The Mechanical and Thermal Properties of Polyoxymethylene (POM)/Organically Modified Montmorillonite (OMMT) Engineering Nanocomposites Modified with Thermoplastic Polyurethane (TPU) Compatibilizer

2012 ◽  
Vol 714 ◽  
pp. 201-209 ◽  
Author(s):  
Agnieszka Leszczyńska ◽  
Krzysztof Pielichowski
Keyword(s):  
Thermal Properties ◽  
Formic Acid ◽  
Mass Loss ◽  
Thermoplastic Polyurethane ◽  
Layered Silicate ◽  
Thermal Stabilization ◽  
Mechanical And Thermal Properties ◽  
Modified Montmorillonite ◽  
Organically Modified Montmorillonite ◽  
Organically Modified

In this work the effect of macromolecular polyurethane compatibilizer on the structure, mechanical and thermal properties of polyoxymethylene/organically modified montmorillonite (POM/OMMT) nanocomposites was investigated. The thermal stability of obtained systems was significantly enhanced by compatibilizer both in oxidative and inert atmosphere. The thermoanalytical methods (TG-FTIR and TG-MS) were used for identification of gaseous products of degradation. The results showed less intensive evolution of formaldehyde and formic acid during the thermal degradation of POM/TPU/OMMT nanocomposites. Both formaldehyde and formic acid had an autocatalytic effect on degradation of neat POM and POM/MMT nanocomposites, especially in the initial stage of the process. However, in the presence of TPU the monomer formed in depolymerization reaction was captured most probably by urethane linkage in a formylation process. The decreased concentration of catalytic agent is considered as a cause of the reduced rate of mass loss of POM/TPU/OMMT nanocomposites. Interestingly, during thermooxidative degradation the temperature of maximum rate of mass loss was shifted towards higher temperature more than it could be anticipated from the TGA results obtained for neat POM, POM/TPU blend and POM/OMMT nanocomposite material with corresponding contents of nanofiller and compatibilizer. It is likely that the mechanism of thermal stabilization may be also related to the physical barrier effect of layered silicate towards oxygen diffusion. Both chemical and physical mechanisms of stabilization are referred to the structure and interfacial area developed in nanocomposite materials and thus can be influenced by addition of a compatibilizer. The obtained POM/TPU/OMMT nanocomposites revealed higher impact strength as compared to POM/OMMT materials due to the presence of elastomeric domains facilitating the dissipation of impact energy.

Effect of Polysulfone/Organomontmorillonite Blends on Nanocomposite Membrane Properties

2019 ◽  
Vol 801 ◽  
pp. 331-336
Author(s):  
Ruth R. Aquino ◽  
Marvin S. Tolentino ◽  
Mira L. Esmalde ◽  
Dara Veromica B. Condol ◽  
Blessie A. Basilia
Keyword(s):  
Thermal Properties ◽  
Clay Content ◽  
Membrane Properties ◽  
Mechanical And Thermal Properties ◽  
Sem Images ◽  
Modified Montmorillonite ◽  
Organically Modified Montmorillonite ◽  
Significant Difference ◽  
Organically Modified ◽  
Improved Characteristics

In this study, an organically modified montmorillonite (OMMT) hydrophilic clay was incorporated in PSf through non-solvent induced phase separation fabrication process to improve its properties. Afterwards, hand casting was done and the PSf/OMMT membranes produced were characterized to determine the effect of OMMT addition to its structural, mechanical and thermal properties, and hydrophilicity. Scanning electron microscope (SEM) images of the surfaces showed a denser surface as the OMMT content increases but the pores on the images were not pronounced unlike the SEM images of the cross-section which depicted spherical macrovoids for 1.0% while wider macrovoids were observed for 3.0% and 5.0% OMMT. The mechanical properties of the nanocomposite with clay content up to 3.0% were improved. The glass transition temperatures of the PSf/OMMT nanocomposites were lower than the pure PSf while no significant difference was observed for the melting point. By statistical analysis, the addition and variation of the clay concentrations has no significant effect to the thermal properties. The hydrophilicity of the membranes improved with the increasing OMMT concentration, but was found to be insignificant. The overall data gathered showed that the clay addition had improved characteristics compared to the pure PSf membrane, which implies that PSf/OMMT nanocomposite could be likely used in filtration applications.

Biodegradable Polyester / Layered Silicate Nanocomposites

2002 ◽  
Vol 740 ◽  
Author(s):  
Pralay Maiti ◽  
Carl A. Batt ◽  
Emmanuel P. Giannelis
Keyword(s):  
Mechanical Properties ◽  
Storage Modulus ◽  
Layered Silicate ◽  
Layered Silicates ◽  
Melt Extrusion ◽  
Biodegradable Polyester ◽  
Modified Montmorillonite ◽  
Organically Modified Montmorillonite ◽  
Silicate Nanocomposites ◽  
Organically Modified

ABSTRACTNanocomposites of α-hydroxy polyester, polylactide (PLA) and β-hydroxy polyester, polyhydroxybutyrate (PHB) with layered silicates have been successfully prepared by melt extrusion of PLA and PHB with organically modified montmorillonite (MMT) and fluoromica. The mechanical properties of the nanocomposites are improved compared to the neat polymers. Storage modulus increase up to 40% compared with the pure polymers by adding only 2–3 wt% nanoclay. Biodegradation can be controlled by the choice of the nanoclay used.

