4 research outputs found
Kinetics of paramagnetic centers decrease at ageing of chemically carbonized derivatives of poly vinylidene fluoride
Relevance of the work. One of the future problems facing modern science is the synthesis and study of the properties of low-dimensional and nanoscale materials based on carbon. Chemical dehydrofluorination of poly vinylidene fluoride (PVDF) allows generating a carbon enriched layer on its surface. Chains of the original polymer may be a promising precursor for synthesis of quasi-1D (carbynoid) structures. Cleavage of fluorine and hydrogen atoms from a carbon skeleton results in formation of unpaired electrons, which contribute in electron spin resonance (ESR) absorption. Deactivation of the formed paramagnetic centers (PMC) can lead to formation of extensive fragments consisted of double and triple carbon-carbon bonds. Besides, one cannot exclude the possibility of other routes of paramagnetic centers deactivation. Studying the kinetics of paramagnetic centers deactivation in chemically dehydrofluorinated poly vinylidene fluoride may give the important information on carbynoid carbon synthesis. Theoretical calculations predict semiconducting type of conductivity for carbynoid carbon, which is of interest for its application in micro- and nanoelectronics. The key point for the further practical usage of a new carbon material is a stability of its physical and chemical properties during long-term storage. The aim of the research is to study in details the deactivation kinetics of paramagnetic centers at long-term storage of chemically dehydrofluorinated poly vinylidene fluoride derivatives; to reveal the atmospheric air effect on paramagnetic centers deactivation. The received data may give ideas on the mechanism of paramagnetic centers deactivation. Research method: ESR spectroscopy.Β Results. The authors have carried out the long-term measurements of the kinetics of ESR absorption reduction of synthesized samples, including those with limited access to air and low pressure. At least four types of paramagnetic centers, differing in deactivation rates, were revealed. The kinetics of deactivation of paramagnetic centers can be described by a set of first-order reactions. It is found that the fastest reactions occur with the atmospheric air
