• Macromolecular Research
• /
• v.11 no.5
• /
• pp.347-351
• /
• 2003

The hydrophobic ligand-containing hollow polypropylene (PP) membranes were synthesized by the mutual radiation induced graft copolymerization with glycidylmethacrylate (GMA) onto hollow PP membrane followed by the subsequent functionalization with L-phenylalanine. FT-IR, elemental analysis and UV spectroscopy were utilized to characterize copolymer composition, and degree of grafting, functionalization conversion and ${\gamma}$-globulins adsorption. The degree of grafting on the PP surface increased with the reaction time and total dose of E-beam. In the subsquent functionalization, the amount of L-phenylalanine increased with the increase in the degree of grafting and the degree of conversion was about 30%. The ${\gamma}$-globulins adsorption experiments showed that adsorption capacity had a maximum value at pH 8. The ${\gamma}$-globulins adsorption capacity in the basic pH region was higher than in the acidic pH region.

• Analytical Science and Technology
• /
• v.11 no.4
• /
• pp.248-253
• /
• 1998

The adsorption and separation behaviors of alkali, alkaline earth and transition metal ions using a poly-dibenzo-18-crown-6 were investigated in aqueous solution. The adsorption degree(E) and distribution ratio(D) of alkali, alkaline earth metal ions were Li(I)$t_R$) of metal ions were affected by the adsorption degree(E) and distribution ratio(D). This results showed good separation efficiency of K(I), Sr(II), Ag(I) and Pb(II) from the mixed metal solution.

• Analytical Science and Technology
• /
• v.12 no.2
• /
• pp.159-165
• /
• 1999

The adsorption and separation behaviors of transition metal ions using a merrifield resin bound 1,12-diaza-3,4:9,10-dibenzo-5,8-dioxacyclopentadecane (NTOE) and 1,12,15-triaza-3,4:9,10-dibenzo-5,8-dioxacycloheptadecane(NDOE) were investigated in aqueous solution. The orders of adsorption degree(E) and distribution ratio(D) of transition metal ions were Cu(II)$t_R$) of metal ions were affected by adsorption degree(E) and distribution ratio(D). This results showed good separation efficiency of Ag(I) from mixed metal solution.

• Polymer(Korea)
• /
• v.26 no.4
• /
• pp.415-421
• /
• 2002

A sulfonated PP-g-styrene ion-exchange hollow fiber membrane was prepared by pre-irradiation method with E-beam followed by sulfonation reaction. Degree of grafting increased with the increase of styrene monomer concentration and showed the maximum value of 128% at 80% of styrene monomer composition. Sulfonation yield increased with the degree of grafting. At 100% degree of grafting, sulfonation yield showed the maximum value of 13.4%. Ion exchange capacity of sulfonated HPP-g-styrene of 3.42 meq/g was attained, resulting in the remarkable increase of adsorption ability BET analysis proved that the surface area of sulfonated HPP-g-styrene was 62.54 $m^2/g$ and the mean pore size was 25 $\AA$. From the BSA adsorption experiments, the adsorption amount of BSA was increased with sulfonation. At 13.4% sulfonation yield the adsorption amount of BSA was maximum as 3.8 mg/g. Sulfonated HPP-g-styrene was synthesized successfully and suitable for the adsorption and separation of BSA.

• Korean Journal of Materials Research
• /
• v.27 no.3
• /
• pp.127-131
• /
• 2017

Isosteric heat of hydrogen adsorption is one of the most important parameters required to describe solid-state hydrogen storage systems. Typically, it is calculated from adsorption isotherms measured at 77K (liquid N2) and 87K (liquid Ar). This simple calculation, however, results in a high degree of uncertainty due to the small temperature range. Therefore, the original Sievert type setup is upgraded using a heating and cooling device to regulate the wide sample temperature. This upgraded setup allows a wide temperature range for isotherms (77K ~ 117K) providing a minimized uncertainty (error) of measurement for adsorption enthalpy calculation and yielding reliable results. To this end, we measure the isosteric heats of hydrogen adsorption of two prototypical samples: activated carbon and metal-organic frameworks (e.g. MIL-53), and compared the small temperature range (77~87K) to the wide one (77K ~ 117K).

