Structure and Properties of Natural Rubber and Modified Montmorillonite Nanocomposites

2003 ◽  
Vol 76 (2) ◽  
pp. 406-418 ◽  
Author(s):  
Rathanawan Magaraphan ◽  
Woothichai Thaijaroen ◽  
Ratree Lim-ochakun
Keyword(s):  
Mechanical Properties ◽  
Natural Rubber ◽  
Clay Content ◽  
Silicate Layer ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Silicate Layers ◽  
High Structure ◽  
Natural Rubber Vulcanizates

Abstract Montmorillonite clay was organically modified by primary and quaternary ammonium salts (having C12-C18). The modified clay was added to a solution of natural rubber in toluene at various contents. Characterization of the structure of the nanocomposites was performed by using x-ray diffraction and transmission electron microscope. The results showed that the silicate layers of the clay were expanded so that the exfoliated nanocomposites were obtained at clay content below 10 phr; above that the nanocomposites became partially exfoliated. Moreover, long primary amine showed more improved mechanical properties than the quaternary one (at the same carbon numbers). The longer organic modifying agents resulted in better expansion of silicate layer distance indicating more intercalation of natural rubber molecules in between clay galleries. The curing properties were also improved. It was found that a small loading of 7 phr is enough to bring good mechanical properties in comparison to those of high structure silica filled and carbon black filled natural rubber vulcanizates.

MECHANICAL PROPERTIES OF A POLYURETHANE/MONTMORILLONITE NANOCOMPOSITE FEATURING ORGANOMODIFICATION SYNTHESIZED VIA IN SITU POLYMERIZATION

2015 ◽  
Vol 88 (1) ◽  
pp. 138-146 ◽  
Author(s):  
Rouhollah Bagheri ◽  
Reza Darvishi
Keyword(s):  
Mechanical Properties ◽  
In Situ Polymerization ◽  
Xrd Analysis ◽  
Silicate Layer ◽  
X Ray Diffraction ◽  
X Ray ◽  
End Groups ◽  
Layer Sample ◽  
Silicate Layers

ABSTRACT In this study, polyurethane (PU)/organomodified montmorillonite (cloisite®30B) is synthesized via in situ polymerization by reaction of an ether-based prepolymer with the isocyanate end groups and adiamine chain extender (4, 4-methylene-bis(2-chloroaniline)) in the presence of different amounts of nanoparticles dispersed in the prepolymer matrix by an ultrasonic mixer for 1 h. The synthesized polymers are cast on a pretreated carbon steel sheet and cured at 120 °C in an oven. The PU and its composites have been characterized by using Fourier transform infrared spectroscopy, X-ray diffraction (XRD), and mechanical testing. The XRD analysis of the cured samples containing 1 to 3 wt% cloisite30B showed intercalation segments in the silicate layers and exfoliation for 0.5 wt% nanoparticles. The highest mechanical properties were obtained using the cured exfoliated silicate layer sample. A twofold increase in the ultimate tensile strength and a 2.3 times increase in the adhesion strength were found for 0.5 wt% organoclay/PU as compared with that of pure PU. In addition, the exfoliated structure sample exhibited a 16% reduction in abrasion compared with that of pure PU.

Synthesis and Characterization of Polystyrene-Graphite Nanocomposites via Surface Raft-Mediated Polymerization

2012 ◽  
Vol 463-464 ◽  
pp. 527-532
Author(s):  
Hussein M. Etmimi ◽  
Ronald D. Sanderson
Keyword(s):  
Mechanical Properties ◽  
Miniemulsion Polymerization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Reversible Addition ◽  
Raft Agent ◽  
Polymerization Method ◽  
Better Than

The synthesis of polystyrene/GO (PS-GO) nanocomposites using the reversible addition-fragmentation chain transfer (RAFT) mediated polymerization method is described. The GO was synthesized and immobilized with a RAFT agent to afford RAFT-functionalized GO nanosheets. The RAFT-immobilized GO was used for the synthesis of PS nanocomposites in a controlled manner using miniemulsion polymerization. The moelcular weight and dispersity of the PS in the nanocomposites depended on the amount of RAFT-grafted GO in the system, in accordance with the features of the RAFT-mediated polymerization. X-ray diffraction and transmission electron microscopy analyses revealed that the nanocomposites had exfoliated morphology, even at relatively high GO content. The thermal stability and mechanical properties of the PS-GO nanocomposites were better than those of the neat PS polymer. Furthermore, the mechanical properties of the nanocomposites were dependent on the RAFT grafted GO content.

