scholarly journals Influence of Multiwalled Carbon Nanotubes on the Rheological Behavior and Physical Properties of Kenaf Fiber-Reinforced Polypropylene Composites

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2083
Author(s):  
Farah ‘Atiqah Abdul Azam ◽  
Zakaria Razak ◽  
Mohd Khairul Fadzly Md Radzi ◽  
Norhamidi Muhamad ◽  
Che Hassan Che Haron ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Injection Molding ◽  
Multiwalled Carbon Nanotubes ◽  
Flow Behavior ◽  
Load Factor ◽  
Injection Molding Process ◽  
Green Composite ◽  
Molding Process ◽  
Multiwalled Carbon ◽  
Kenaf Fiber

The incorporation of kenaf fiber fillers into a polymer matrix has been pronounced in the past few decades. In this study, the effect of multiwalled carbon nanotubes (MWCNTs) with a short kenaf fiber (20 mesh) with polypropylene (PP) added was investigated. The melt blending process was performed using an internal mixer to produce polymer composites with different filler contents, while the suitability of this melt composite for the injection molding process was evaluated. Thermogravimetric analysis (TGA) was carried out to investigate the thermal stability of the raw materials. Rheological analyses were conducted by varying the temperature, load factor, and filler content. The results demonstrate a non-Newtonian pseudoplastic behavior in all samples with changed kenaf fillers (10 to 40 wt %) and MWCNT contents (1 to 4 wt %), which confirm the suitability of the feedstock for the injection molding process. The addition of MWCNTs had an immense effect on the viscosity and an enormous reduction in the feedstock flow behavior. The main contribution of this work is the comprehensive observation of the rheological characteristics of newly produced short PP/kenaf composites that were altered after MWCNT additions. This study also presented an adverse effect on the composites containing MWCNTs, indicating a hydrophilic property with improved water absorption stability and the low flammability effect of PP/kenaf/MWCNT composites. This PP/kenaf/MWCNT green composite produced through the injection molding technique has great potential to be used as car components in the automotive industry.

An Analysis of Interfacial Adhesion Between TPU/MWCNT Composites and ABS Substrate by Over Injection Molding

2016 ◽  
Author(s):  
Catalin Fetecau ◽  
Felicia Stan ◽  
Nicoleta Violeta Cristea ◽  
Laurentiu Ionut Sandu
Keyword(s):  
Carbon Nanotubes ◽  
Injection Molding ◽  
Flow Behavior ◽  
Thermoplastic Polyurethane ◽  
Acrylonitrile Butadiene Styrene ◽  
Injection Molding Process ◽  
Molding Process ◽  
Melt Temperature ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

In this work, the advantages of Thermoplastic Polyurethane (TPU) filled with multi-walled carbon nanotubes (MWCNTs) were combined with those of the over injection molding process in order to obtain two-component (2k) structures with very different but high mechanical and electrical properties. TPU/MWCNT composites with different MWCNTs wt.% were over-molded onto Acrylonitrile Butadiene Styrene (ABS) substrates, under different processing conditions, and the adhesion was assessed by T-peel tests at room temperature. Since adhesion is also related to flow behavior, the rheological properties were studied with a capillary rheometer at shear rates similar to those of the injection molding process (102∼104s−1). Experimental results indicated that the most effective way to control the adhesion between the ABS substrate and the over-molded TPU/MWCNT composite is to increase the melt temperature. The addition of carbon nanotubes improves adhesion in the vicinity of 0.5 wt.% MWCNTs.

