Morphology and mechanical properties of Nylon 6/MWNT nanofibers (original) (raw)
Related papers
Acta Polymerica Sinica, 2007
Phase morphology and mechanical properties of the blends of Nylon 6 with scrap poly(vinyl butyral) (PVB) film and poly[styrene-block-(ethylene-co-butene)block-styrene] (SEBS) have been investigated. Scanning electron microscopic photographs revealed that the spherical PVB particles are finely and uniformly dispersed in the Nylon 6 matrix without changing the shape of the particles. The average particle sizes in all over the blend compositions for Nylon 6/PVB were slightly increased with PVB content, but the dispersed phase is tightly adhered to the matrix phase, with PVB content in the range of 20-35 wt % PVB. Elongation at break and notched Izod impact strength of all the blends were enhanced, which implies good interfacial adhesion. The rubberlike PVB film adhering to the Nylon 6 phase is suggested to give an improved impact strength and toughness. In particular, the optimum PVB content for the best impact strength is found to be in the vicinity of 20-35 wt %, and this composition exhibits better moisture resistance than the other blend compositions. All of the blends up to 35 wt % PVB show higher mechanical properties than those of Nylon 6 blended with conventional impact modifier SEBS. Thus, plasticized PVB film, which is recycled from the process of automobile safety glasses, is applicable as an impact modifier or a toughening agent of Nylon 6.
Polymer, 2000
Toughening mechanisms in blends containing 60 parts nylon 6,6, 20 parts polypropylene (PP) and 20 parts styrene-ethylene/butylenestyrene (SEBS) grafted to different levels of maleic anhydride (MA) were investigated. The sequence of events was carefully characterised using different microscopic techniques. It was found that under triaxial constraint interfacial cavitation followed by multiple crazing and subsequently massive shear yielding of the matrix contributed to an enormous toughening effect in core-shell microstructures observed in 0.92%-maleated blend (0.74% in Part I paper [Wong SC, Mai Y-W. Polymer, 1999;40:1553], should be 0.92% as corrected in this paper). The core-shell structure was formed when the spherical domains of PP were surrounded by SEBS rubber in a nylon-rich matrix.. In this composition, miscibility between the dispersed SEBS-g-MA and the nylon phase was maximised as revealed by thermal-mechanical analysis. The SEBS was most effective in toughening the nylon/PP blends when it cavitated to introduce ligament bridges between debonded PP particles at the crack tip. Interfacial cavitation and multiple crazing served to relieve the hydrostatic tension ahead of crack growth and subsequently enhanced the shear-yielding component of stresses in the matrix material. Other blend compositions that did not show controlled cavitation resulted in little plastic flow surrounding the crack tip and reduced fracture toughness. These results reinforced the notion that cavitation of SEBS at the nylon-PP interface was an essential mechanism to promote toughening in materials subjected to high crack tip triaxiality.
Polymer, 2000
The impact fracture parameters of blends of nylon 6 and maleated ethylene±propylene rubber (EPR-g-MA) reinforced with glass ®bers as a function of glass ®ber and EPR-g-MA content were examined. Both the linear elastic fracture mechanics (LEFM) model and a modi®ed essential work of fracture (EWF) model were used to analyze the data. It was found that the addition of EPR-g-MA to unreinforced nylon 6 increased the EWF parameters u o and u d de®ned by U=A u o 1 u d`; where U/A is the total fracture energy per unit area and l is the ligament length. Beyond a critical rubber content, which coincided with the ductile-to-brittle transition, there was a large increase in u d. When glass ®ber reinforcement was used without rubber toughening, the EWF model was unable to model the observed fracture response. On the other hand, the LEFM model adequately described the fracture behavior, and it was found that the critical strain energy release rate, G IC , increased with increasing glass ®ber content. When both glass ®ber reinforcement and rubber toughening were used, the u o increased with increasing EPR-g-MA or glass ®ber content; whereas, u d increased with increasing ERR-g-MA content or decreasing glass ®ber content.
Studies on Mechanical Properties of ABS-NYLON 66 POLYBLENDS
Polymer blends are capable of providing materials which extend the useful properties beyond the range that can be obtained from single polymer equivalents. Blends of Acrylonitrile-Butadiene-Styrene (ABS) and Nylon 66 were prepared in different ratios in presence of styrene-meleic anhydride copolymer as a compatibilizer by melt blending technique which was carried out using an extruder which was followed by injection moulding process. Nylon 66 at different weight ratios was incorporated into the blends to study the effects of blend ratio on the properties of the blend. This study focused upon tensile, flexural, and impact properties of ABS-Nylon 66 polymer blends.
