Papers by Keyword: Blend

Abstract: Epoxidized vegetable oils based thermoset materials are widely used to develop biopolymers and to replace the fossil-fuel based polymers. In this paper, a blend of epoxy resin and epoxidized palm oil (EPO) were prepared and characterized by direct and pre-mixed methods to investigate its mechanical properties. For direct method, epoxy and EPO were mixed for 20 minutes at room temperature followed by curing for 2 hours at 100 °C. On other hand, for pre-mixed method, the EPO was reacted with hardener at 120 °C for 1 and 2 hours. Then it was mixed with epoxy resin at room temperature for 20 minutes followed by curing for 2 hours at 100 °C. Fourier transforms infrared spectroscopy [FTIR] and mechanical properties tests were used to characterize the blend. FTIR showed that, a reaction of epoxide group in EPO with active hydrogen atom from hardener and produced a hydroxyl group at 3300 cm^-1. In general, the mechanical properties of epoxy resin/EPO were decreased when the amount of EPO was increased. However, at constant amount of EPO Young’s modulus, toughness, flexural strength, and flexural modulus were slightly increased when the time of EPO/hardener was increased. The mechanical properties were reduced due to the reduction of the cross linking density and effect of plasticizer.

Abstract: Polymer blending is one of the methods used to improve some insufficient properties of conventional polymers. The objective of this work was to study the effectiveness of CR content on the tensile properties and morphology study of recycled polypropylene (rPP)/ chloroprene rubber (CR) blends. The results indicated that the tensile strength and modulus of elasticity of rPP/CR blends decreased, however elongation at break increased as increasing CR content. The morphology study of rPP/CR blends showed the incompatibility between rPP and CR with the detachment of CR particles and CR particles pulled out from rPP surface.

Abstract: PC/ABS is widely used in the vehicle interior, electronic parts and accessories. The study of low cycle fatigue properties have been performed on injection molded samples of PC/ABS blend. The experimental results indicated that the optimum conditions of the fatigue property are melting temperature 200°C, filling time 6 s, and mold temperature 65°C. There has a transition point in the condition of filling time. When the strain amplitude is higher than 0.0118 mm/mm, filling time 6 second has best fatigue properties. By scanning electron microscopy, near the crack initial area, the mechanics of fracture surface are like short and fine fiber. The surface has long fiber ductile fracture, which far away from crack initial area.

Abstract: Polymer blending is a very important and widely used method for the modification of polymer materials. However, little attention has been paid to the Semi-aromatic Polyamides with PPS blends. In this article, we investigate the properties of Poly (phenylene sulfide) (PPS) blends with Poly (hexamethylene terephthalamide/hexamethylene hexanediamide) (nylon 6T/66). The structure, mechanical properties of nylon 6T/66 and (PPS) blends were studied by scanning electron microscopy (SEM), Differential scanning calorimetry (DSC) and Thermogravimetric analysis (TG). The results indicate that the blends have good thermal stability and the tensile strength, flexural strength and flexural modulus of the blends are better than the PA6T/66 but worse than that of the PPS.

Abstract: By blending the different ratio of the low viscosity of bisphenol A type epoxy resin with low viscosity ammonia catalytic phenolic resin, the performance of the resin systems were investigated by the gel time, viscosity, mechanical properties, heat resistance, flame retardance. In addition, DSC was used to detect the thermal property, and FT-IR monitored the reactive process of phenolic-epoxy resin. When the phenolic resin was mixed with 5% epoxy resin, the results were as follow: the gel time of 121 s at 150°C, viscosity of 7760 mPa·s at 30°C, flexural strength of 83.3 MPa, impact strength of 6.9 kJ/m², tensile strength of 20 MPa, heat deflection temperature of 148.5°C, oxygen index of 34.5% and the apparent cure activation energy of 94.2kJ/mol. The resin systems had higher service temperature, low viscosity, excellent mechanical properties and service characteristics, and it could meet the requirements of fast pultrusion process.

Abstract: Non-isothermal crystallization method was performed for pure PLLA and a blend of 50/50 wt% PEO/PLLA samples. The spherulite radial growth rate was calculated and compared to what was acquired using the isothermal crystallization method. It is found that both the fitting order and the decimal number of the fitting polynomial functions heavily affect the resultant spherulite growth rate at different temperatures. It is also important to note that some subtle yet important features might be missed using the quick alternative, such as in the pure PLLA system.

Abstract: The natural rubber/polyvinyl alcohol (NR/PVA) blends containing epoxid natural rubber as the compatilizer were prepared using latex compounding techniques. The mechanical and thermal oxidation aging properties were studied. Mechanical test showed that the tear strength and hardness of the NR were significantly improved due to adding of the PVA. The tensile strength decreased significantly along with the PVA increasing. Thermal oxidation aging test had obviously impact on the mechanical properties of the material. The performance retention of the material properties was taken effect significantly on the aging test.

Abstract: In this paper, a blend of epoxy resin and epoxidized palm oil (EPO) was prepared to investigate its mechanical properties. Epoxy and EPO were mixed for 20 minutes at room temperature before mixed with hardener and followed by curing for 2 hours at 100 °C. Tensile, flexural and impact tests were conducted to characterize the blend. In general, the tensile and flexural properties of epoxy resin/EPO decreased when the amount of EPO increased. However, strain at break, toughness and impact strength was slightly increased when the amount of EPO was increased up to 20%.The mechanical properties were reduced due to the reduction of the cross linking density and effect of plasticizer.

Abstract: Electrospun poly (lactic acid)/poly (lactic acid-co-lysine) (PLA/PLL) blend were prepared, and the structures including fibers, beads and microspheres and properties of electrospun material were characterized. Viscosity, conductivity and surface tension of electrospinning solution had critical effect on the structures of the electrospun blend. The optimization process conditions of PLA/PLL electrospun fibers, beads and microspheres were confirmed and the structures, thermal properties, crystal properties, and hydrophilicity were analyzed. The results showed that the average diameter of electrospun PLA/PLL fibers was less than that of PLA under the same spinning process, and the crystallinity of spun products was affected by solution concentration, pushing speed and spinning voltage. Accurate controlling of spinning product morphology can be achieved by adjusting the formulation of electrospinning solution and spinning process. The addition of PLL into PLA could improve the hydrophilicity of electrospun PLA/PLL products.

Abstract: In an attempt to improve the properties of natural rubber-based medical products, natural rubber (NR) was blended with chitosan (CS) and poly(3-hydroxybutyrate) (PHB) in an laboratory type internal mixer, with the total amount of CS and PHB is of 1, 3, 5, 10, 15 and 20 parts per hundred rubber (phr) , and CS and PHB is of a ratio of 1:1. The testing for processing properties of NR/CS/PHB compounds showed that the Mooney viscosity of NR/CS/PHB compounds increased with the addition of 1.0 phr CS/PHB and then decreased with increase in CS/PHB content, but the Mooney viscosity of each NR/CS/PHB compound was higher than that of NR compound; the minimum torque (M_L) increased only slightly, while the maximum torque (M_H) increased gradually, with increase in NR/CS/PHB content; the scorching tendency of NR/CS/PHB compounds increased with the increase in CS/PHB content; the optimum cure time (t₉₀) decreased firstly, then increased with increase in CS/PHB content, and was not greatly different from that of NR compound. The results of mechanical properties of NR/CS/PHB vulcanizates showed that the tensile strength and elongation at break deceased, whereas the 300% and 500% moduli, tear strength and hardness increased, with increase in CS/PHB content.