Influence of Bentonite Clay Content in HDPE Nanocomposites

2012 ◽  
Vol 727-728 ◽  
pp. 1780-1784
Author(s):  
Sara Verusca de Oliveira ◽  
Milena Costa da Silva ◽  
Gustavo Figueiredo Brito ◽  
Antônio Gilson Barbosa de Lima ◽  
Edcleide Maria Araújo

This research is to obtain nanocomposites of HDPE/bentonite clay. Inorganic polymers reinforced with materials are of great interest due to their applications in automotive, and electrical and electronic industries. The nanocomposites were produced by melt intercalation with different percentages of clay and compared with pure HDPE. Clay was used as modified and unmodified and it was characterized by X-ray diffraction (XRD) and X-ray fluorescence (XRF). The obtained nanocomposites were characterized through thermogravimetry (TG). It was verified by XRF that clay performed compositions of bentonites characteristics. By XRD, it was observed increases basal spacing for organoclay. By TG, in general, it was verified that the nanocomposites presented greater thermal stability in relation to HDPE.

2012 ◽  
Vol 727-728 ◽  
pp. 899-903 ◽  
Author(s):  
Keila Machado Medeiros ◽  
Taciana Regina de Gouveia Silva ◽  
Luana Rodrigues Kojuch ◽  
Edcleide Maria Araújo ◽  
Hélio Lucena Lira

Bentonites are the most used fillers in the development of nanocomposites, due to their characteristics that provide nanosized particles, contributing to a large contact area between the clay and the polymer. In general, the additions of small amounts of organoclay improve the mechanical and thermal properties of nanocomposites. Bentonite clays and organoclays were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG). The results of XRF, XRD and FTIR confirmed the presence of quaternary ammonium salt in the organoclay structure. From TG, it was observed that the organoclay showed better thermal stability when compared with bentonite clay.


2014 ◽  
Vol 917 ◽  
pp. 115-122 ◽  
Author(s):  
Ali E.I. Elkhalifah ◽  
Mohammad Azmi Bustam ◽  
Mohd Shariff Azmi ◽  
T. Murugesan

A series of organic-inorganic hybrids were developed via intercalation process of primary, secondary and tertiary ammonium cations into different alkali and alkaline earth and transition metal cation forms of bentonite clay to be used as adsorbent materials for CO2capture under ambient temperature and slightly high pressure. The effect of the molar mass of amines on the structural characteristics, surface properties and CO2loading capacity of bentonite clay were investigated by X-ray diffraction, Brunauer-Emmett-Teller method and Magnetic Suspension Balance equipment, respectively. X-ray diffraction results revealed that the basal spacing of bentonite clay after modification with amines was increased with the molar mass of amine used, while BET results showed an inverse effect of the molar mass of amines on the surface area of the synthesized materials. The CO2loading capacity of the examined samples revealed that bentonite clay modified with monoethanolammonium cations retained higher CO2amount compared to those modified with di-and triethanolammonium cations. CO2adsorption isotherms on MEA+-Mg-MMT were conducted at 298, 323 and 348 K and different pressures. A decrease in CO2uptake with increasing temperature was observed, suggesting the exothermic nature of the adsorption process.


2021 ◽  
Vol 7 (5) ◽  
pp. 2010-2018
Author(s):  
Olukayode Gideon Oloyede ◽  
◽  
Umar Omeiza Aroke ◽  
Saidat Olanipekun Giwa ◽  
Alexander Asanja Jock ◽  
...  

In this study, Dijah-Monkin bentonite clay was modified with a cationic surfactant hexadecyltrimethylammonium bromide (HDTMA-Br) at the level of twice the cation exchange capacity (CEC). This process results in the development of hydrophobic organoclay with an improved adsorption capacity. The clay obtained from Zing LGA Taraba State, North-East Nigeria, was beneficiated and pulverised to a particle size of 125 µm. The modification was performed without acid activation to prevent damages to the clay’s crystal structure. The organoclay was characterised for chemical composition, functional groups, mineralogical and surface morphology using X-ray fluorescence (XRF), Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The XRD showed an increase in the basal spacing from 15.681Å to 17.758 Å, while the XRF revealed a 5.35% concentration of Br on the modified clay, indicating successful intercalation. The FTIR spectra also revealed the appearance of symmetric and asymmetric stretching bands at 2847.7cm-1 and 2914.8cm-1, respectively, as a consequence of the modification, resulting in more sites for adsorption.


2014 ◽  
Vol 775-776 ◽  
pp. 357-362
Author(s):  
Renata Barbosa ◽  
Tatianny Soares Alves ◽  
Dayanne Diniz Souza Morais ◽  
Laura Hecker Carvalho ◽  
Osanildo Damião Pereira

The consumption of plastic products over the years has been producing large numbers of waste material, which accumulate by landfill generating considerable environmental problems. Among biodegradable polymers, there is the PHB (poly-3-hydroxybutyrate), which has attracted more attention once it is obtained from renewable sources. This study aimed to prepare biodegradable nanocomposites by melt intercalation of PHB polymer in the natural vermiculite clay, in the ratios of 1, 3 and 6 wt%. The nanocomposites were obtained in an internal mixer coupled to a torque rheometer by Haake-Blucher, operating at 170°C, 50 rpm for 10 minutes. The material was triturated and then films were molded by compression under the conditions: 3 tons at 170°C for 3 minutes. The films were characterized by X-ray diffraction (XRD) and Infrared (FTIR). These analyzes were used to evaluate the intercalation and / or exfoliation of nanocomposites. In general, results indicated changes in structure as a function of clay content employed in the systems of PHB / vermiculite.


