• Membrane Journal
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• v.30 no.6
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• pp.409-419
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• 2020

In this study, PEBAX/ZIF-8 and PEBAX/amineZIF-8 composite membranes were prepared according to the content of zeolitic imidazolate framework-8 (ZIF-8), amine-modified ZIF-8 (amineZIF-8), the gas permeability properties of N2 and CO2 were investigated for each composite membrane. In the case of the PEBAX/ZIF-8 composite membrane, the permeability of N2 and CO2 increased as the ZIF-8 content increased, and in the case of the PEBAX/amineZIF-8 composite membrane, the permeability of N2 and CO2 increased up to 20 wt% of amineZIF-8, but decreased at the higher content. CO2/N2 ideal selectivity increased up to 20 wt% of ZIF-8 and amineZIF-8 contents in both PEBAX/ZIF-8 and PEBAX/ amineZIF-8 composite membranes, and then decreased thereafter, in the case of PEBAX/amineZIF-8 composite membrane was less decreased. The reason for the highest CO2/N2 ideal selectivity at 20 wt% of amineZIF-8 is that amine modification improved the compatibility between PEBAX and amineZIF-8, and thus amineZIF-8 was evenly dispersed in PEBAX, resulting in the greatest effect of the porous ZIF-8 with a 3.4 Å pore size and the amine with affinity for CO2.

• Analytical Science and Technology
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• v.18 no.3
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• pp.216-223
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• 2005

In this study, several kinds of volatile amines in ambiant air were collected and their concentrations were expected from the calibration curves prepared by standard solutions of 7 amines by the official measuring method prescribed in Japanese Offensive Odor Law. The obtained calibration curves showed a good linearity and the detection limit of trimethyl amine was found to be about 0.033 ppb (0.040 ng) in case of 50 liters air. It means that trimethyl amine could be detected with the concentration of lower than its permitting level at the border line of companies. As typical examples of measuring amines in air, results of investigation of two sewage works and one rendering plant around the capital area indicated that 4 kinds of amines, i.e. methyl amine, dimethyl amine, trimethyl amine and isopropyl amine were detectable and concentrations of trimethyl amine at the primary sedimentation pond and sludge dewatering building of the sewage plant A showed 9.07 ppb and 7.79 ppb respectively, being over the concentration of odor strength 2.5, And the aeration tank, excrement input facility and indoor of maintenance room of excrement process building in the sewage plant B showed 70.0 ppb of dimethyl amine and 2.44 ppb of trimethyl amine.

• Applied Chemistry for Engineering
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• v.31 no.6
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• pp.679-687
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• 2020

In this study, poly(ether-block-amide) (PEBAX)/zeolitic imidazolate framework-8 (ZIF-8)-polyetherimide (PEI), and PEBAX/amine-modified ZIF-8 (amineZIF-8)-PEI composite membranes were prepared by varying the contents of ZIF-8 and amineZIF-8. Also the gas permeability properties of N2 and CO2 were investigated for each composite membrane. The N2 and CO2 permeability of the PEBAX/ZIF-8-PEI composite membrane increased as the ZIF-8 content increased, while the CO2/N2 selectivity gradually decreased. In the case of the PEBAX/amineZIF-8-PEI composite membrane, the permeability of N2 decreased slightly, and CO2 increased till amineZIF-8 amount was 0.5 wt% and then decreased when the content increased further. The CO2/N2 selectivity was the highest with a value of 78.3 at 0.5 wt% of amineZIF-8. because the amine modification in the amineZIF-8 improves the compatibility between PEBAX and amineZIF-8, It seems that amineZIF-8 was evenly dispersed in PEBAX, which could be greatly influenced by the porousity of ZIF-8 and also the affinity of amine toward CO2.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3377-3381
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• 2011

In this work, the amine grafting treated activated carbons were studied for carbon dioxide adsorbent. The surfaces of activated carbon were functionalized by 3-chloropropyltrimethoxysilane, which was subsequently grafted with amine compounds tris-(2-aminoethyl)amine and tri-ethylenetetramine and subjected to comparison. The surface functional groups of the amine grafted activated carbons were characterized using XPS. The textural properties of the amine grafted activated carbons were analyzed by $N_2$/77 K isotherms. Carbon dioxide adsorption behaviors of the amine grafted activated carbons were examined via the amounts of carbon dioxide adsorption at 298 K and 1.0 atm. From the results, tris-(2-aminoethyl)amine grafted activated carbons showed 43.8 $cm^3$/g of carbon dioxide adsorption while non-treated activated carbons and triethylenetetramine grafted activated carbons showed less carbon dioxide adsorption. These results were thought to be due to the presence of isolated amine groups in the amine compounds. Tris-(2-aminoethyl)amine grafted activated carbons have basic features that result in the enhancement of adsorption capacity of the carbon dioxide molecules, which have an acidic feature.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.619-626
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• 2023

Primary and secondary amine-based sorbents were synthesized to investigate the operation capacity for the carbon dioxide separation TSA process. (3-Aminopropyl) triethoxysilane was used as a primary amine precursor as a crosslinking agent to synthesize a secondary amine precursor in which amine groups were crosslinked with a crosslinking agent. Carbon dioxide absorbed by primary amines is completely separated above 170 ℃. The working capacity of the primary amine absorbent was less than 2% when regenerated at 130℃. The secondary amine absorbent has a higher carbon dioxide separation capacity at a lower regeneration temperature than the primary amine absorbent. The secondary amine absorbent could predict process operation performance of about 6.5% with 2% carbon dioxide absorption and 100% carbon dioxide regeneration conditions. Therefore, it was found that the working capacity of the secondary amine absorbent was higher than that of the primary amine.

• Journal of dental hygiene science
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• v.8 no.3
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• pp.109-115
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• 2008

Two t-amines, N,N-dimethylaniline (MA), N,N-dimethyl-p-toluidine (MPT), were investigated as new visible light amine initiators for a dental resin composite of UDMA in order to improve photopolymerization effect. Three t-amines mixed with three photosensitizers, camphorquinone(CQ), 1-phenyl-1,2-propane dione(PD) and diacetyl (DA), respectively. And then this mixtures are added to resin monomer, UDMA. Photopolymerization efficiency of UDMA was studied through the use of FT-IR absorption spectroscopy. The photopolymerization effect of amine initiators were compared with that of 4-(dimethylamino)ethyl methacrylate (AEM), the most widely used photoinitiator. The photopolymerization efficiency of UDMA containing the amine initiator increased with irradiation time. The relative polymerization efficiency containing the CQ photosensitizer increase was in the order: AEM < MPT < MA. And the relative polymerization efficiency containing the PD photosensitizer increase was in the order: MPT < AEM < MA. This result shows that MA is most efficient amine initiator with CQ and PD.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.135-140
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• 2012

In this study, the heats of absorption of $CO_2$ with aqueous solutions of primary, secondary and tertiary amine aqueous solutions were measured in the commercial reaction calorimeter SIMULAR (HEL, UK). The heats of absorption of 30 wt% amine aqueous solutions of MEA (monoethanolamine, primary amine), EAE(2-(ethylamino)ethanol, secondary amine), and MDEA (methyldiethanolamine, tertiary amine) were measured as function of the $CO_2$ loading ratio at $40^{\circ}C$, in each case. In addition, the heats of absorption of sterically-hindered amine aqueous solutions of AMP(2-amino-2-methyl-1-propanol, primary amine), DEA(diethanolamine, secondary amine) and TEA(triethanolamine, tertiary amine) were measured to observe the steric hindrance effect. The heat of absorption is high in the following order regardless of the steric hindrance: primary amine > secondary amine > tertiary amine. The heats of absorption of amines having sterically-hindered substituents surrounding nitrogen atoms are relatively low compare to that of sterically-free amines, although the difference is very small.

• Carbon letters
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• v.10 no.3
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• pp.221-224
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• 2009

In this work, the $CO_2$ adsorption behaviors of amine functionalized activated carbons (ACs) were investigated. The surface of ACs was modified with urea, melamine, diethylenetriamine (DETA), pentaethylenehexamine (PEHA), polyethylenimine (PEI), and 3-aminopropyl-triethoxysilane (ATPS). The various surface properties of amine functionalized ACs were characterized by Boehm's method, nitrogen full isotherms, XPS, and TGA analyses. The active ingredients impregnated on the ACs show significant influence on the adsorption for $CO_2$ and its volumes adsorbed on amine functionalized ACs are larger than that on the pristine ACs, which is due to the grafted amine groups of the AC surfaces.

• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1149-1152
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• 1999

1H NMR spectrum of a DMF-d7 solution containing 4-aminopyrimidine and [SiW11CoIIO39]6- (SiW11Co) shows separate peaks from two linkage isomers, a and b, in which N(1) and N(3) of the pyrimidine ring are coordinated to SiW11Co, respectively. The signal from the amine group in the isomer a exhibits temperature dependence that is characteristic of a two-site exchange problem. Rates of internal rotation of the amine group were determined by simulating the NMR spectra at 5-35℃. The amine group of free 4-aminopyrimidine also shows temperature-dependent spectra at lower temperatures; rates of internal rotation at (-25)-25℃ were determined. The internal rotation of the amine group in the complex is much slower than that for free 4-aminopyrimidine, indicating that π-character of the C-N bond increases on coordination to SiW11Co. The amine group in the isomer b does not show such behavior. It is probable that hydrogen bonding between N-H and a bridging oxygen atom of SiW11Co prevents it from rotating at low temperatures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.164-165
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• 2021

To prepare the good-adherent and weather-resistant acrylic resin coatings, acrylic resin was prepared by a radical polymerization. Glass transition temperature(Tg) of the acrylic copolymer was fixed at 30℃ and the contents of tertiary amine monomer(DMAEMA) was varied to be 5, 10, 15, 20 wt% respectively. γ-Glycidoxypropyltrimethoxysilane(GPTMS) containing epoxy group was used for curing agents and di-n-butyltindilaurate(DBTDL) was used for drying accelerator. The equivalent ratio of amine to epoxy was 1:1. The prepared coatings exhibited excellent adhesion to various substrates, and various physical properties of the coatings were satisfactory. The gloss retention and color difference were improved at low tertiary amine concentration. The coatings containing 10wt% tertiary amine concentration have especially good weather resistant properties.