Kinetics of paramagnetic centers decrease at ageing of chemically carbonized derivatives of poly vinylidene fluoride
Relevance of the work. One of the future problems facing modern science is the synthesis and study of the properties of low-dimensional and nanoscale materials based on carbon. Chemical dehydrofluorination of poly vinylidene fluoride (PVDF) allows generating a carbon enriched layer on its surface. Chains of the original polymer may be a promising precursor for synthesis of quasi-1D (carbynoid) structures. Cleavage of fluorine and hydrogen atoms from a carbon skeleton results in formation of unpaired electrons, which contribute in electron spin resonance (ESR) absorption. Deactivation of the formed paramagnetic centers (PMC) can lead to formation of extensive fragments consisted of double and triple carbon-carbon bonds. Besides, one cannot exclude the possibility of other routes of paramagnetic centers deactivation. Studying the kinetics of paramagnetic centers deactivation in chemically dehydrofluorinated poly vinylidene fluoride may give the important information on carbynoid carbon synthesis. Theoretical calculations predict semiconducting type of conductivity for carbynoid carbon, which is of interest for its application in micro- and nanoelectronics. The key point for the further practical usage of a new carbon material is a stability of its physical and chemical properties during long-term storage. The aim of the research is to study in details the deactivation kinetics of paramagnetic centers at long-term storage of chemically dehydrofluorinated poly vinylidene fluoride derivatives; to reveal the atmospheric air effect on paramagnetic centers deactivation. The received data may give ideas on the mechanism of paramagnetic centers deactivation. Research method: ESR spectroscopy.Β Results. The authors have carried out the long-term measurements of the kinetics of ESR absorption reduction of synthesized samples, including those with limited access to air and low pressure. At least four types of paramagnetic centers, differing in deactivation rates, were revealed. The kinetics of deactivation of paramagnetic centers can be described by a set of first-order reactions. It is found that the fastest reactions occur with the atmospheric air
Kinetics of paramagnetic centers decrease at ageing of chemically carbonized derivatives of poly vinylidene fluoride
