- Solubility of HFC32, HFC125, HFC134a, HFC143a, and HFC152a in a pentaerythritol tetrapentanoate ester
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Solubilities of five different hydrofluorocarbons (HFCs) in a pentaerythritol tetrapentanoate ester (95% purity) have been measured at temperatures between 303.15 and 363.15 K and pressures between 0.05 and 1.9 MPa. Henry's constant and the activity coefficient for HFCs at infinite dilution were derived for measurements below 0.26 MPa. The measurements were made with an isochoric method with an uncertainty of less than 2% for Henry's constant and less than 3% at high pressure. Within the investigated temperature range, solubilities for HFCs decrease in the following order: HFC152a > HFC134a > HFC32 > HFC125 > HFC143a. The experimental data have been correlated with a Flory-Huggins model with an extended temperature dependence, which is able to describe the data with a deviation from measured data of less than 2%.
- Wahlstroem, Asa,Vamling, Lennart
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- Retention Indices and Sorption Enthalpies of Pentaerythritol and С2–С8 Acid Esters on Nonpolar Stationary Phases
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Abstract: The retention and sorption enthalpy characteristics of 38 pentaerythritol esters of C2–C8 carboxylic acids of different structures were determined by gas-liquid chromatography on a nonpolar phase in the temperature range 433.2–563.2 K. The molecular structure was shown to affect the temperature dependence of the retention indices of the esters. The average change in the sorption enthalpy of pentaerythritol tetraesters per CH2 group is lower in magnitude than the similar contribution for normal alkanes. The excess mixing enthalpy at 298.2 K was evaluated for four fully substituted pentaerythritol esters.
- Emel’yanov, V. V.,Krasnykh, E. L.,Portnova, S. V.
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p. 2168 - 2176
(2020/10/08)
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- An efficient catalyst COK-15b for the catalytic synthesis of lubricating ester oils
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The new material MOF of (CTA)1/3[Cu46(C9H3O6)24(OH)12] (PW12O40)3·xH2O (COK-15b) was synthesized via a dual-templating approach and exhibited high activity and selectivity for the esterification of pentaerythrotol with fatty acids at stoichiometric ratio to the corresponding pentaerythrotol tetra-esters with up to 98% yields under solvent-free conditions. The COK-15b was characterized by TEM, SEM, TG, BET, TPD and Py-IR. Moreover, the stability of COK-15b was investigated, and it can be reused for 5 running cycles without significant deactivation.
- Wang, Yanan,Ma, Rui,Jiang, Cheng,Lou, Wenjing,Wang, Xiaobo
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- A green way to synthesize lubricating ester oils: The esterification of pentaerythrotol with fatty acids at stoichiometric ratio over [BHSO3MMIm]+[HSO4]?/SiO2
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A green way was provided to produce lubricating ester oils under solvent-free conditions over an ionic liquid catalyst supported with mesoporous silica, which was prepared by using sol-gel method and exhibited high activity and selectivity for the esterification of pentaerythrotol with fatty acid at stoichiometric ratio to the corresponding pentaerythrotol tetra-esters. The catalyst was systematically characterized by TEM, TG/DTA, BET and FT-IR. Moreover, the stability of the catalyst was investigated, and it can be recycled for several times without significant deactivation.
- Wang, Yanan,Lou, Wenjing,Wang, Xiaobo
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- Microwave-promoted synthesis of polyol esters for lubrication oil using a composite catalyst in a solvent-free procedure
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A rapid, highly efficient and green synthetic approach to polyol esters for lubrication oils is proposed. Using sulfuric acid and p-toluene sulfonic acid as a composite catalyst and C5-C9 straight-chain monocarboxylic acids, with pentaerythritol (PE) and dipentaerythritol (di-PE) as starting materials, a series of lubrication oil polyol esters were synthesized in the absence of solvent under microwave irradiation. Compared with the conventional synthetic method, our proposed microwave method exhibits advantages, including higher yields, shorter reaction times and lower reaction temperatures. The viscosity coefficients of the products at 40 °C and their refractive indices at 25 °C were investigated. In addition, the thermal behavior of the starting materials under microwave irradiation was also investigated. The results reveal that the microwave absorbance of n-pentanoic acid is stronger than that of n-hexanoic acid and that of n-heptanoic acid is stronger than that of n-octanoic acid. The microwave absorbance of di-PE is also stronger than that of PE.
- Zhang, Fengxiu,Zhang, Guangxian
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experimental part
p. 178 - 184
(2011/03/23)
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- Polymer containing a polyisobutylene-derived backbone
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Polymers, such as polysiobutylene or ethylene-propylene copolymers, are functionalized by reaction with an activated imine to yield novel polymers.
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- Method of functionalizing polymers
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Polymers, such as polyisobutylene or ethylene-propylene copolymers, are functionalized by reaction with an activated imine to yield novel polymers.
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