Nanocomposites Based on Montmorillonite/Acrylic Copolymer for Aqueous Coating of Soft Surfaces

2009 ◽  
Vol 151 ◽  
pp. 129-134 ◽  
Author(s):  
Onur Yılmaz ◽  
Aurica P. Chiriac ◽  
Catalina Natalia Cheaburu ◽  
Loredana E. Nita ◽  
Gürbüz Gülümser ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Layered Silicate ◽  
Acrylic Copolymer ◽  
Modified Montmorillonite ◽  
Organically Modified Montmorillonite ◽  
Film Forming ◽  
Organically Modified ◽  
Polymerization Method ◽  
Structural Characterizations

Nanocomposites based on layered silicate organically modified montmorillonite (Cloisite 20A) and acrylic comonomers (butyl acrylate and methyl methacrylate) were prepared by simple “in situ” batch emulsion polymerization method. The particle size and zeta potential of the emulsions were analyzed. The structural characterizations of the nanocomposites were performed by FTIR, thermal behaviors of the films were investigated by DSC, mechanical properties of the films were tested by DMA and intercalation success was viewed by XRD. The mechanical properties of the nanocomposites were improved significantly especially at the temperatures above Tg. The ultrasonication process was found to be useful for increasing the homogeneity of the emulsions and intercalation success. The obtained nanocomposite emulsions were applied on garment leathers in a finishing formulation as aqueous binders sharing good film forming ability and elasticity.

Thermomechanical behavior of nanoclay filled TPU/PP blends

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
M. Kannan ◽  
S.S. Bhagawan ◽  
Kuruvilla Joseph ◽  
Sabu Thomas
Keyword(s):  
Hard Segment ◽  
Thermoplastic Polyurethane ◽  
Melt Blending ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Modifier ◽  
Modified Montmorillonite ◽  
Organically Modified Montmorillonite ◽  
Organically Modified ◽  
Pp Blends

AbstractBoth ester- and ether- based thermoplastic polyurethane (TPU) nanocomposites were prepared by melt blending, using 3 wt % Cloisite 10A (organically modified montmorillonite clay) as the nanoscale reinforcement. The nanocomposites were subsequently melt-blended with polypropylene (PP) using maleic anhydride grafted polypropylene (MA-g-PP) as a compatibilizer (in the ratio of 70/30- TPU nano/PP, 70/25/5-TPU nano/PP/MA-g-PP). Besides giving substantial increase in modulus, tensile strength and other properties organoclay reinforcement functions as a surface modifier for TPU hard segment. X-ray diffraction studies revealed that compatibilization is further improved by introducing functionalized PP (MA-g-PP) in the organoclay containing blends. The blend system was evaluated by DSC, DMA, SEM, mechanical properties and Xray diffraction. The results indicate that the ester- TPU exhibited greater miscibility than ether-TPU. Abrasion resistance and water absorption were also better for compatibilised ester- TPU blends as compared to the ether-TPU materials.

scholarly journals Thermal Stability and Degradation Kinetics of Polystyrene/Organically-Modified Montmorillonite Nanocomposites

2008 ◽  
Vol 8 (4) ◽  
pp. 1927-1936 ◽  
Author(s):  
Grace Chigwada ◽  
Everson Kandare ◽  
Dongyan Wang ◽  
Stephen Majoni ◽  
Darlington Mlambo ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Mass Loss ◽  
Degradation Kinetics ◽  
X Ray Diffraction ◽  
Cone Calorimetry ◽  
Model Free ◽  
Modified Montmorillonite ◽  
Organically Modified Montmorillonite ◽  
Transmission Electron ◽  
Organically Modified

Organically-modified montmorillonite (MMT) clays have been prepared using ammonium salts containing quinoline, pyridine, benzene, and styrenic groups. The nanocomposites were prepared by melt blending and the formation of nanocomposites was characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Thermal stability and flammability were evaluated by thermogravimetric analysis (TGA) and cone calorimetry measurements, respectively. The presence ofmodified MMT at 5% loading resulted in significant improvement in thermal stability compared to the virgin polymer. Effective activation energies for mass loss were determined via a model-free isoconversional approach from TGA data obtained under N2 and under air. The additives served to raise the activation energy, with a more significant impact observed under pyrolysis conditions. The onset temperature of degradation and temperature of maximum decomposition rate are increased, while the peak heat release rate and mass loss rates are significantly reduced in the presence of three of the modified clays. No reduction in the total heat released is observed.

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