ΠΠΊΡΡΠ°Π»ΡΠ½ΠΎΡΡΡ ΡΠ°Π±ΠΎΡΡ. ΠΠ΄Π½ΠΎΠΉ ΠΈΠ· ΠΏΠ΅ΡΡΠΏΠ΅ΠΊΡΠΈΠ²Π½ΡΡ
Π·Π°Π΄Π°Ρ, ΡΡΠΎΡΡΠΈΡ
ΠΏΠ΅ΡΠ΅Π΄ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ Π½Π°ΡΠΊΠΎΠΉ, ΡΠ²Π»ΡΠ΅ΡΡΡ ΡΠΈΠ½ΡΠ΅Π· ΠΈ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΠ²ΠΎΠΉΡΡΠ² Π½ΠΈΠ·ΠΊΠΎΡΠ°Π·ΠΌΠ΅ΡΠ½ΡΡ
ΠΈ Π½Π°Π½ΠΎΡΠ°Π·ΠΌΠ΅ΡΠ½ΡΡ
ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ² Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΡΠ³Π»Π΅ΡΠΎΠ΄Π°. Π₯ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΎΠ΅ Π΄Π΅Π³ΠΈΠ΄ΡΠΎΡΡΠΎΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ ΠΏΠΎΠ»ΠΈΠ²ΠΈΠ½ΠΈΠ»ΠΈΠ΄Π΅Π½ΡΡΠΎΡΠΈΠ΄Π° ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΡΠΎΠ·Π΄Π°ΡΡ Π½Π° Π΅Π³ΠΎ ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠΈ ΠΎΠ±ΠΎΠ³Π°ΡΡΠ½Π½ΡΠΉ ΡΠ³Π»Π΅ΡΠΎΠ΄ΠΎΠΌ ΡΠ»ΠΎΠΉ. Π¦Π΅ΠΏΠΈ ΠΈΡΡ
ΠΎΠ΄Π½ΠΎΠ³ΠΎ ΠΏΠΎΠ»ΠΈΠΌΠ΅ΡΠ° ΠΌΠΎΠ³ΡΡ ΠΎΠΊΠ°Π·Π°ΡΡΡΡ ΠΏΠ΅ΡΡΠΏΠ΅ΠΊΡΠΈΠ²Π½ΡΠΌ ΠΏΡΠ΅ΠΊΡΡΡΠΎΡΠΎΠΌ Π΄Π»Ρ ΡΠΈΠ½ΡΠ΅Π·Π° ΠΊΠ²Π°Π·ΠΈΠΎΠ΄Π½ΠΎΠΌΠ΅ΡΠ½ΡΡ
(ΠΊΠ°ΡΠ±ΠΈΠ½ΠΎΠΈΠ΄Π½ΡΡ
) ΡΡΡΡΠΊΡΡΡ. Π ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ΅ ΠΎΡΡΡΠ²Π° ΠΎΡ ΡΠ³Π»Π΅ΡΠΎΠ΄Π½ΠΎΠ³ΠΎ ΡΠΊΠ΅Π»Π΅ΡΠ° Π°ΡΠΎΠΌΠΎΠ² ΡΡΠΎΡΠ° ΠΈ Π²ΠΎΠ΄ΠΎΡΠΎΠ΄Π° ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΠΈΡ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΠ΅ Π½Π΅ΡΠΏΠ°ΡΠ΅Π½Π½ΡΡ
ΡΠ»Π΅ΠΊΡΡΠΎΠ½ΠΎΠ² ΡΠ³Π»Π΅ΡΠΎΠ΄Π°, ΠΊΠΎΡΠΎΡΡΠ΅ Π΄Π°ΡΡ Π²ΠΊΠ»Π°Π΄ Π² ΠΠΠ -ΠΏΠΎΠ³Π»ΠΎΡΠ΅Π½ΠΈΠ΅. ΠΠ΅Π·Π°ΠΊΡΠΈΠ²Π°ΡΠΈΡ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π²ΡΠΈΡ
ΡΡ ΠΏΠ°ΡΠ°ΠΌΠ°Π³Π½ΠΈΡΠ½ΡΡ
ΡΠ΅Π½ΡΡΠΎΠ² ΠΌΠΎΠΆΠ΅Ρ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡΡ ΠΊ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΡ ΠΏΡΠΎΡΡΠΆΠ΅Π½Π½ΡΡ
ΡΡΠ°Π³ΠΌΠ΅Π½ΡΠΎΠ² ΡΠΎΠΏΡΡΠΆΠ΅Π½Π½ΡΡ
Π΄Π²ΠΎΠΉΠ½ΡΡ
ΠΈ ΡΡΠΎΠΉΠ½ΡΡ
ΡΠ³Π»Π΅ΡΠΎΠ΄-ΡΠ³Π»Π΅ΡΠΎΠ΄Π½ΡΡ
ΡΠ²ΡΠ·Π΅ΠΉ. Π’Π°ΠΊΠΆΠ΅ Π½Π΅Π»ΡΠ·Ρ ΠΈΡΠΊΠ»ΡΡΠΈΡΡ ΠΈ Π΄ΡΡΠ³ΠΈΠ΅ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΡ Π΄Π΅Π·Π°ΠΊΡΠΈΠ²Π°ΡΠΈΠΈ ΠΏΠ°ΡΠ°ΠΌΠ°Π³Π½ΠΈΡΠ½ΡΡ
ΡΠ΅Π½ΡΡΠΎΠ². ΠΠ·ΡΡΠ΅Π½ΠΈΠ΅ ΠΊΠΈΠ½Π΅ΡΠΈΠΊΠΈ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ ΠΏΠ°ΡΠ°ΠΌΠ°Π³Π½ΠΈΡΠ½ΡΡ
ΡΠ΅Π½ΡΡΠΎΠ² Π² Ρ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈ Π΄Π΅Π³ΠΈΠ΄ΡΠΎΡΡΠΎΡΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΌ ΠΏΠΎΠ»ΠΈΠ²ΠΈΠ½ΠΈΠ»ΠΈΠ΄Π΅Π½ΡΡΠΎΡΠΈΠ΄Π΅ Π½Π΅ΡΠ΅Ρ Π²Π°ΠΆΠ½ΡΡ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΎ ΠΏΡΠΎΡΠ΅ΡΡΠ΅ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΠΊΠ°ΡΠ±ΠΈΠ½ΠΎΠΏΠΎΠ΄ΠΎΠ±Π½ΠΎΠ³ΠΎ ΡΠ³Π»Π΅ΡΠΎΠ΄Π°. Π’Π΅ΠΎΡΠ΅ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΡΠ°ΡΡΠ΅ΡΡ ΠΏΡΠ΅Π΄ΡΠΊΠ°Π·ΡΠ²Π°ΡΡ ΠΏΠΎΠ»ΡΠΏΡΠΎΠ²ΠΎΠ΄Π½ΠΈΠΊΠΎΠ²ΡΠΉ ΡΠΈΠΏ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠΌΠΎΡΡΠΈ ΠΊΠ°ΡΠ±ΠΈΠ½ΠΎΠΏΠΎΠ΄ΠΎΠ±Π½ΠΎΠ³ΠΎ ΡΠ³Π»Π΅ΡΠΎΠ΄Π°, ΡΡΠΎ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»ΡΠ΅Ρ ΠΈΠ½ΡΠ΅ΡΠ΅Ρ Π΄Π»Ρ Π΅Π³ΠΎ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ Π² ΠΌΠΈΠΊΡΠΎ- ΠΈ Π½Π°Π½ΠΎΡΠ»Π΅ΠΊΡΡΠΎΠ½ΠΈΠΊΠ΅. ΠΠ»ΡΡΠ΅Π²ΡΠΌ ΠΌΠΎΠΌΠ΅Π½ΡΠΎΠΌ Π΄Π»Ρ Π΄Π°Π»ΡΠ½Π΅ΠΉΡΠ΅Π³ΠΎ ΠΏΡΠ°ΠΊΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΈΠ·ΡΡΠ΅Π½ΠΈΠ΅ ΡΡΠ°Π±ΠΈΠ»ΡΠ½ΠΎΡΡΠΈ ΡΠΈΠ·ΠΈΠΊΠΎ-Ρ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠ²ΠΎΠΉΡΡΠ² Π½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠ³Π»Π΅ΡΠΎΠ΄Π½ΠΎΠ³ΠΎ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° ΠΏΡΠΈ Π΅Π³ΠΎ Π΄ΠΎΠ»Π³ΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΌ Ρ
ΡΠ°Π½Π΅Π½ΠΈΠΈ. Π¦Π΅Π»Ρ ΡΠ°Π±ΠΎΡΡ: ΠΏΠΎΠ΄ΡΠΎΠ±Π½ΠΎ ΠΈΠ·ΡΡΠΈΡΡ ΠΊΠΈΠ½Π΅ΡΠΈΠΊΡ Π΄Π΅Π·Π°ΠΊΡΠΈΠ²Π°ΡΠΈΠΈ ΠΏΠ°ΡΠ°ΠΌΠ°Π³Π½ΠΈΡΠ½ΡΡ
ΡΠ΅Π½ΡΡΠΎΠ² ΠΏΡΠΈ Π΄ΠΎΠ»Π³ΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΌ Ρ
ΡΠ°Π½Π΅Π½ΠΈΠΈ Ρ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈ Π΄Π΅Π³ΠΈΠ΄ΡΠΎΡΡΠΎΡΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ΄Π½ΡΡ
ΠΏΠΎΠ»ΠΈΠ²ΠΈΠ½ΠΈΠ»ΠΈΠ΄Π΅Π½ΡΡΠΎΡΠΈΠ΄Π°; Π²ΡΡΡΠ½ΠΈΡΡ Π²Π»ΠΈΡΠ½ΠΈΠ΅ Π°ΡΠΌΠΎΡΡΠ΅ΡΠ½ΠΎΠ³ΠΎ Π²ΠΎΠ·Π΄ΡΡ
Π° Π½Π° ΠΏΡΠΎΡΠ΅ΡΡ Π΄Π΅Π·Π°ΠΊΡΠΈΠ²Π°ΡΠΈΠΈ ΠΏΠ°ΡΠ°ΠΌΠ°Π³Π½ΠΈΡΠ½ΡΡ
ΡΠ΅Π½ΡΡΠΎΠ²; Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΏΠΎΠ»ΡΡΠ΅Π½Π½ΡΡ
Π΄Π°Π½Π½ΡΡ
Π²ΡΠ΄Π²ΠΈΠ½ΡΡΡ ΠΏΡΠ΅Π΄ΠΏΠΎΠ»ΠΎΠΆΠ΅Π½ΠΈΡ ΠΎ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠ°Ρ
Π΄Π΅Π·Π°ΠΊΡΠΈΠ²Π°ΡΠΈΠΈ. ΠΠ΅ΡΠΎΠ΄ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ: ΠΠΠ -ΡΠΏΠ΅ΠΊΡΡΠΎΡΠΊΠΎΠΏΠΈΡ. Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ: ΠΡΠΎΠ²Π΅Π΄Π΅Π½Ρ Π΄ΠΎΠ»Π³ΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΠ΅ ΠΈΠ·ΠΌΠ΅ΡΠ΅Π½ΠΈΡ ΠΊΠΈΠ½Π΅ΡΠΈΠΊΠΈ ΡΠΌΠ΅Π½ΡΡΠ΅Π½ΠΈΡ ΠΠΠ -ΠΏΠΎΠ³Π»ΠΎΡΠ΅Π½ΠΈΡ ΡΠΈΠ½ΡΠ΅Π·ΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
ΠΎΠ±ΡΠ°Π·ΡΠΎΠ², Π² ΡΠΎΠΌ ΡΠΈΡΠ»Π΅, Π² ΡΡΠ»ΠΎΠ²ΠΈΡΡ
ΠΎΠ³ΡΠ°Π½ΠΈΡΠ΅Π½Π½ΠΎΠ³ΠΎ Π΄ΠΎΡΡΡΠΏΠ° Π²ΠΎΠ·Π΄ΡΡ
Π° ΠΈ ΠΏΠΎΠ½ΠΈΠΆΠ΅Π½Π½ΠΎΠ³ΠΎ Π΄Π°Π²Π»Π΅Π½ΠΈΡ. ΠΡΡΠ²Π»Π΅Π½ΠΎ ΠΏΠΎ ΠΌΠ΅Π½ΡΡΠ΅ΠΉ ΠΌΠ΅ΡΠ΅ ΡΠ΅ΡΡΡΠ΅ ΡΠΈΠΏΠ° ΠΏΠ°ΡΠ°ΠΌΠ°Π³Π½ΠΈΡΠ½ΡΡ
ΡΠ΅Π½ΡΡΠΎΠ², ΠΎΡΠ»ΠΈΡΠ°ΡΡΠΈΡ
ΡΡ ΡΠΊΠΎΡΠΎΡΡΡΠΌΠΈ Π΄Π΅Π·Π°ΠΊΡΠΈΠ²Π°ΡΠΈΠΈ. ΠΠΈΠ½Π΅ΡΠΈΠΊΠ° ΠΏΡΠΎΡΠ΅ΡΡΠΎΠ² ΠΈΡΡΠ΅Π·Π½ΠΎΠ²Π΅Π½ΠΈΡ ΠΏΠ°ΡΠ°ΠΌΠ°Π³Π½ΠΈΡΠ½ΡΡ