The Characterization and Flow Behavior of 316L Stainless Steel Feedstock for Micro Metal Injection Molding (μMIM)

2010 ◽  
Vol 44-47 ◽  
pp. 2872-2876
Author(s):  
Pei Li Haw ◽  
Norhamidi Muhamad ◽  
Hadi Murthadha
Keyword(s):  
Stainless Steel ◽  
Injection Molding ◽  
316L Stainless Steel ◽  
Flow Behavior ◽  
Palm Stearin ◽  
Metal Injection Molding ◽  
Injection Molding Process ◽  
Binder System ◽  
Molding Process ◽  
Rheological Characterization

The rheological behaviors of the Micro Metal Injection Molding feedstock are important for the stability of the feedstock during micro injection molding process and quality of the final micro-components. Homogeneous feedstocks are preferable for MIM process to ensure the dimensional consistency of molded components and prevent the defects of powder-binder separation or particle segregation. In this work, feedstocks with various formulations of 316L stainless steel and binder system were prepared by using Brabender Plastograph EC Plus mixer. The binder system comprises of palm stearin, polyethelene (PE) and stearic acid. In order to obtain the viscosity, activation energy, flow behavior and mold ability index, the rheological characterization of the feedstocks were investigated in numerous conditions by using Shimadzu 500-D capillary rheometer The study showed that all of the 316L stainless steel feedstocks are homogenous with pseudo-plastic behaviors.

Study on the Flow Behavior in Thin Cavity during Water-Assisted Injection Molding

2011 ◽  
Vol 467-469 ◽  
pp. 80-83
Author(s):  
Tang Qing Kuang ◽  
Kun Han
Keyword(s):  
Injection Molding ◽  
Control Volume ◽  
Fluid Model ◽  
Flow Behavior ◽  
Experimental Result ◽  
Bulk Temperature ◽  
Injection Molding Process ◽  
Molding Process ◽  
Injection Location ◽  
Good Agreement

A numerical simulation model for the flow behavior of fluids in thin cavity during water assisted injection molding process is built up by adopting general Newtonian fluid model for the filling stage and non-Newtonian and compressible fluid model for the packing stage separately. Finite element/finite difference/control volume methods are adopted for the simulation of melt front, pressure variation at injection location, water thickness fraction and bulk temperature about a plate with trapezoidal cross-section. The simulated melt front location and shape have good agreement with experimental result. In comparison with the simulation results of conventional injection molding, it turns out that water assisted injection molding can obtain parts with low pressure requirement, perfect surface quality and rapid cooling.

scholarly journals Effect of Incorporation of Multiwalled Carbon Nanotubes on the Microstructure and Flow Behavior of Highly Concentrated Emulsions

ACS Omega ◽  
2018 ◽  
Vol 3 (10) ◽  
pp. 13584-13597 ◽  
Author(s):  
Sharu Bhagavathi Kandy ◽  
George P. Simon ◽  
Wenlong Cheng ◽  
Johann Zank ◽  
Kapil Joshi ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Flow Behavior ◽  
Multiwalled Carbon ◽  
Concentrated Emulsions

scholarly journals Uniform Dispersion of Multiwalled Carbon Nanotubes in Copper Matrix Nanocomposites Using Metal Injection Molding Technique

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Ali Samer Muhsan ◽  
Faiz Ahmad ◽  
Norani M. Mohamed ◽  
Puteri Sri Melor Megat Yusoff ◽  
Muhammad Rafi Raza
Keyword(s):  
Carbon Nanotubes ◽  
Injection Molding ◽  
Multiwalled Carbon Nanotubes ◽  
Elevated Temperatures ◽  
Metal Injection Molding ◽  
Ni Catalyst ◽  
Multiwalled Carbon ◽  
Uniform Dispersion ◽  
Pure Cu ◽  
Matrix Nanocomposites

This work presents a novel fabrication approach of multiwalled carbon nanotubes (MWNTs) reinforced copper (Cu) matrix nanocomposites. A combination of nanoscale dispersion of functionalized MWNTs in low viscose media of dissolved paraffin wax under sonication treatment followed by metal injection molding (MIM) technique was adopted. MWNTs contents were varied from 0 to 10 vol.%. Information about the degree of purification and functionalization processes, evidences on the existence of the functional groups, effect of sonication time on the treated MWNTs, and microstructural analysis of the fabricated Cu/MWNTs nanocomposites were determined using TEM, EDX, FESEM, and Raman spectroscopy analysis. The results showed that the impurities of the pristine MWNTs such as Fe, Ni catalyst, and the amorphous carbon have been significantly removed after purification process. Meanwhile, FESEM and TEM observations showed high stability of MWNTs at elevated temperatures and uniform dispersion of MWNTs in Cu matrix at different volume fractions and sintering temperatures (950, 1000 & 1050°C). The experimentally measured thermal conductivities of Cu/MWNTs nanocomposites showed remarkable increase (11.25% higher than sintered pure Cu) with addition of 1 vol.% MWNTs, and slight decrease below the value of sintered Cu at 5 and 10 vol.% MWNTs.

