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Hexakis-2-(β-carboxyethenylphenoxy)cyclotriphosphazene: Synthesis, Properties, Modeling Structure
Pavel Yudaev1, Anastasia Konstantinova1, Vladimir Volkov2
1Mendeleev University of Chemical Technology of Russia, Miusskaya sq., 9, 125047 Moscow, Russia.
Molecules (Basel, Switzerland)
|September 28, 2023
Summary
Hexakis-2-(β-carboxyethenylphenoxy)cyclotriphosphazene (2-CEPP) was synthesized and characterized. Upon heating, 2-CEPP forms an insoluble, heat-resistant polymer via decarboxylation and polymerization.
Area of Science:
- Materials Science
- Organic Chemistry
- Polymer Chemistry
Background:
- Cyclotriphosphazenes are versatile inorganic-organic hybrid compounds with tunable properties.
- Functionalization of cyclotriphosphazenes can lead to novel materials with specific thermal and chemical behaviors.
Purpose of the Study:
- To synthesize and characterize a novel cyclotriphosphazene derivative, hexakis-2-(β-carboxyethenylphenoxy)cyclotriphosphazene (2-CEPP).
- To investigate the thermal behavior and potential applications of 2-CEPP as a precursor for heat-resistant materials.
Main Methods:
- Synthesis of 2-CEPP via condensation reaction.
- Structural characterization using NMR spectroscopy (31P, 1H, 13C) and MALDI-TOF mass spectrometry.
- Quantum-chemical calculations (ab initio, DFT-PBE0/6-311g**) for theoretical estimation of acid strength.
- Analysis of physical state and phase transitions using small-angle X-ray scattering (SAXS).
- Thermal analysis including differential-scanning calorimetry (DSC) and solid-state 13C NMR spectroscopy to study thermal decomposition and polymerization.
Main Results:
- The structure of 2-CEPP was successfully confirmed by spectroscopic and mass spectrometry techniques.
- Quantum-chemical calculations provided theoretical insights into the acid strength of 2-CEPP.
- SAXS analysis indicated that 2-CEPP is amorphous but can crystallize upon heating.
- At 370 °C, 2-CEPP undergoes decarboxylation and polymerization, yielding an insoluble, heat-resistant product.
- DSC and solid-state 13C NMR confirmed the decarboxylation and polymerization reactions.
Conclusions:
- 2-CEPP is a novel cyclotriphosphazene derivative with potential as a precursor for high-performance polymers.
- The thermal decomposition pathway of 2-CEPP involves decarboxylation and polymerization, leading to robust, insoluble materials.
- This study highlights the potential of functionalized cyclotriphosphazenes in developing advanced heat-resistant polymers.
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