Effect of acid acceptor on synthesis of new copolyamide with piperazine moiety

Konagaya, Shigeji; Watanabe, Osamu; Kaji, Atsushi

doi:10.1002/(sici)1097-4628(20000509)76:6<921::aid-app19>3.0.co;2-y

Cited by 4 publications

(8 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To further improve water permeability, the introduction of hydrophilic groups into the polymer backbone is one of the effective methods. 14,16,[28][29][30] For example, thick single membranes (20-40 lm) based on disulfonated poly(arylene ether sulfone) 16,28,29 and sulfonated poly(arylene ether) 29 were previously studied and these membranes showed the improvement of water permeability according to the ratio of introducing hydrophilic groups into the polymer chains. These previous observations prompted us to study the effect of the hydrophilic group on water transport properties of PBI membranes.…”

Section: Effect Of the Hydrophilic Group And Crosslinked Structure Onmentioning

confidence: 99%

“…However, the main obstacle to using the crosslinked PA thin-film composite membrane is its chlorine instability, which leads to an irreversible performance loss over time. 3,14,15 Chlorine is the most widely used oxidizing biocide in water treatment because of its low price and high effectiveness. Thus, when the crosslinked PA thin-film composite membrane is used for the desalination process, it requires expensive dechlorination and rechlorination treatment steps.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of primary structure on permselectivity of ultrathin semipermeable polybenzimidazole membrane

Aiba

Tokuyama

Matsumoto

et al. 2014

J of Applied Polymer Sci

View full text Add to dashboard Cite

A series of polybenzimidazoles (PBIs) with different main chains and sulfonated PBI were successfully synthesized from the corresponding dicarboxylic acids and 3,3'-diaminobenzidine for the formation of ultrathin, single-component, and semipermeable membranes. Furthermore, the covalently crosslinked PBI membrane was prepared by the reaction of sulfonated PBI with divinyl sulfone. Their water transport properties were evaluated under a reverse osmosis mode and compared with the primary structure based on the water permeability (A) and salt permeability (B) values normalized by the membrane thickness. It was found that the A and B values of the PBIs were improved with increasing the weight ratio of the imidazole rings per repeating unit, the introduction of sulfonate group as the hydrophilic group to the PBI was an effective way to enhance the A value, and the crosslinked structure enhanced the salt rejection rate (R) value while maintaining the water flux.

show abstract

Section: Effect Of the Hydrophilic Group And Crosslinked Structure Onmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effect of primary structure on permselectivity of ultrathin semipermeable polybenzimidazole membrane

Aiba

Tokuyama

Matsumoto

et al. 2014

J of Applied Polymer Sci

View full text Add to dashboard Cite

show abstract

“…Reduced viscosity (sp/C) of 4T-PIP(30) was measured at a concentration of 0.5 g/dL in NMP at 30°C using a suspended type Ubbelohde viscometer. NMR spectrum of 4T-PIP(30) was measured at 50°C with a Varian XL-300 (300 MHz 1 H-NMR spectrum) in d 6 -dimethylsulfoxide and its microstructure was identified according to previous reports 17 and the literature. 18 -22 Viscoelasticity of a dense film with the thickness of 10 m was measured at 35 Hz in an N 2 atmosphere and in pure water with a heating rate of 2°C/min using Rheology's DVE-V4 FT-Rheospectror with a water tank.…”

Section: Characterizationmentioning

confidence: 99%

“…The amide bond of 4T-PIP(30) copolyamide is less attacked by proton (H ϩ ) because the bond is inactivated by the electron withdrawing group (-SO 2 -), as shown in Figure 1. 26,27…”

Section: Ro Performancementioning

confidence: 99%

New chlorine‐resistant polyamide reverse osmosis membrane with hollow fiber configuration

Konagaya¹,

Nita²,

Matsui³

et al. 2001

J. Appl. Polym. Sci.

Self Cite

View full text Add to dashboard Cite

New asymmetric hollow fiber reverse osmosis (RO) membrane was developed from a new chlorine-resistant copolyamide [4T-PIP(30)] with a piperazine moiety by a conventional phase-separation method. The new 4T-PIP(30) hollow fiber membrane has the same low-pressure RO performance as cellulose triacetate hollow fiber membrane (FR ϭ 205 L/m 2 day, Rj ϭ 99.6%) and superior chlorine resistance as well as pH resistance to conventional aramid RO membranes. Structural analysis and viscoelastic study revealed that the new hollow fiber consisted of a top skin, dense layer, and microporous layer, and that it began to decrease its elasticity at 80°C in water, which is possibly related to its good and stable RO performance around room temperature. Several kinds of RO modules were made from the new hollow fiber membranes, for which RO performances were stable for 2 years in chlorinated feed water desalination (the free residual chlorine ranged from 0.l to 1.1 mg/L).

show abstract

“…Such sulfonated copolyamides could be used as ion exchange membranes in fuel cells. [11][12][13] In textile applications, polyamide-bearing sulfonate groups have been obtained via copolymerization of adipic Additional Supporting Information may be found in the online version of this article. acid and lithium salt of 5-sulfoisophthalic acid (LiSIPA) with HMD in order to improve dyeing process and stain resistance.…”

mentioning

confidence: 99%

Synthesis of copolyamides based on PA 66 bearing lithium sulfonate groups and having unique thermal properties

Cammage

Spitz

Boisson

et al. 2011

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

Copolyamides of PA 66/6 lithium 5‐sulfoisophthalic acid (LiSIPA) containing up to 40 mol % of LiSIPA were prepared in a 1L‐pilot reactor operating at high pressures and high temperatures. Interestingly, the presence of lithium sulfonate moieties highly impacted the glass transition temperature of the polyamide. The Tg increased from 59 °C for PA 66 to 155 °C for a copolymer containing about 40 mol % of LiSIPA. 1,3‐Dihexylbenzenedicarboxamide and lithium p‐toluenesulfonate were synthesized as model compounds to investigate the interaction of lithium sulfonate moieties and amide functions. Infrared spectroscopy using ATR technology performed on mixture of both compounds showed that the carbonyl group of amide functions interacts with the lithium cation of lithium sulfonate moieties. Similar SO and CO adsorption bands were observed in copolyamides PA 66/6LiSIPA and in mixture of model compounds, which strongly suggest the formation in the copolyamides of physical cross‐linking points centered on lithium cations coordinated by carbonyl groups of amide functions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

show abstract

Effect of acid acceptor on synthesis of new copolyamide with piperazine moiety

Cited by 4 publications

References 9 publications

Effect of primary structure on permselectivity of ultrathin semipermeable polybenzimidazole membrane

Effect of primary structure on permselectivity of ultrathin semipermeable polybenzimidazole membrane

New chlorine‐resistant polyamide reverse osmosis membrane with hollow fiber configuration

Synthesis of copolyamides based on PA 66 bearing lithium sulfonate groups and having unique thermal properties

Contact Info

Product

Resources

About