The Mechanical Properties of Nylon 6 (PA6)/ACRYLONITRILE-BUTADIENE-STYRENE (Abs) Blends
2006
Blending is a combination of two or more polymer to produce a new polymer which has good mechanical properties at low cost. Nylon 6 and ABS both have their specialty and weakness but on the other hand, with the combination of Nylon/ABS, it helps to patch both weaknesses. For this study, high impact ABS was used to blend with PA 6 to improve the mechanical properties and to reduce the cost. The main purpose of this study was to investigate the ratio of PA 6/ABS blends to produce a good combination of mechanical properties such as tensile, flexural and impact properties. Besides, the study was also investigate the compatibility of PA 6/ABS and to examine the structure morphology of its blends. For sample preparation, the pellets of PA 6 and ABS were extruded at the different composition using twin screw extruder and then being moulded using injection moulding machine. In this study, the tests conducted were tensile test, flexural test, Izod impact test and morphology examination of PA 6/ABS blends. With the increasing of ABS content in PA 6/ABS blend, the tensile strength, tensile modulus and elongation at break were decreased. Besides, the flexural strength and flexural modulus of the blend were also decreased. However, the addition of ABS increased the Izod impact strength of the blend. The best ratio for the PA 6/ABS blends based on the mechanical properties is 60:40 PA 6/ABS.
Effect of Particle Size of Filler on Properties of Nylon-6
Journal of Minerals and Materials Characterization and Engineering, 2004
Particulate reinforced thermoplastic composites are designed to improve the properties and to lower the overall cost of engineering plastics. In this study the effects of adding mica with variable particle size on the mechanical, thermal, electrical and rheological properties of nylon-6 was investigated. Composites of nylon-6 with v arying concentrations (viz. 5 to 40 weights %) of mica were prepared by twin screw extrusion. The composite showed improved mechanical, thermal as well electrical properties on addition of filler. It is also observed that mechanical properties, electrical properties as well as thermal properties increases with decrease in particle size.
Polymer, 2001
The impact fracture parameters of blends of nylon 6 and maleated ethylene±propylene rubber (EPR-g-MA) reinforced with glass ®bers as a function of glass ®ber and EPR-g-MA content were examined. Both the linear elastic fracture mechanics (LEFM) model and a modi®ed essential work of fracture (EWF) model were used to analyze the data. It was found that the addition of EPR-g-MA to unreinforced nylon 6 increased the EWF parameters u o and u d de®ned by U=A u o 1 u d`; where U/A is the total fracture energy per unit area and l is the ligament length. Beyond a critical rubber content, which coincided with the ductile-to-brittle transition, there was a large increase in u d. When glass ®ber reinforcement was used without rubber toughening, the EWF model was unable to model the observed fracture response. On the other hand, the LEFM model adequately described the fracture behavior, and it was found that the critical strain energy release rate, G IC , increased with increasing glass ®ber content. When both glass ®ber reinforcement and rubber toughening were used, the u o increased with increasing EPR-g-MA or glass ®ber content; whereas, u d increased with increasing ERR-g-MA content or decreasing glass ®ber content.
Morphology and properties of nylon 6-polyoxypropylene-nylon 6 block copolymers
Materials Chemistry and Physics, 1994
The morphology and mechanical properties of nylon 6-polyoxypropylene (POP)-nylon 6 block copolymers as functions of POP content were studied using infrared spectrophotometry, electron microscopy, X-ray diffraction, reheometric measurement and impact testing. The copolymers exhibit a unique morphology having spherulites with feather-like texture, containing POP-rich amorphous domains; the texture varies with POP content. The spherulite is presumed to consist of lamellae, nylon-rich amorphous domains between lamellae and POP-rich amorphous domains outside the interlamellar region. The crystal structure of the copolymers is mainly a-form with a relative shift of hydrogen-bonded sheets in the crystal unit cell. In the dynamic damping spectra, multiple transitions appear in the a-transition range of nylon 6. One is due to the conventional transition of nylon segments, another is due to POP-hydrogen bonded nylon segments. The impact strength is better than that of pure nylon 6 and increases with decrease of POP content. The area of indent zones in the fractured surface change in the same manner as the change of impact strength and POP domain size with POP content. The size and distribution of the POP-rich domains in the spherulites is suggested to be a governing factor for the morphology and properties of the nylon block copolymers.
Polymer, 1986
Ternary polyamide-based blends have been prepared by adding to nylon-6 (PA6) an ethylene-propylene random copolymer (EPM) and the same EPM functionalized by inserting onto its backbone maleic anhydride groups (EPM-g-SA). Two kinds of processing have been used: (a) one-step mixing in which the three components were simultaneously introduced in the mixer; (b) two-step mixing in which the two rubbers EPM and EPM-g-SA were separately premixed before the f'mal mixing with PA6. Also binary PA6/EPM-g-SA blends have been prepared to compare their properties with those of the ternary one. Mechanical tensile characterization at room temperature and impact Izod tests at different temperatures as well as a morphological analysis of smoothed samples have been performed on all the blends. It has been shown by a model reaction that both in binary and ternary blends an EPM-g-PA6 graft copolymer is formed, which acts as an interfacial agent between the rubbery dispersed phase and the polyamide matrix. The blends obtained by the one-step mixing showed a gross morphology and a very poor impact resistance, whereas the ones prepared by the two-step mixing exhibited very fine morphologies and excellent impact performances. In addition, as shown at least in the case of one ternary blend, there seems to be good morphological stability of these materials after a second processing. This has been attributed to the influence of the interfacial agent formed during the melt mixing of the two premixed rubbers with PA6.