2008 ◽  
Vol 15 (03) ◽  
pp. 329-336 ◽  
Author(s):  
YIMIN ZHANG ◽  
SHAOXIAN SONG ◽  
MIN ZHANG ◽  
BIYANG TUO

In this work, a Ti -pillared montmorillonite with high thermal stability has been prepared by using a Na -montmorillonite as the host clay and polyhydroxy-titania ions as the pillaring precursor. The formation of Ti -pillared montmorillonite has been confirmed from the characterizations through X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric–differential scanning calorimeter, and specific surface area analyses. In the preparation of Ti -pillared montmorillonite several parameters, such as the type of solvent in which the synthesis is realized, the ratio of polyhydroxy-titania ions and montmorillonite, the intercalation time, the calcining temperature, and calcining time, were tested to understand their effects on the basal spacing. It was shown that this method could produce a Ti -pillared montmorillonite with the basal spacing of 3.74 nm, specific surface area of 409 m2/g, and mean pore size of 2.94 nm, as well as a high thermal stability up to 900°C.


Clay Minerals ◽  
2009 ◽  
Vol 44 (1) ◽  
pp. 35-50 ◽  
Author(s):  
Yun Huang ◽  
Xiaoyan Ma ◽  
Guozheng Liang ◽  
Hongxia Yan

AbstractMelt blending using a twin-screw extruder was used to prepare composites of polypropylene (PP)/organic rectorite (PR). The organic rectorite (OREC) was modified with dodecyl benzyl dimethyl ammonium bromide (1227). Wide-angle X-ray diffraction (WAXD) and transmission electron microscopy were used to investigate the dispersion of OREC in the composites. The d spacings of OREC in PR composites was greater than in OREC itself. The dispersion of OREC particles in the PP polymer matrix was fine and uniform when the clay content was small (2 wt.%). The rheology was characterized using a capillary rheometer. The processing behaviour of the PR system improved as the amount of OREC added increased. Non-isothermal crystallization kinetics were analysed using differential scanning calorimetry. It was shown that the addition of OREC had a heterogeneous nucleation effect on PP, and can accelerate the crystallization. However, only when fine dispersion was achieved, and at lower rates of temperature decrease, was the crystallinity greater. Wide-angle X-ray diffraction and polarized light microscopy were used to observe the crystalline form and crystallite size. The PP in the PR composites exhibited an a-monoclinic crystal form, as in pure PP, and in both cases a spherulite structure was observed. However, the smaller spherulite size in the PR systems indicated that addition of OREC can reduce the crystal size significantly, which might improve the ‘toughness’ of the PP. The mechanical properties (tensile and impact strength) improved when the amount of OREC added was appropriate. Dynamic mechanical analysis showed that the storage modulus (E′) and loss modulus (E″) of the nanocomposites were somewhat greater than those of pure PP when an appropriate amount of OREC was added. Finally, thermogravimetric analysis showed that the PR systems exhibited a greater thermal stability than was seen with pure PP.


1998 ◽  
Vol 514 ◽  
Author(s):  
M. F. Wu ◽  
A. Vantomne ◽  
S. Hogg ◽  
H. Pattyn ◽  
G. Langouche ◽  
...  

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.


2021 ◽  
Vol 875 ◽  
pp. 116-120
Author(s):  
Muhammad Alamgir ◽  
Faizan Ali Ghauri ◽  
Waheed Qamar Khan ◽  
Sajawal Rasheed ◽  
Muhammad Sarfraz Nawaz ◽  
...  

In this study, the effect of SBR concentration (10 Phr, 20 Phr & 30 Phr ) on the thermal behavior of EPDM/SBR blends was studied. Thermogravimetric analysis (TGA) was used to check weight loss of samples as function of temperature by heating upto 600°C. X-ray diffraction (XRD) was performed to determine quality and % crystallinity of the elastomer blends. It was seen that % crystallinity improved with an increase in the content of SBR in EPDM/SBR blends. TGA revealed that the thermal stability of EPDM/SBR blends has improved by 17% than neat EPDM. Carbon nano-coatings produced by sputtering have no beneficial influence on thermal behaviour of elastomers.


2018 ◽  
Vol 6 (24) ◽  
pp. 11496-11506 ◽  
Author(s):  
Paul Pistor ◽  
Thomas Burwig ◽  
Carlo Brzuska ◽  
Björn Weber ◽  
Wolfgang Fränzel

We present the identification of crystalline phases by in situ X-ray diffraction during growth and monitor the phase evolution during subsequent thermal treatment of CH3NH3PbX3 (X = I, Br, Cl) perovskite thin films.


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