Stability of polyelectrolyte multilayers in oxidizing media: a critical issue for the development of multilayer based membranes for nanofiltration

Long term physical and chemical stability of polyelectrolyte multilayer membranes

“…As the main degradation mechanism of PEM modified membranes by hypochlorite will be caused by an electrophilic attack by the hypochlorite (as is the case in polyamide and poly(arylene sulfone) membranes), (nucleophilic) polycations tend to be more susceptible towards hypochlorite degradation as polyanions. Gregurec et al showed that for different polycations based on ammonium groups, the degree of hypochlorite degradation is dependent on the alkylation degree of the ammonium group [24]. Primary, secondary and tertiary polycations all have a lone electron pair and thus the possibility to donate an electron to the hypochlorite.…”

“…The reactivity of hypochlorite in the presence of different polyelectrolytes was measured by means of UV-vis [24]. For this, 25 ml of a 0.4 g l À 1 hypochlorite solution at pH 8.0 was mixed with either 25 ml of a 0.04 g l À 1 polyelectrolyte solution or with 25 ml water (for the hypochlorite reference).…”

“…Sato et al showed that the degradation rate of multilayers from phenylboronic acid-bearing poly(allylamine) hydrochloride (PBAÀ PAH) and poly(vinyl alcohol) (PVA) was dependent on the H 2 O 2 concentration. The degradation of different polycations by sodium hypochlorite was investigated by Gregurec et al [24], who showed that the stability is determined by the degree of alkylation of the amines.…”

Interpolyelectrolyte complexation of sulfonate-containing aromatic polyamide in aqueous solutions: the influence of the nature of the polybases on the composition of the formed products

“…Они образуются в результате соединения противо-положно заряженных полимерных электролитов или при матричной полимеризации ионных мономеров на противоположно заряженных по-лиионах [1][2][3][4]. Наличие у ИПЭК таких свойств как высокое (но ограниченное) водопоглощение; селективная сорбция ионов и ионообменные свойства; хорошая водопроницаемость, проница-емость для электролитов и водорастворимых микропримесей, непроницаемость для макроком-понентов растворов; антикоагуляционные свой-ства определило мембранную технологию как одну из областей их активного применения [5][6][7][8][9].…”

pH-Dependent Release of Insulin from Layer-by-Layer-Deposited Polyelectrolyte Microcapsules

“…This diversity of methods has led to a variety of materials, including synthetic polymers [9], nanoparticles [10], proteins [11], cells [12], and polysaccharides [13], being used for constructing LbL films. LbL films have been used in sensors [14], separation and purification membranes [15], stimuli-sensitive devices [16,17], and drug delivery systems [18,19]. Hollow microcapsules have also been constructed by coating the surface of microspheres with LbL films followed by dissolution of core material [20][21][22][23][24].…”