Mou’ad A. Tarawneh

Mechanical properties of thermoplastic natural rubber reinforced with multi-walled carbon nanotubes

This study investigated the mechanical properties of thermoplastic natural rubber (TPNR) nanocomposites reinforced by multi-walled carbon nanotubes (MWNTs). The TPNR nanocomposites were prepared using melt blending method from polypropylene, natural rubber, and liquid natural rubber as a compatibilizer, respectively, with 1—7 wt% of MWNTs. The tensile strength and Young’s modulus increased by almost 39% and 30%, respectively, at 3 wt% of MWNTs. The elongation at break decreased with increase in the percentage of MWNTs. The maximum impact strength was recorded at 5 wt% of MWNTs which was increased by 74% as compared with a pristine TPNR sample. The effect of MWNTs was also confirmed by DMA; it showed that the storage modulus E′, loss modulus E′′, and glass transition temperature (Tg) also increased for all MWNT reinforced samples. SEM micrographs confirm the effect of good dispersion of MWNTs and their interfacial bonding in TPNR.

Rice husk flour biocomposites based on recycled high-density polyethylene/polyethylene terephthalate blend: Effect of high filler loading on physical, mechanical and thermal properties

Biocomposites of recycled high-density polyethylene (rHDPE)/recycled polyethylene terephthalate (rPET) matrices with a high loading of rice husk flour (RHF) were fabricated through a two-step extrusion. The use of ethylene-glycidyl methacrylate (E-GMA) copolymer improved the compatibility of the immiscible rHDPE/rPET blend. Maleic anhydride polyethylene (MAPE) was used as a coupling agent to increase the adhesion of the fibre–matrix interface. In this study, the effect of natural fibre loadings on rHDPE/rPET blends was examined. The water absorption process in the RHF-filled composites followed the kinetics and mechanisms of Fickian diffusion. Compared with samples without RHF, the rHDPE/rPET/RHF system had 58–172% higher tensile modulus and 80–305% flexural modulus. The thermal stability of the composites slightly increased with the addition of the RHF filler. The storage modulus of biocomposites was greatly enhanced by RHF. From these results, we can conclude that RHF can work well with rHDPE/rPET for manufacturing high loading biocomposite products.

Sonication effect on the mechanical properties of MWCNTs reinforced natural rubber

This study investigated the sonication effect on the mechanical properties of thermoplastic natural rubber (TPNR) nanocomposites reinforced by multi-walled carbon nanotubes (MWCNTs). The TPNR nanocomposites were prepared using the melt blending method from polypropylene, natural rubber and liquid natural rubber as a compatibilizer, respectively, with 1% of MWCNTs. The results showed that a good dispersion on nanotubes was achieved by sonication. An optimal sonication time of 1 h was found to produce nanocomposites with maximum tensile and impact strength. The Young’s modulus, tensile strength, elongation at break and impact strength increased by almost 11%, 21%, 43% and 50%, respectively as compared with a pristine TPNR sample. The effect of sonication was also confirmed by dynamic mechanical analysis, it showed that the storage modulus E0, loss modulus E00 and glass transition temperature (Tg) also increased for all MWCNTs reinforced samples. Scanning electron micrographs confirm the effect of good dispersion of MWCNTs and their interfacial bonding in TPNR after sonication.

Thermoplastic natural rubber composites reinforced with OMMT, MWNTs, and hybrid OMMT–MWNTs

This article discusses the inclusion of MWNTs, nanoclay (OMMT), and hybrid nanofillers (MWNTs–OMMT) as reinforcing agents to improve the mechanical properties of TPNR. TPNR is a blend of PP, LNR as a compatibilizer, and NR at the percentage of volume ratio 70:10:20, respectively. The total reinforcement content is fixed at 4u2009wt%. The TPNR with 4u2009wt% OMMT, 4u2009wt% MWNTs, and hybrid 2u2009wt% OMMT2u2009wt% MWNTs was compounded using the internal mixer. The results show that the properties of the composite were improved by using the hybrid nanofillers. The tensile strength and Youngs modulus for TPNR −2u2009wt% MWNTs −2u2009wt% OMMT hybrid nanofillers are the highest compared with TPNR/4u2009wt% MWNTs, TPNR/4u2009wt% OMMT, and TPNR. However, the elongation at break considerably decreased with the hybrid nanofiller. The effect of MWNTs, OMMT, and hybrid MWNTs–OMMT was also confirmed by DMA. This showed that the storage modulus E′, loss modulus E″, and glass transition temperature (Tg) also increased for all samples reinforced with nanofillers. TEM micrographs revealed the interfacial adhesion between the fillers and the matrix, which contributed significantly to the improvement of the properties.

Investigation on the effect of NiZn ferrite on the mechanical and thermal conductivity of PLA/LNR nanocomposites

The mechanical and conductivity of magnetic polymer nanocomposite (MPNC) of nickel zinc (NiZn) ferrite nanoparticles incorporated with poly(lactic acid) (PLA) and liquid natural rubber (LNR) as compatibilizer is reported. The matrix was prepared from PLA and LNR in the ratio of 90 : 10. The MPNC of PLA/LNR/NiZn ferrite then was prepared via Thermo Haake internal mixer using melt-blending method from different filler loading from 1-5 wt% NiZn ferrite. The result of tensile tests showed that as the filler loading increases, the tensile strength also increases until an optimum value of filler loading was reached. Youngs modulus, tensile strength, and elongation at break have also increased. The study proves that NiZn ferrite is an excellent reinforcement filler in PLA/LNR matrix. The optimum thermal conductivity of PLA/LNR composites achieved with (4wt% NiZn) due to the effective combination of NiZn-NiZn conductive networks. The scanning electron micrograph (SEM) reveal that the aspect ratio and filler orientation in the PLA/LNR matrix also strongly promoted interfacial adhesion between the filler and the matrix to control its properties.

