Monocyclic benzoxazine intermediate with low viscosity and a plurality of functional groups and synthesis method thereof

A benzoxazine and multi-functional technology, which is applied in the field of ring-opening polymerization and its polymer preparation, can solve the problems of monocyclic benzoxazine intermediates that cannot be cross-linked and cured, and have low mechanical and thermal properties.

Inactive Publication Date: 2010-06-23
SHANDONG UNIV
View PDF0 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] Monocyclic benzoxazine intermediates without functional substituents cannot be cross-linked and cured, and only oligomers can be obtained by polymerization. Their mechanical properties and thermal properties are not high, so they have not received enough attention. They are often used as polybenzoxazines. Reactive diluent in oxazine system

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
  • Monocyclic benzoxazine intermediate with low viscosity and a plurality of functional groups and synthesis method thereof
  • Monocyclic benzoxazine intermediate with low viscosity and a plurality of functional groups and synthesis method thereof
  • Monocyclic benzoxazine intermediate with low viscosity and a plurality of functional groups and synthesis method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0075] Embodiment 1, 3-allyl-6-cyano-3,4-dihydro-2H-1, the synthesis of 3-benzoxazine (NB-ala):

[0076] Add 10.0g of p-cyanophenol, 6.5mL of allylamine, 1ml of triethylamine, and 40mL of anhydrous dioxane to a 100mL three-neck flask in sequence, stir to mix, and cool down with an ice-water bath. Slowly add 5g of paraformaldehyde, gradually raise the temperature to 90°C, and react at this temperature for 4h to obtain a yellow benzoxazine intermediate solution. The reaction mixture was rotary evaporated, and the obtained crude product was recrystallized with anhydrous ether to obtain pale yellow crystals with a yield of 67%.

[0077] Elemental Analysis: C 12 h 12 N 2 O, theoretical value %: C, 72.00%; H, 6.00%; N, 14.00%. Analytical value: 0, 71.43%; H, 5.92%; N, 13.77%. 1 H NMR (CDCl 3 , 300MHz, δ): 3.34ppm (d, N-CH 2 -C), 3.99ppm(s, Ar-CH 2 -N), 4.94ppm (s, O-CH 2 -N), 5.19ppm (m, =CH 2 ), 5.86ppm (m, -CH=), 6.81-7.42ppm (Ar-H). FTIR (KBr) v: 1028cm -1 (C-O-C symmet...

Embodiment 2

[0078] Embodiment 2,3-allyl-6-formyl-3,4-dihydro-2H-1, the synthesis of 3-benzoxazine (FB-ala)

[0079] Add 10.2g of p-hydroxybenzaldehyde, 6.5mL of allylamine, 1ml of triethylamine, and 40mL of anhydrous dioxane into a 100mL three-necked flask in sequence, stir to mix and dissolve, and cool down with an ice-water bath. Slowly add 50 g of paraformaldehyde, gradually raise the temperature to 90° C., and react at this temperature for 4 hours to obtain a yellow benzoxazine intermediate solution. The reaction mixture was rotary evaporated, and the obtained crude product was dissolved in 30mL of dichloromethane, washed several times with 1N NaOH aqueous solution and deionized water, and left to separate layers. After the dichloromethane phase was concentrated, column chromatography gave a light yellow transparent Liquid, 72% yield.

[0080] Elemental Analysis: C 12 h 13 NO 2 , Theoretical %: C, 70.94%; H, 6.40%; N, 6.90%. Analytical values: C, 70.31%; H, 6.92%; N, 6.73%. 1 H N...

Embodiment 3

[0081] Example 3, Synthesis of 3-allyl-6-cyano-3,4-dihydro-2H-1,3-benzoxazine (NB-ala): Add 59.5g of para Cyanophenol, 37.5mL allylamine, 6ml triethylamine, 200mL absolute ethanol, stirred and mixed, and cooled with an ice-water bath. Slowly add 30 g of paraformaldehyde, gradually raise the temperature to reflux, and react at reflux temperature for 4 hours to obtain a yellow benzoxazine intermediate solution. The reaction mixture was rotatively evaporated, and the obtained crude product was recrystallized with anhydrous ether to obtain pale yellow crystals with a yield of 72%.

[0082] Elemental Analysis: C 12 h 12 N 2 O, theoretical value %: C, 72.00%; H, 6.00%; N, 14.00%. Analytical value: C, 71.43%; H, 5.92%; N, 13.77%. 1 H NMR (CDCl 3 , 300MHz, δ): 3.34ppm (d, N-CH 2 -C), 3.99ppm(s, Ar-CH 2 -N), 4.94ppm (s, O-CH2-N), 5.19ppm (m, =CH 2 ), 5.86ppm (m, -CH=), 6.81-7.42ppm (Ar-H). FTIR (KBr) v: 1028cm -1 (C-O-C symmetrical telescopic), 1237cm -1 (C-O-C asymmetric tel...

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
viscosityaaaaaaaaaa
viscosityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a monocyclic benzoxazine intermediate with low viscosity and a plurality of functional groups, a preparation method thereof and application thereof in the preparation of high-temperature resistant resin. The process method is simple, practicable, and suitable for industrial production in most of factories; a cross-linked polymer prepared by the benzoxazine intermediate has very high vitrification conversion temperature (Tg is larger than 250 DEG C), is available to high-temperature resistant materials used in the temperature more than 250 DEG C, and has higher carbon residue rate (800 DEG C, N2, PNB-ala: 57%; 800 DEG C, N2, FB-ala: 61%) and a certain application prospect in terms of the preparation of carbon materials and ablation resistant materials.

Description

technical field [0001] The present invention relates to a benzoxazine intermediate and a synthesis method thereof, in particular to a novel benzoxazine intermediate—a low-viscosity, multi-reactive group-containing, monocyclic benzoxazine intermediate and its Synthetic methods, and the ring-opening polymerization of said intermediates and the preparation of polymers thereof. The invention belongs to the technical field of preparation of novel monocyclic benzoxazine intermediates and preparation of high temperature resistant resins. Background technique [0002] Monocyclic benzoxazine intermediates without functional substituents cannot be cross-linked and cured, and only oligomers can be obtained by polymerization. Their mechanical properties and thermal properties are not high, so they have not received enough attention. They are often used as polybenzoxazines. Reactive diluent in oxazine systems. The emergence of bicyclic benzoxazine intermediates in the 1990s has changed...

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): C07D265/14C08G73/06
Inventor 鲁在君王登霞张洪春高星张廷廷
Owner SHANDONG UNIV
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