scispace - formally typeset
Topic

Montmorillonite

About: Montmorillonite is a(n) research topic. Over the lifetime, 13981 publication(s) have been published within this topic receiving 368796 citation(s).

...read more

Papers
More filters

Journal ArticleDOI
Yoshitsugu Kojima1, Arimitsu Usuki1, Masaya Kawasumi1, Akane Okada1  +3 moreInstitutions (1)
Abstract: Various nylon 6-clay hybrids, such as molecular composites of nylon 6 and silicate layers of montmorillonite and saponite, NCH's and NCHP's, respectively, have been synthesized. To estimate the mechanical properties of these hybrids, tensile, flexural, impact, and heat distortion tests were carried out. NCH was found superior in strength and modulus and comparable in impact strength to nylon 6. The heat distortion temperature (HDT) of NCH (montmorillonite: 4.7 wt. %) was 152 °C, which was 87 °C higher than that of nylon 6. In NCHP, saponite had a smaller effect on the increase of these mechanical properties. The modulus and HDT of NCH and NCHP increased with an increase in the amount of clay minerals. It was found that these properties were well described by the contribution of the constrained region calculated from the storage and loss modulus at the glass transition temperature. According to the mixing law on elastic modulus, the following expression was obtained between the modulus E at 120 °C and the fraction of the constrained region C, En = Ecn = C, where the values of n and Ec (modulus of the constrained region) were 0.685 and 1.02 GPa, respectively.

...read more

2,431 citations


Journal ArticleDOI
Arimitsu Usuki1, Yoshitsugu Kojima1, Masaya Kawasumi1, Akane Okada1  +3 moreInstitutions (1)
Abstract: It was found that montmorillonite cation exchanged for 12-aminolauric acid (12-montmorillonite) was swollen by ∊-caprolactam to form a new intercalated compound. Caprolactam was polymerized in the interlayer of montmorillonite, a layer silicate, yielding a nylon 6-clay hybrid (NCH). The silicate layers of montmorillonite were uniformly dispersed in nylon 6. The carboxyl end groups of 12-aminolauric acid in 12-montmorillonite initiated polymerization of ∊-caprolactam, and as 12-montmorillonite content became larger, the molecular weight of nylon was reduced. From the result of end-group analysis, carboxyl end groups were more than amino end groups. The difference between the carboxyl and the amino end groups was attributed to ammonium cations (-NH3+) of nylon molecules, because the difference agreed with the anion site concentration of the montmorillonite in NCH. It is suggested that the ammonium cations in nylon 6 interact with the anions in montmorillonite.

...read more

2,095 citations


Journal ArticleDOI
Kazuhisa Yano1, Arimitsu Usuki1, Akane Okada1, Toshio Kurauchi1  +1 moreInstitutions (1)
Abstract: A polyimide hybrid with montmorillonite clay mineral has been synthesized from a dimethylacetamide (DMAC) solution of poly(amic acid) and a DMAC dispersion of montmorillonite intercalated with an ammonium salt of dodecylamine. Montmorillonite consists of stacked silicate sheets about 2000 A in length, 10 A in thickness. In this hybrid, montmorillonite is dispersed homogeneously into the polyimide matrix and oriented parallel to the film surface. Thanks to this special structure, this hybrid showed excellent gas barrier properties. Only 2 wt % addition of montmorillonite brought permeability coefficients of various gases to values less than half of those of ordinary polyimide. Furthermore, this hybrid had low thermal expansion coefficient. © 1993 John Wiley & Sons, Inc.

...read more

1,363 citations


Journal ArticleDOI
TL;DR: The feasibility of using two important and common clay minerals, kaolinite and montmorillonite, as adsorbents for removal of toxic heavy metals has been reviewed.

...read more

Abstract: The feasibility of using two important and common clay minerals, kaolinite and montmorillonite, as adsorbents for removal of toxic heavy metals has been reviewed. A good number of works have been reported where the modifications of these natural clays were done to carry the adsorption of metals from aqueous solutions. The modification was predominantly done by pillaring with various polyoxy cations of Zr4+, Al3+, Si4+, Ti4+, Fe3+, Cr3+or Ga3+, etc. Preparation of pillared clays with quaternary ammonium cations, namely, tetramethylammonium-, tetramethylphosphonium- and trimethyl-phenylammonium-, N′-didodecyl-N, N′-tetramethylethanediammonium, etc, are also common. Moreover, the acid treatment of clays often boosted their adsorption capacities. The adsorption of toxic metals, viz., As, Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni, Zn, etc., have been studied predominantly. Montmorillonite and its modified forms have much higher metal adsorption capacity compared to that of kaolinite as well as modified-kaolinite.

...read more

1,131 citations


Journal ArticleDOI

1,075 citations


Network Information
Related Topics (5)
Halloysite

3K papers, 72.9K citations

93% related
Sepiolite

1.9K papers, 37.3K citations

90% related
Sorption

45.8K papers, 1.3M citations

89% related
Thermogravimetric analysis

37.2K papers, 862.1K citations

89% related
Kaolinite

8.5K papers, 224.5K citations

89% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202216
2021404
2020454
2019595
2018558
2017570

Top Attributes

Show by:

Topic's top 5 most impactful authors

Hongping He

40 papers, 3.1K citations

Jianxi Zhu

26 papers, 1.6K citations

Imre Dékány

23 papers, 933 citations

Tong‐Shuang Li

18 papers, 75 citations

Thomas J. Pinnavaia

17 papers, 1.6K citations