Murugasamy Kannan

Nanoclay effect on transport properties of thermoplastic polyurethane/polypropylene (TPU/PP) blends

In this paper the diffusion of water through the nanoclay filled TPU/PP blends was investigated at various temperatures. The effect of blend ratio, compatibilisation and nanoclay addition on the transport properties was studied in detail. Special attention has been given to study the mechanism of diffusion. Thermodynamics and Arrhenius parameters were evaluated from the diffusion data. The various parameters such as diffusion coefficient (D), permeation coefficient (P), sorption coefficients (S) were evaluated at different diffusion conditions. Attempts were made to correlate the observed morphology of the blends with transport properties. Addition of PP into TPU decreases water sorption of the system due to the decrease in overall polarity of the system and further reduced by addition of compatibiliser and nanoclay into the system. Compared to the ether-TPU based blend nanocomposites, the ester-TPU blends show better compatibility as confirmed by analysis.

Mechanical Properties and Morphology of Nanoclay-Filled Different TPU/PP Blends

Thermoplastic polyurethanes (TPU) (based on ether and ester polyols) were blended with nonpolar material of PP. Nanoclay was used to reduce the surface energy of the TPU hard segments and makes them more compatible with the non-polar PP. More compatible blends have been obtained by using MA-g-PP as the compatibiliser. Blends were produced by melt mixing using a twin crew extruder. Compared to the ether-TPU based blend nanocomposites, the ester–TPU blends show better compatibility as confirmed by DMA, Tensile strength, XRD, SEM, and AFM analysis.

Thermomechanical behavior of nanoclay filled TPU/PP blends

Abstract Both 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.

Mechanical Properties and Morphology of Nanoclay Filled Different TPU/PP Blend Nanocomposites: Structure - Property Relations

Thermoplastic polyurethanes (TPU) (based on ether and ester polyols) were blended with nonpolar polypropylene (PP). Nanoclay was used to reduce the surface energy of the TPU hard segments and make them more compatible with the nonpolar PP. More compatible blends were obtained by using MA-g-PP as the compatibilizer. Blends were produced by melt mixing using a twin screw extruder. Compared to the ether-TPU-based blend nanocomposites, the ester-TPU blends show better compatibility as confirmed by DMA, Tensile strength, XRD, SEM, and AFM analysis.

Microstructure Development, Wear Characteristics and Kinetics of Thermal Decomposition of Hybrid Nanocomposites Based on Poly Aryl Ether Ketone, Boron Carbide and Multi Walled Carbon Nanotubes

In the present study a high performance polymer poly aryl ether ketone (PAEK) is reinforced with micro and nano boron carbide (B4C) and functionalized multi walled carbon nanotubes (F-MWCNT) to investigate the individual and hybrid effect of the fillers. Optical microscopy and transmission electron microscopy suggested the dispersion of micro and nano fillers respectively in PAEK matrix. The inclusion of B4C nano fillers increased the hardness of the composites which aided the wear resistance of the composites. The morphological features of the worn surface of the samples are analyzed using scanning electron microscopy. It is found from the izod impact test analysis that the impact strength of the composite enhanced by the F-MWCNT inclusion. The thermal properties of PAEK in the composites are studied using differential scanning calorimetry and it revealed dominant effect of F-MWCNT influencing the thermal transitions than the B4C particles. The kinetics of thermal degradation of various composites is analyzed using Coats–Redfern method. The positive influence of B4C in the matrix indicates that the thermal degradation is delayed due to the higher activation energy it possesses. The overall results shows that the hybrid nanocomposite exhibits better properties compared to individual micro and nano composites.

Dynamic mechanical properties of nanoclay filled TPU/PP blends with compatibiliser

Abstract Blends of thermoplastic polyurethane (TPU) and polypropylene (PP) are highly incompatible because of large differences in polarities and high interfacial tensions. On one hand, PP is added to TPU to improve TPUs thermal stability, chemical properties, mechanical properties (modulus, strength and hardness) and processing performance and to reduce TPUs cost. On the other hand, TPU is blended with PP to improve PPs properties (e.g. abrasion, flexibility, tear strength, shock absorbing capabilities, impact strength, adhesion and paintability/printability). Earlier works in polyurethane/organoclay nanocomposites, PP/organoclay nanocomposites and TPU/PP blends were studied. In our experimental work, both ester and ether based TPU nanocomposites were prepared by melt blending using 3 wt-% Cloisite 10A (organically modified montmorillonite clay) as the nanoscale reinforcement and blended with PP with/without PP-graft-maleic anhydride as the compatibiliser. Blends of nanoclay filled TPU/PP were evaluated for dynamic mechanical properties such as storage modulus E′, loss modulus E″ and dissipation factor tanδ.