IMPROVEMENT IN PHYSICAL AND MECHANICAL PROPERTIES OF IIR/CR RUBBER BLEND ORGANOCLAY NANOCOMPOSITES

2014 ◽  
Vol 87 (1) ◽  
pp. 10-20 ◽  
Author(s):  
M. J. Azizli ◽  
G. Naderi ◽  
G. R. Bakhshandeh ◽  
S. Soltani ◽  
F. Askari ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Polymer Chains ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Roll Mill ◽  
Chloroprene Rubber ◽  
Cr Concentration ◽  
Silicate Layers

ABSTRACT The effects of organoclay loading and chloroprene rubber (CR) concentration on the cure characteristics, microstructure, and mechanical and rheological properties of isobutylene–isoprene rubber (IIR)/CR blend were investigated. Different compositions of CR (10, 20, and 40 wt%) with Cloisite15A as organo modified nanoclay (1, 3, 5, and 7 wt%) were used for blends by a two-roll mill. Samples were vulcanized at 175 °C using a hot press. The cure and scorch times and also the maximum torque of the composites increased with the incorporation of organoclay. Mechanical properties such as tensile strength, elongation at break, modulus (100%, 200%, and 300%), and resilience improved with increasing nanoclay loading. The structure of the nanocomposites was characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). XRD results of nanocomposites indicated that the intercalation of polymer chains into the clay gallery was deduced from increasing the interlayer distance of silicate layers. TEM and SEM also directly confirmed XRD results.

Preparation and Characterization of Thermoplastic Vulcanizates-Organoclay Nanocomposites

2005 ◽  
Vol 480-481 ◽  
pp. 333-338 ◽  
Author(s):  
B. Herrero ◽  
M. Arroyo ◽  
Miguel A. López-Manchado
Keyword(s):  
Mechanical Properties ◽  
X Ray Diffraction ◽  
Ethylene Propylene ◽  
X Ray ◽  
Modified Montmorillonite ◽  
Thermoplastic Vulcanizates ◽  
The Matrix ◽  
Silicate Layers ◽  
Ethylene Propylene Diene Terpolymer

Thermoplastic vulcanizates nanocomposites based on polypropylene (PP) and ethylene–propylene-diene terpolymer rubber (EPDM) blends reinforced with organoclay modified montmorillonite have been prepared via melt intercalation. The silicate layers of the clay were intercalated and dispersed at a nanometer level in the matrix blends. The nanocomposites exhibit improved mechanical properties, this effect being more evident at high EPDM contents in the blend (above 80%). This behavior is attributed to the fact that the EPDM chains are more easily inserted into the galleries silicate, giving rise to a more intercalated structure as was observed by X-ray diffraction.

Preparation of cross-linked PVC-g-(St-MA) copolymer/organoclay nanocomposites and investigation of chemical characteristics, morphology, thermal, and mechanical properties

2019 ◽  
pp. 089270571988601
Author(s):  
Reza Izadpanah ◽  
Mostafa Rezaei ◽  
Saeid Talebi
Keyword(s):  
Mechanical Properties ◽  
Clay Content ◽  
Thermomechanical Properties ◽  
Morphological Observation ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Bonding Interaction ◽  
Structure Morphology ◽  
Nanoclay Content

The goal of this work is to investigate the effect of incorporating organoclays on the cross-link structure, morphology, and thermomechanical properties of cross-linked organoclay/polyvinyl chloride grafted with styrene and maleic anhydride (PVC- g-(St-MA)) copolymer nanocomposites (CPN). Cloisite30B (C30B) and Cloisite15A (C15A) organoclays were used for the preparation of cross-linked PVC- g-(St-MA) nanocomposites by the solution mixing route. The nanoclay content in nanocomposites varied from 0.2 wt% to 1 wt%. The chemical structure and interaction between PVC- g-(St-MA) cross-linked segments and nanoclays were studied by Fourier transform infrared (FTIR) peaks deconvolution method. FTIR spectroscopy suggested the lowest extent of hydrogen bonding interaction for C30B containing sample, which decreased with clay content increment. The morphology of nanocomposites was studied by X-ray diffraction and transmission electron microscopy methods. Morphological observation revealed a near to the exfoliation state for organoclays in PVC- g-(St-MA) nanocomposite containing 1 wt% C30B. However, C15A/PVC- g-(St-MA) nanocomposite (C15A-CPN) exhibited partially intercalated and agglomerated morphology. Differential scanning calorimetry examination was conducted to measure the glass transition temperature ( T g) of the segments. At the same clay content, the T g of the C30B containing nanocomposites were higher than that of C15A samples. The mechanical properties of these nanocomposites were also investigated. As a consequence, C30B-CPN showed improved mechanical properties compared to C15A-CPN and cross-linked PVC- g-(St-MA) samples.

