6 research outputs found
Enzymatic Oligomerization of <i>p</i>‑Methoxyphenol and Phenylamine Providing Poly(<i>p</i>‑methoxyphenol-phenylamine) with Improved Antioxidant Performance in Ester Oils
Poly(<i>p</i>-methoxyphenol-phenylamine), denoted as
P(MOP-PA), was synthesized via the enzymatic oligomerization of <i>p</i>-methoxyphenol and phenylamine monomers in the presence
of horseradish. The structure of the as-synthesized product was confirmed
by Fourier transform infrared spectrometry, time-of-flight mass spectrometry,
and elemental analysis, and the oligomerization process was studied
by high-performance liquid chromatography. Moreover, the antioxidation
behavior of P(MOP-PA) as an antioxidant in several ester oils was
evaluated by rotary oxygen bomb test and pressurized differential
scanning calorimetry, and its antioxidant mechanism was discussed.
It was found that, as the antioxidant in various base oils, P(MOP-PA)
exhibits excellent antioxidation ability at elevated temperatures
of 150 and 210 °C. In addition, P(MOP-PA) has an antioxidant
ability that is better than that of poly(<i>p</i>-methoxyphenol),
and it exhibits an antioxidation ability in synthetic ester oil, such
as di-iso-octyl sebacate, that is much better than that of several
commonly used commercial hindered phenolic antioxidants
Synthesis of 1,3,5-Tris(phenylamino) Benzene Derivatives and Experimental and Theoretical Investigations of Their Antioxidation Mechanism
1,3,5-Tris(phenylamino) benzene and
a series of its substitution
derivatives were synthesized. The structure of the as-synthesized
products was confirmed by nuclear magnetic resonance spectroscopy
and high resolution mass spectra. Moreover, the antioxidation behavior
of 1,3,5-tris(phenylamino) benzene and its substitution derivatives
as antioxidants in several ester oils was evaluated by a rotary oxygen
bomb test and pressurized differential scanning calorimetry, while
theoretical calculations were conducted to examine their antioxidation
mechanism. It was found that 1,3,5-tris(phenylamino) benzene exhibits
better antioxidation ability at elevated temperature (150 and 210
°C) than commonly used commercial antioxidant diphenylamine.
In the meantime, the substitution groups exhibit significant effects
on the antioxidation behavior of 1,3,5-tris(phenylamino) benzene and
its derivatives. This is because the substituents result in changes
in the molecular structure and electronic effect of the as-synthesized
products, thereby causing s change in their antioxidation behavior
Polyurea–Cellulose Composite Aerogel Fibers with Superior Strength, Hydrophobicity, and Thermal Insulation via a Secondary Molding Strategy
Aerogel materials, considered as the “miracle
material that
can change the world in the 21st century”, owe their transformative
potential to their high specific surface area, porosity, and low density.
In comparison to commercially available aerogel felt, aerogel particles,
and aerogel powder, aerogel fibers not only possess the inherent advantages
of aerogel materials but also exhibit exceptional flexibility and
design versatility. Therefore, aerogel fibers are expected to be processed
into high-performance textiles and smart wearable fabrics to further
expand the application field of aerogel materials. However, the aerogel
fibers suffer from poor mechanical properties and intricate, time-consuming
preparation processes. Herein, a simple and efficient method for crafting
polyurea–cellulose composite aerogel fibers (CAFs) with superior
mechanical properties is presented. The dried bacterial cellulose
(BC) matrix was immersed in a polyurea sol, and the aerogel fibers
were prepared via secondary molding, followed by CO2 supercritical
drying. In a representative case, the CAFs obtained via secondary
molding demonstrate outstanding hydrophobicity with a contact angle
of 126°, along with remarkable flexibility. Significantly, the
CAFs exhibit excellent mechanical properties, including a tensile
strength of 6.4 MPa. Moreover, the CAFs demonstrate superior thermal
insulation capabilities, withstanding temperatures ranging from 180
to −40 °C. In conclusion, with the successful fabrication
of polyurea–cellulose CAFs, this study introduces a magic approach
for producing aerogel fibers endowed with exceptional mechanical properties
and thermal insulation. This advancement contributes to the development
and application of aerogel materials in various fields
Polyurea–Cellulose Composite Aerogel Fibers with Superior Strength, Hydrophobicity, and Thermal Insulation via a Secondary Molding Strategy
Aerogel materials, considered as the “miracle
material that
can change the world in the 21st century”, owe their transformative
potential to their high specific surface area, porosity, and low density.