Effect of Ultrasonic Treatment on The Tensile and Impact Properties of Thermoplastic Natural Rubber Nanocomposites Reinforced with Carbon Nanotubes

This study investigates the effect of ultrasonic treatment on the mechanical properties of thermoplastic natural rubber (TPNR) nanocomposites reinforced with multi‐walled nanotubes. The TPNR nanocomposites were prepared using melt blending method from polypropylene (PP), natural rubber (NR) and liquid natural rubber (LNR) as a compatibilizer, respectively, with 1% of Multi‐wall nanotubes. The nanocomposite was prepared using the indirect technique (IDT) with the optimum processing parameters at 180°u2009C with 80 rpm mixing speed and 11 minutes processing time. The results have showed that the good dispersion on nanotubes was achieved by ultrasonic treatment. The optimization of ultrasonic time indicated that the maximum tensile and impact properties occurred with 1 h ultrasonic treatment. The Young’s modulus, tensile strength, elongation at break and impact strength have increased by almost 11%, 21%, 43% and 50%, respectively. The results from our study indicate that nanotubes have as excellent reinforcement...

Tensile and Impact Properties of Thermoplastic Natural Rubber (TPNR) Filled with Carbon Nanotubes (MWNTs)

This paper discusses the effect of multi‐walled carbon nanotubes (MWNT) on the tensile and impact properties of thermoplastic natural rubber (TPNR) nanocomposite. The nanocomposite was prepared using melt blending method. MWNT were added to improve the mechanical properties of MWNTs/TPNR composites at different compositions which is 1, 3, 5, and 7 wt.%. The result of tensile test showed that tensile strength and Young’s modulus increase in the presence of nanotubes and maximum value are obtained with 3 wt.% of MWNTs. On other hand, higher MWNTs concentration has caused the formation of aggregates. The elongation at break considerably decreased with increasing the percentage of MWNTs. The maximum impact strength is recorded with 5 wt.% of MWNTs. SEM micrograph has confirmed the homogenous dispersion of MWNTs in the TPNR matrix and promoted strong interfacial adhesion between MWNTs and the matrix which is improved mechanical significantly.

Comparison of magnetic and microwave absorbing properties between multiwalled carbon nanotubes nanocomposite, nickel zinc ferrite nanocomposite and hybrid nanocomposite

Three types of fillers were incorporated in the thermoplastic natural rubber by melt blending process. They are NiZn ferrite, multiwalled carbon nanotubes, and hybrid NiZn ferrite/multiwalled carbon nanotubes followed by weight ratio of 1:1. Their magnetic properties and microwave absorbing properties were investigated. The ball-milled techniques, resulted good filler dispersion in hybrid nanocomposite, proven by the matching saturation magnetization experimental values with the theory calculation. It was found that the magnetic property strongly depends on the amount of magnetic particles in the nanocomposites. The mixing of two different types of filler (multiwalled carbon nanotubes and NiZn ferrite) showed an enhancement of the microwave properties at lower filler loading.

The effects of gamma treatment on the mechanical properties of thermoplastic natural rubber hybrid nanocomposites

This paper discusses the effect of Gamma irradiation on the mechanical properties of thermoplastic natural rubber (TPNR) reinforced with hybrid nanofiller, multi-walled carbon nanotubes and nanoclay, (MWCNTs-OMMT). The hybrid nanocomposites samples have been subjected to gamma radiation with doses started from 0 to 200 kGy in air at room temperature. SEM micrographs revealed the fillers orientation in the TPNR matrix also promoted strongly to interfacial adhesion between fillers and the matrix which is contributed significantly to the improvement of the mechanical properties at optimum dose also the degradation of samples with high dose. The changes in the mechanical properties of hybrid nanocomposites after irradiation were attributed to the formation of crosslinks via irradiation.

CHAPTER 17:Preparation and Characterization of Natural Rubber Reinforced with Carbon Nanotubes

Incompatibility between natural rubber (NR) and polypropylene (PP) can be overcome by the introduction of a compatibilizer that can induce interactions during blending. Compatibility is important as it may affect the morphology, mechanical and thermal properties of the blends. Among the commonly used compatibilizers is a liquid natural rubber (LNR). Apart from compatibility, mixing torque and curing are interrelated in determining the homogeneity of the TPNR blend. The LNR has the same microstructure with NR but with a short chain of polyisoprene (different in molecular weight, Mw). The LNR with some active terminals like –OH is expected to react with the plastic particles and thereby bond the plastic particles to the NR matrix. In this chapter, thermoplastic natural rubber TPNR reinforced with multi-walled carbon nanotube (MWCNTs) nanocomposites was prepared by the melt blending method. Using this method, MWCNTs will be dispersed homogeneously in the TPNR matrix in an attempt to increase the properties of these nanocomposites. The effect of MWCNTs on the mechanical and thermal properties of TPNR nanocomposites is reported in this chapter.