Izod Impact Strength Of Composites Research Articles

Effect of micro‐sized luffa cylindrica fibers on the mechanical properties of epoxy epikote 828

AbstractMicro‐sized luffa cylindrica fibers (MLCFs) are made from raw luffa natural fibers from Vietnam and are environmentally friendly while possessing good mechanical strength. This work focuses on the mechanical properties of composite based on epoxy epikote 828 reinforced with MLCFs, particularly the fracture toughness. The results show that the MLCFs content has a great influence on the fracture toughness, especially the critical‐stress intensity factor (KIC) and izod impact strength of composite. Specifically, when using MLCFs reinforced from 0 to 2.0 wt.%, the critical‐stress intensity (KIC) increased from 1.89 to 4.60 MPa.m1/2, while the izod impact strength increased from 3.6 to 7 KJ/m2, respectively. The thermal behavior of the composite reinforced with MLCFs at different contents was determined using thermogravimetric analysis (TGA). The surface fracture structure of the composite samples was determined using scanning electron microscopy (SEM) method.

MECHANICAL AND PHYSICAL PROPERTIES OF WOOD/POLYETHYLENE COMPOSITE REINFORCED WITH TIO2 NANOPARTICLES

Wood plastic composite was fabricated using high density polyethylene and pine wood fiber. The effect of addition of TiO2 nanoparticles at different weight fractions (0%, 1%, 3%, and 5%) on some properties of the composite was examined. The experimental composites were tested for bending strength, tensile strength, Izod impact strength, thickness swelling, and contact angle. Field emission scanning electron microscopy was also investigated to study the distribution of TiO2 nanoparticles in the composites. The results showed that using TiO2 nanoparticles as a reinforcing agent in wood plastic composites resulted in an increase in the tensile and bending strengths and a decrease the thickness swelling of the composites. The effect of TiO2 nanoparticles on the Izod impact strength of composites was not significant. The results also showed that the contact angle of wood plastic composites was improved by using TiO2 nanoparticles.

Mechanical Properties of Microcrystalline Cellulose (MCC) Filled Engineering Thermoplastic Composites

In this study, engineering thermoplastic composites were prepared from microcrystalline cellulose (MCC)-filled nylon 6. MCC were added to nylon 6 using melt mixing to produce compounded pellets. The MCC-filled nylon 6 composites with varying concentrations of MCC (from 2.5 to 30 wt%) were prepared by injection molding. The tensile and flexural properties of the nylon 6 composites were increased significantly with the addition of MCC. The maximum strength and modulus of elasticity for the nylon 6 composites were achieved at a MCC weight fraction of 20 %. The Izod impact strength of composites decreased with the incorporation of MCC without any surface treatments and coupling agent. This observation is quite expected for filled polymer systems and has been commonly observed. There was a strong correlation between density and tensile (r = 0.94) and flexural modulus of elasticity (r = 0.9). MCC filled composites manufactured by injection method had highly uniform density distribution through their thickness. The higher mechanical results with lower density demonstrate that MCC can be used as a sufficient reinforcing material for low cost, eco-friendly composites in the automotive industry especially for under-the-hood applications (engine covers, intake manifolds and radiator end tanks) as well as in other applications such as the building and construction industries, packaging, consumer products etc.

Short carbon fiber reinforced polycarbonate composites: Effects of different sizing materials

In this paper, effects of the sizing material type and level on the mechanical, electrical and morphological properties of the short carbon fiber (CF) reinforced polycarbonate (PC) composites were investigated. Unsized CF and the CFs which were sized with epoxy/phenoxy(EPO_PHE), polyimide(PI) and phenoxy(PHE) were used as reinforcement materials. Fiber length distribution analysis indicated that sizing protected the CFs breakage into the smaller lengths during the processing. Effects of the sizing material type and level on the mechanical properties of CF reinforced PC composites were investigated by means of tensile and izod impact strength tests. Tensile test results revealed that tensile strength and modulus values of sized CF reinforced PC composites were higher than that of unsized CF reinforced PC composites. Besides, effect of the sizing material level on the tensile properties of composites changed with respect to the sizing material type. It was also found that the measured effects of the sizing agent type and level on the notched izod impact strength of composites were not so significant. In addition to this, it was found that sized CF reinforced PC composites had higher electrical conductivity values than unsized CF reinforced PC composites. Also, PHE sized CF reinforced composites had the highest electrical conductivity value among the other composites. Better interactions between EPO_PHE and PHE sized CF and PC matrix were observed from the scanning electron microscope analysis. As a result of this study, PHE and EPO_PHE sized CFs can be suggested as proper reinforcements for PC matrix.

Natural fiber blend—nylon 6 composites

AbstractIn this study, engineering thermoplastic composites were prepared from natural fiber blend–filled nylon 6. Natural fiber blend from a mixture of kenaf, flax, and hemp fibers were added to nylon 6 using melt mixing to produce compounded pellets. The natural fibers/ nylon6 composites with varying concentrations of natural fibers (from 5 to 20 wt%) were prepared by injection molding. The tensile and flexural properties of the nylon 6 composites were increased significantly with the addition of the natural fiber blend. The maximum strength and modulus of elasticity for the nylon 6 composites were achieved at a natural fiber blend weight fraction of 20%. The Izod impact strength of composites decreased with the incorporation of natural fibers without any surface treatments and coupling agent. The melt flow index (MFI) also decreased with increasing natural fiber blend loading. The results of tensile and flexural modulus of elasticity (FMOE) are in accordance with the rheological data from the MFI measurements. The increase in the tensile and flexural properties indicated that efficient bonding occurred between the natural fibers and nylon 6. No fiber pullout was observed during the scanning electron microscopic analysis of the fracture surfaces. The higher mechanical results with lower density demonstrate that a natural fiber blend can be used as a sufficient reinforcing material for low‐cost, eco‐friendly composites in the automotive industry and in other applications such as the building and construction industries, packaging, consumer products, etc.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers

Effect of surface modifiers and surface modification methods on properties of acrylonitrile–butadiene–styrene/poly(methyl methacrylate)/nano‐calcium carbonate composites

AbstractNano‐calcium carbonate (nano‐CaCO3) was used in this article to fill acrylonitrile–butadiene–styrene (ABS)/poly(methyl methacrylate) (PMMA), which is often used in rapid heat cycle molding process (RHCM). To achieve better adhesion between nano‐CaCO3 and ABS/PMMA, nano‐CaCO3 particles were modified by using titanate coupling agent, aluminum–titanium compound coupling agent, and stearic acid. Dry and solution methods were both utilized in the surface modification process. ABS/PMMA/nano‐CaCO3 composites were prepared in a corotating twin screw extruder. Influence of surface modifiers and surface modification methods on mechanical and flow properties of composites was analyzed. The results showed that collaborative use of aluminum–titanium compound coupling agent and stearic acid for nano‐CaCO3 surface modification is optimal in ABS/PMMA/nano‐CaCO3 composites. Coupling agent can increase the melt flow index (MFI) and tensile yield strength of ABS/PMMA/nano‐CaCO3 composites. The Izod impact strength of composites increases with the addition of titanate coupling agent up to 1 wt %, thereafter the Izod impact strength shows a decrease. The interfacial adhesion between nano‐CaCO3 and ABS/PMMA is stronger by using solution method. But the dispersion uniformity of nano‐CaCO3 modified by solution method is worse. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013