In comparison to commercially available aerogel felt, aerogel particles,
and aerogel powder, aerogel fibers not only possess the inherent advantages
of aerogel materials but also exhibit exceptional flexibility and
design versatility. Therefore, aerogel fibers are expected to be processed
into high-performance textiles and smart wearable fabrics to further
expand the application field of aerogel materials. However, the aerogel
fibers suffer from poor mechanical properties and intricate, time-consuming
preparation processes. Herein, a simple and efficient method for crafting
polyurea–cellulose composite aerogel fibers (CAFs) with superior
mechanical properties is presented. The dried bacterial cellulose
(BC) matrix was immersed in a polyurea sol, and the aerogel fibers
were prepared via secondary molding, followed by CO2 supercritical
drying. In a representative case, the CAFs obtained via secondary
molding demonstrate outstanding hydrophobicity with a contact angle
of 126°, along with remarkable flexibility. Significantly, the
CAFs exhibit excellent mechanical properties, including a tensile
strength of 6.4 MPa. Moreover, the CAFs demonstrate superior thermal
insulation capabilities, withstanding temperatures ranging from 180
to −40 °C. In conclusion, with the successful fabrication
of polyurea–cellulose CAFs, this study introduces a magic approach
for producing aerogel fibers endowed with exceptional mechanical properties
and thermal insulation. This advancement contributes to the development
and application of aerogel materials in various fields
Polyurea–Cellulose Composite Aerogel Fibers with Superior Strength, Hydrophobicity, and Thermal Insulation via a Secondary Molding Strategy
Aerogel materials, considered as the “miracle
material that
can change the world in the 21st century”, owe their transformative
potential to their high specific surface area, porosity, and low density.
In comparison to commercially available aerogel felt, aerogel particles,
and aerogel powder, aerogel fibers not only possess the inherent advantages
of aerogel materials but also exhibit exceptional flexibility and
design versatility. Therefore, aerogel fibers are expected to be processed
into high-performance textiles and smart wearable fabrics to further
expand the application field of aerogel materials. However, the aerogel
fibers suffer from poor mechanical properties and intricate, time-consuming
preparation processes. Herein, a simple and efficient method for crafting
polyurea–cellulose composite aerogel fibers (CAFs) with superior
mechanical properties is presented. The dried bacterial cellulose
(BC) matrix was immersed in a polyurea sol, and the aerogel fibers
were prepared via secondary molding, followed by CO2 supercritical
drying. In a representative case, the CAFs obtained via secondary
molding demonstrate outstanding hydrophobicity with a contact angle
of 126°, along with remarkable flexibility. Significantly, the
CAFs exhibit excellent mechanical properties, including a tensile
strength of 6.4 MPa. Moreover, the CAFs demonstrate superior thermal
insulation capabilities, withstanding temperatures ranging from 180
to −40 °C. In conclusion, with the successful fabrication
of polyurea–cellulose CAFs, this study introduces a magic approach
for producing aerogel fibers endowed with exceptional mechanical properties
and thermal insulation. This advancement contributes to the development
and application of aerogel materials in various fields
Polyurea–Cellulose Composite Aerogel Fibers with Superior Strength, Hydrophobicity, and Thermal Insulation via a Secondary Molding Strategy
Aerogel materials, considered as the “miracle
material that
can change the world in the 21st century”, owe their transformative
potential to their high specific surface area, porosity, and low density.
In comparison to commercially available aerogel felt, aerogel particles,
and aerogel powder, aerogel fibers not only possess the inherent advantages
of aerogel materials but also exhibit exceptional flexibility and
design versatility. Therefore, aerogel fibers are expected to be processed
into high-performance textiles and smart wearable fabrics to further
expand the application field of aerogel materials. However, the aerogel
fibers suffer from poor mechanical properties and intricate, time-consuming
preparation processes. Herein, a simple and efficient method for crafting
polyurea–cellulose composite aerogel fibers (CAFs) with superior
mechanical properties is presented. The dried bacterial cellulose
(BC) matrix was immersed in a polyurea sol, and the aerogel fibers
were prepared via secondary molding, followed by CO2 supercritical
drying. In a representative case, the CAFs obtained via secondary
molding demonstrate outstanding hydrophobicity with a contact angle
of 126°, along with remarkable flexibility. Significantly, the
CAFs exhibit excellent mechanical properties, including a tensile
strength of 6.4 MPa. Moreover, the CAFs demonstrate superior thermal
insulation capabilities, withstanding temperatures ranging from 180
to −40 °C. In conclusion, with the successful fabrication
of polyurea–cellulose CAFs, this study introduces a magic approach
for producing aerogel fibers endowed with exceptional mechanical properties
and thermal insulation. This advancement contributes to the development
and application of aerogel materials in various fields