• Polymer(Korea)
• /
• v.25 no.1
• /
• pp.49-55
• /
• 2001

The bi-functional ion exchangers, SAPP-g-(AN/St) were synthesized with mixed vinyl monomers(acrylonitrile and styrene) onto PP fabric by the pre-irradiation grafting with E-beam and its subsequent amidoximination and sulfonation. The degree of grafting of PP-g-(AN/St) was increased with decreasing acrylonitrile composition in the mixed monomers. The water uptake of copolymers increased with decreasing in the amidoxime ratio in the copolymers and increased by sulfonation, but decreased by amidoximation. The $UO_2^{2+}$ adsorption capacity of SPP-g-St, APP-g-AN, and SAPP-g-(AN/St) were 12.4, 34.0, and 38.0 mg/g, respectively and the optimum adsorption time is about 50 hrs. As a result of uranium adsorption, the synthesized ion exchanger, which we obtained have also good affinity toward the adsorption or chelating with $UO_2^{2+}$ ions.

• Polymer(Korea)
• /
• v.24 no.6
• /
• pp.763-769
• /
• 2000

The multifunctional cation exchangers, sulfonated polypropylene-g-(acrylic acid/styrene) [PP-g-(AAc/Sty)] were synthesized by the irradiational grafting of AAc and Sty onto PP staple fabric with electron beam accelerator and its subsequent sulfonation. The highest degree of grafting obtained was 190% at a monomer mixture of 30 vol% AAc: 70 vol% Sty and a solvent mixture of 30 vol% water : 70 vol% methanol and the degree of grafting decreased with an increase of the AAc content in the monomer mixture at constant solvent content. Maximum ion exchange capacity of the copolymer was 4.6 meq/g. The Li$^{+}$ adsorption ability of the copolymer synthesized in the study was the best among PP-g- AAc, sulfonated PP-g-Sty, and sulfonated PP-g-(AAc/Sty).).

• Analytical Science and Technology
• /
• v.8 no.3
• /
• pp.299-304
• /
• 1995

The adsorption behaviors of Ba(II), Cr(II), Fe(II) and Cu(II) on the N, N'-bispalmtoyl 1, 12-diaza-3, 4:9, 10-dibenzo-5, 8-cyclopentadecane (hexadecyl $NtnOenH_4$)-octadecylsilanized silicas(ODS) were investigated with water as the mobile phase. Binding constants for metal ions were measured in aqueous solution. The order of binding constants(K) and the degree of sorption(E) were Ba(II)$NtnOenH_4$-octadecyisiianized silicas(ODS) increased with concentration of metal ions, and the degree of adsorption was found to be affected by the cation-chelation mechanism. The experimental results showed good efficiency for separation of Cu(II) from mixtures of Ba(II), Cr(II), Fe(II) and Cu(II) in aqueous solution.

• Polymer(Korea)
• /
• v.26 no.2
• /
• pp.160-167
• /
• 2002

We synthesized HPP-g-GMA copolymer using pre-irradiation method by E-beam and aminated HPP-g-GMA using amination reaction. Degree of grafting increased with increasing GMA monomer concentration and showed the maximum value of 130% at 1.46 M of GMA. The degree of amination increased with increasing the degree of grafting. When the degree of grafting was 100%, degree of amination showed the maximum value of 37.4%. The ion exchange capacity of aminated HPP-g-GMA was about 3.78 meq/g, and it showed remarkable adsorption ability of hollow fiber ion exchanger. Through the BET analysis, the surface area of aminated HPP-g-GMA was 54.83 $\m^2/g$ and the mean pore size was $26\AA$. These showed the decrease of surface area and the slight increase of the mean pore size. SEM results show that the thickness of fiber increased after the step of reaction and there pore blocking phenomena was not observed. The aminated HPP-g-GMA was synthesized successfully and found to be suitable for the adsorption and separation of anion.

• Polymer(Korea)
• /
• v.25 no.4
• /
• pp.451-459
• /
• 2001

Fabric ion-exchanger, aminated PP-g-styrene was synthesized with styrene monomer onto PP staple fiber by pre-irradiational grafting with E-beam and subsequent chloromethylation and amination. Degree of grafting was increased with increasing the styrene monomer concentration and the highest degree of grafting was obtained 118% at a monomer concentration of 80% styrene. Optimum condition of Mohr's salt and sulphuric acid were 1.0 ${\times}\;10^{-3}$ M and 0.1 M. Amount of amination was increased with increasing degree of grafting. Swelling ratio of aminated PP-g styrene was higher than that of trunk polymer. Ion-exchange capacity was 6.7 meq/g, which was three times greater than commercial ion-exchanger. Optimum condition of baron ion adsorption was pH 4 and amount of adsorption were increased with increasing the amount of amination.