Mechanical and Morphological Properties Evaluation of HDPE/Organoclay Nanocomposites with Various Percentages of NR Content

2011 ◽  
Vol 471-472 ◽  
pp. 115-120
Author(s):  
Engku Zaharah Engku Zawawi ◽  
Ahmad Haji Sahrim ◽  
Rozaidi Rashid
Keyword(s):  
Mechanical Properties ◽  
Natural Rubber ◽  
Morphological Properties ◽  
Silicate Layer ◽  
X Ray ◽  
Transmission Electron ◽  
The Matrix ◽  
Izod Impact ◽  
Thermoplastic Natural Rubber ◽  
Internal Mixer

Nanocomposites prepared from blend of high density polyethylene (HDPE), natural rubber (NR) and organoclay were melt compounded using an internal mixer. The phase morphology and mechanical properties of this thermoplastic natural rubber nanocomposites samples were examined. The transmission electron microscope (TEM) and wide angle X-ray scattering (WAXS) was used to determine the exfoliation of organoclay in this blend. The tensile and Izod impact test were used to evaluate the mechanical properties of HDPE/organoclay nanocomposites with and without the presence of NR. The Izod impact results shows an improvement more than 300% with addition of 10% NR content in the matrix. The X-ray diffraction results indicated intercalation of blend into the silicate interlayer of nano-filler I.44P and partially exfoliation of silicate layer into the blend. The SEM morphology revealed that there was some part of uneven dispersion of organoclay in the blend.

scholarly journals Preparation and Characterization of Polyurethane Nanocomposites Using Vietnamese Montmorillonite Modified by Polyol Surfactants

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
C. N. Ha Thuc ◽  
H. T. Cao ◽  
D. M. Nguyen ◽  
M. A. Tran ◽  
Laurent Duclaux ◽  
...  
Keyword(s):  
Mechanical Performance ◽  
Thermoplastic Polyurethane ◽  
Silicate Layer ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Thermal Stabilities ◽  
Transmission Electron ◽  
Clay Layers ◽  
Urethane Linkage

This study focuses on the preparation of thermoplastic polyurethane (TPU) nanocomposite using Vietnamese montmorillonite (MMT) as the reinforced phase. The MMT was previously modified by intercalating polyethylene oxide (PEO) and polyvinyl alcohol (PVA) molecules between the clay layers. X-ray diffraction (XRD) results of organoclays revealed that galleries of MMT were increased to 18.2 Å and 27 Å after their intercalation with PEO and PVA, respectively. Thermoplastic polyurethane (TPU) nanocomposites composed of 1, 3, 5, and 7%wt organoclays were synthesized. The result of XRD and transmission electron microscopic (TEM) analyses implied that the PEO modified MMT was well dispersed, at 3%wt, in polyurethane matrix. Fourier Transform Infrared Spectroscopic (FTIR) has confirmed this result by showing the hydrogenous interaction between the urethane linkage and OH group on the surface of silicate layer. Thermogravimetric (TG) showed that the organoclay samples also presented improved thermal stabilities. In addition, the effects of the organoclays on mechanical performance and water absorption of the PU nanocomposite were also investigated.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

High Resolution Replication of Organoclay Surfaces

1982 ◽  
Vol 40 ◽  
pp. 576-577
Author(s):  
W. W. Barker ◽  
W. E. Rigsby ◽  
V. J. Hurst ◽  
W. J. Humphreys
Keyword(s):  
Clay Mineral ◽  
Organic Molecule ◽  
Organic Molecules ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Naturally Occurring ◽  
Silicate Layers ◽  
Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

scholarly journals Effects of Sintering Temperature on Densification, Microstructure and Mechanical Properties of Al-Based Alloy by High-Velocity Compaction

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 218
Author(s):  
Xianjie Yuan ◽  
Xuanhui Qu ◽  
Haiqing Yin ◽  
Zaiqiang Feng ◽  
Mingqi Tang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Velocity ◽  
Sintered Density ◽  
Sintering Temperature ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron ◽  
High Velocity Compaction ◽  
Sintered Temperature

This present work investigates the effects of sintering temperature on densification, mechanical properties and microstructure of Al-based alloy pressed by high-velocity compaction. The green samples were heated under the flow of high pure (99.99 wt%) N2. The heating rate was 4 °C/min before 315 °C. For reducing the residual stress, the samples were isothermally held for one h. Then, the specimens were respectively heated at the rate of 10 °C/min to the temperature between 540 °C and 700 °C, held for one h, and then furnace-cooled to the room temperature. Results indicate that when the sintered temperature was 640 °C, both the sintered density and mechanical properties was optimum. Differential Scanning Calorimetry, X-ray diffraction of sintered samples, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, and Transmission Electron Microscope were used to analyse the microstructure and phases.

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