bath to 100 ℃ ~ 108 ℃, add 95% sulfuric acid dropwise, maintain the pH value of the reaction solution between 5 and 6, and react at 100 ℃ ~ 180 ℃. 4.5 g of urea was added every 1 h, and the reaction was continued for 6 h. The reaction mixture was slowly poured into water for spinning, and washed with deionized water for 3 to 5 times. The solid polymer was pulverized and washed with deionized water for 3 times, and the PBI (light yell...

Embodiment 2

[0057] [Example 2] Microwave-assisted solid-phase synthesis

[0058] A microwave-assisted solid-phase synthesis method was used. In a three-necked flask equipped with a condenser and protected by an inert gas, add the polybenzimidazole to be protected, urea, water and concentrated sulfuric acid (the amount added is the same as in Example 1), first feed the protective gas nitrogen for 10 min, and under nitrogen protection Under the microwave intermittent heating reaction, each heating 3mim, intermittent 10min, after the temperature drops, add 5g urea. Such an intermittent reaction is performed 6 to 8 times. The reaction solution was slowly poured into water for spinning. Other processing methods are the same as in Example 1.

Embodiment 3

[0060] With the method of embodiment 1, just replace urea with equimolar substituted urea, thiourea and substituted thiourea to obtain other protection situations in the general formula.

[0061] The polybenzimidazole can be of any structure, but the amount of urea added during the PBI reaction of different structures is different. For example, the amount of urea required by general long-chain PBI is 2 to 4 times the amount of its terminal amino groups. The hyperbranched PBI has a large amount of urea due to its large amount of terminal amino groups. The amount of urea is 2 to 5 times that of its terminal amino group. If the quality of PBI is used as a benchmark, the amount of urea used in hyperbranched PBI is 5 to 10 times that of chain PBI.

[0062] The solvent can be selected from dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone and the like.

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
glass transition temperatureaaaaaaaaaa
tensile strengthaaaaaaaaaa
elongationaaaaaaaaaa
Login to View More

Abstract

The invention relates to a method for protecting amino end groups in polybenzimidazole high-molecular material. The method is characterized in that under the protection of nitrogen and the effect of catalyst, polybenzimidazole reacts with protective agent and solvent, wherein the protective agent is carbamide, thiocarbamide or carbamidine compound, and the solvent is dimethylacetylamide, dimethylsulfoxide or N-methylpyrrolidone. The method can ensure that the amino end groups can form a stable structure, so that the amino end groups cannot be reduced as amino groups.

Description

technical field [0001] The invention relates to a method for protecting terminal amino groups in polybenzimidazole polymer materials. Background technique [0002] Polybenzimidazole (PBI) first appeared in US patents in 1959, aromatic PBI polymers were reported by H. Vogel in 1961, and the US Hoechst Celanese company put PBI membrane products on the US market in 1988. A polymer containing benzimidazole repeating units in the main chain of PBI polymers, which is a yellow to tan amorphous powder. The glass transition temperature of aromatic polybenzimidazole is 480°C, there is basically no weight loss below 500°C in nitrogen, and the maximum decomposition temperature exceeds 600°C. Excellent low temperature performance, not brittle at -196 ℃. The tensile strength of the PBI film is 110MPa, the tensile modulus is 2.65GPa, and the elongation is 11%. PBI is non-flammable in air and burns slowly in oxygen. Resistant to strong acids, alkalis and organic solvents, it is the only...

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): C08G73/18
Inventor 李忠芳王素文董飞龙于先进
Owner SHANDONG UNIV OF TECH
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

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

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com