ΡΠ΅Π½ΡΡΠΎΠ² ΠΌΠΎΠΆΠ΅Ρ Π±ΡΡΡ ΠΎΠΏΠΈΡΠ°Π½Π° ΡΠΎΠ²ΠΎΠΊΡΠΏΠ½ΠΎΡΡΡΡ ΡΠ΅Π°ΠΊΡΠΈΠΉ ΠΏΠ΅ΡΠ²ΠΎΠ³ΠΎ ΠΏΠΎΡΡΠ΄ΠΊΠ°. Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ ΡΠ°ΠΌΡΠ΅ Π±ΡΡΡΡΡΠ΅ ΡΠ΅Π°ΠΊΡΠΈΠΈ ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΡΡ Ρ ΡΡΠ°ΡΡΠΈΠ΅ΠΌ Π°ΡΠΌΠΎΡΡΠ΅ΡΠ½ΠΎΠ³ΠΎ Π²ΠΎΠ·Π΄ΡΡ
Π°.Relevance of the work. One of the future problems facing modern science is the synthesis and study of the properties of low-dimensional and nanoscale materials based on carbon. Chemical dehydrofluorination of poly vinylidene fluoride (PVDF) allows generating a carbon enriched layer on its surface. Chains of the original polymer may be a promising precursor for synthesis of quasi-1D (carbynoid) structures. Cleavage of fluorine and hydrogen atoms from a carbon skeleton results in formation of unpaired electrons, which contribute in electron spin resonance (ESR) absorption. Deactivation of the formed paramagnetic centers (PMC) can lead to formation of extensive fragments consisted of double and triple carbon-carbon bonds. Besides, one cannot exclude the possibility of other routes of paramagnetic centers deactivation. Studying the kinetics of paramagnetic centers deactivation in chemically dehydrofluorinated poly vinylidene fluoride may give the important information on carbynoid carbon synthesis. Theoretical calculations predict semiconducting type of conductivity for carbynoid carbon, which is of interest for its application in micro- and nanoelectronics. The key point for the further practical usage of a new carbon material is a stability of its physical and chemical properties during long-term storage. The aim of the research is to study in details the deactivation kinetics of paramagnetic centers at long-term storage of chemically dehydrofluorinated poly vinylidene fluoride derivatives; to reveal the atmospheric air effect on paramagnetic centers deactivation. The received data may give ideas on the mechanism of paramagnetic centers deactivation. Research method: ESR spectroscopy. Results. The authors have carried out the long-term measurements of the kinetics of ESR absorption reduction of synthesized samples, including those with limited access to air and low pressure. At least four types of paramagnetic centers, differing in deactivation rates, were revealed. The kinetics of deactivation of paramagnetic centers can be described by a set of first-order reactions. It is found that the fastest reactions occur with the atmospheric air