scholarly journals In-mold and Machine Sensing and Feature Extraction for Optimized IC-tray Manufacturing

Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1348 ◽  
Author(s):  
Shih-Chih Nian ◽  
Yung-Chih Fang ◽  
Ming-Shyan Huang
Keyword(s):  
Injection Molding ◽  
Optimal Parameter ◽  
Flow Behavior ◽  
Injection Pressure ◽  
Effective Control ◽  
Injection Molding Process ◽  
Molding Process ◽  
Operator Experience ◽  
Injection Speed ◽  
Screw Position

Injection molding is a mature technology that has been used for decades; factors including processed raw materials, molds and machines, and the processing parameters can cause significant changes in product quality. Traditionally, researchers have attempted to improve injection molding quality by controlling screw position, injection and packing pressures, and mold and barrel temperatures. However, even when high precision control is applied, the geometry of the molded part tends to vary between different shots. Therefore, further research is needed to properly understand the factors affecting the melt in each cycle so that more effective control strategies can be implemented. In the past, injection molding was a “black box”, so when based on statistical experimental methods, computer-aided simulations or operator experience, the setting of ideal process parameters was often time consuming and limited. Using advanced sensing technology, the understanding of the injection molding process is transformed into a “grey box” that reveals the physical information about the flow behavior of the molten resin in the cavity. Using the process parameter setting data provided by the machine, this study developed a scientific method for optimal parameter adjustment, analyzing and interpreting the injection speed, injection pressure, cavity pressure, and the profile of the injection screw position. In addition, the main parameters for each phase are determined separately, including injection speed/pressure during the mold filling phase, velocity-to-pressure switching point, packing pressure and time. In this study, the IC tray was taken as an example. The experimental results show that the method can effectively reduce the warpage of the IC-tray from 0.67 mm to 0.20 mm. In addition, the parameters profiles obtained by parameter optimization can be applied for continuous mass production and process monitoring.

Investigation on the Effect of Carbon Nanotubes Concentration on the Electrical and Rheological Properties of PP/MWCNTs Composites

2015 ◽  
Author(s):  
Felicia Stan ◽  
Laurentiu Sandu ◽  
Catalin Fetecau
Keyword(s):  
Carbon Nanotubes ◽  
Flow Behavior ◽  
Type Equation ◽  
Flow Index ◽  
Injection Molding Process ◽  
Melt Flow ◽  
Molding Process ◽  
Flow Activation Energy ◽  
Multi Wall Carbon Nanotubes ◽  
Injection Molded

The objective of this paper was to investigate the electrical and rheological behaviors of polypropylene (PP) filled with 1.0, 3.0 and 5.0 wt.-% multi-wall carbon nanotubes (MWCNTs). The flow behavior was analyzed in terms of the melt flow index measured at temperatures relevant for the injection molding process and the flow activation energy was calculated using an Arrhenius type equation. The electrical behavior of PP/MWCNTs composites was examined by DC resistance measurements on injection molded samples. The experimental results have shown that the incorporation of MWCNTs effectively enhances the electrical conductivity of the injection molded PP/MWCNTs composites. The composites under analysis can be classified as semi-conductors with the conducting network arranged in 4 dimensions, i.e. the critical exponent of the power-law dependence of the conductivity on the wt.-% MWCNTs is 2.37. The increased conductivity is explained by the orientation of the MWCNTs along the melt flow and the increased nanotubes-to-nanotubes contact after the formation of the percolation network.

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