Nylon 6/Brazilian clay membranes prepared by phase inversion

Abstract

Microporous membranes were synthesized from a polymer nanocomposite material, intercalated montmorillonite clay/nylon 6, by an immersion-precipitation method in a water bath. This membrane was skinless and was composed of cellular pores and sheaflike crystallites, which were interwoven into a bicontinuous structure. In contrast, pure nylon 6, precipitated under the same conditions, yielded a skinned asymmetric membrane. The X-ray diffraction patterns showed that the nanocomposites and the membranes exhibited exfoliated structures. By differential scanning calorimetry, it was observed that the clay probably acted as a reinforcing filler, increasing the crystallinity degree of the nanocomposites, but it was practically unchanged in the membranes. Through photomicrographs obtained by scanning electron microscopy, it was possible to verify that all the membranes exhibited an asymmetric morphology with a welldefined porous structure and a tight skin with a cellular sublayer.

Modification of a Brazilian smectite clay with different quaternary ammonium salts

“…However, in spite of the large number of works about polymer matrix/clay nanocomposites, only few works relate the use of organoclays of Brazilian origin. 2,[25][26][27][28][29][30][31][32][33][34] Most works use clays from American, Japanese and Chinese origin. 2,9,24 Therefore it is of great interest to study the organofilization of Brazilian clays and their resistance to temperature since to our knowledge, a systematic study on the thermal stability of Brazilian organoclays has never been reported in the literature.…”

Improving the EMI shielding of graphene oxide (GNO)-coated glass-fiber–GNO–MA-grafted polypropylene (PP) composites and nylon 1D–2D nanocomposite foams

“…The Gaussian–Lorentzian function of Origin Pro® is exploited to plot the overlapping curves of the composites. 20–22 GFGMAPP gives rise the peaks at 285.14, 532.4, and 102.47 eV, which are responsible for C1s, O1s, and Si2p, respectively, while GFCFGMAPP engenders corresponding elemental peaks at 285.09, 532.1, and 102.52 eV. Further, GFCFFeGMAPP contains elements such as C1s (258.00 eV), O1s (532.18 eV), Si2p (102.24 eV), Fe (2p 1 at 728.26 eV, and 2p 3 at 710.08 eV), whereas GMAPP only consists of C1s (284.93 eV) and O1s (532.47 eV).…”

“…The Gaussian-Lorentzian function of Origin Pro® is exploited to plot the overlapping curves of the composites. [20][21][22] GFGMAPP gives rise the peaks at 285. 1 and S4 †).…”

“…The 2q peaks at 20.2 and 24.1 indicate the presence of nylon while 26.5 conrms the occurrence of graphite structure, which is from the carbon ber in the nylon composite. 21,22 The Bragg angles at 43.4 and 54.5 conrm the occurrence of concentric MWCNT with sp 2 hybridized carbon. 23 In addition, the 2q peaks at 25-28 and 54.5 indicate the presence of graphene in the composites.…”

Membranes from Nylon 6/Regional Bentonite Clay Nanocomposites

“…The membranes were prepared by spreading this solution on a glass plate and rapidly immerged in a non-solvent bath (distilled water). After the precipitation time, the membranes were removed, washed with distilled water and dried at 60°C for 2 hours [12][13].…”