Physicomechanical behavior of composites of polypropylene, and mineral fillers with different process cycles (original) (raw)
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Effect of the talc filler content on the mechanical properties of polypropylene composites
Journal of Applied Polymer Science, 2008
This research examines the effect of a microsize/nanosize talc filler on the physicochemical and mechanical properties of filled polypropylene (108MF10 and 33MBTU from Saudi Basic Industries Corp. and HE125MO grade from Borealis) composite matrices. A range of mechanical properties were measured [tensile properties, bending properties, fracture toughness, notched impact strength (at the ambient temperature and À20 C), strain at break, and impact strength] along with microhardness testing and thermal stability testing from 40 to 600 C as measured by differential thermal analysis and thermogravimetric analysis. Increasing filler content lead to an increase in the mechanical strength of the composite material with a simultaneous decrease in the fracture toughness. The observed increase in tensile strength ranged from 15 to 25% (the maximum tensile strength at break was found to be 22 MPa). The increase in mechanical strength simultaneously led to a higher brittleness, which was reflected in a decrease in the mean impact strength from the initial 18 kJ/m 2 (for the virgin polypropylene sample) to 14 kJ/m 2 , that is, a 23% decrease. A similar dependency was also obtained for the samples conditioned at À20 C (a decrease of 12.5%). With increasing degree of filling of the talc-polypropylene composite matrix, the thermooxidative stability increased; the highest magnitude was obtained for the 20 wt % sample (decomposition temperature ¼ 482 C, cf. 392 C for the virgin polymer). V
Advances in Science and Technology Research Journal, 2021
The goal is to understand the influence of minerals fillers on the course and performance of process of injection molding polypropylene compounds as well as on the mechanical properties of the obtained products. Three types of mineral fillers, derived from post-production waste, were used for testing. It was aluminosilicate (zeolite), fly ash and gypsum powder, all in powder form. The minerals fillers were introduced into the tested PP in a mechanical mixing process prior to the processing. During the injection molding process, inorganic fillers are subject to the same steps as plastic processing, compression, homogenization, transport. Organic fillers used in the injection process were introduced into the processed PP in the amount of 30% by weight. The test stand consists of a screw injection molding machine, Arburg AllRounder 320C. The research on the structure of manufactured materials, mechanical strength, impact resistance and hardness are presented. The laboratory tests of accelerated aging were conducted using an aging chamber. The aging temperature in the heat chamber was set to even amount of 63 o C and irradiance 0.51 W/m 2. According to the standard, the aging time has been applied accordingly: 120, 240, 360 h, which conform to degradation at room temperature for 4 month, 8 month and one year. It was found that the type of mineral fillers used did not have a significant influence on the hardness of the surface of the moldings. The changes in hardness shown in the figures are primarily influenced by the properties and type of polymers used during the injection process. During the tests, differences in the mechanical strength of composites for injection molded parts made of PP with mineral fillers were observed. Filling PP with zeolite in the tested value causes a decrease in mechanical strength by an average of 10% from 24 to 21.6 MPa. Different mechanical interactions are shown by fly ash and gypsum powder fillers, increasing mechanical resistance of the composition. Fly ash increases mechanical strength by 30% on average, from 24 to 31.2 MPa. In case of gypsum powder application the resistance of PP composition increases analogically, but on average 20%, to 29.5 MPa.
Advances in Condensed Matter Physics
iPP/Talc composites were produced, with different methods of filler addition in iPP matrix. Two different grades of Talc were used for comparison. The tensile tests results showed that talc particles promoted an improvement in composite rigidity, indicating the reinforcing effect of the talc particles in the iPP matrix. However, PP/talc-based composites that were prepared from a masterbatch and with talc grade with smaller particle size showed a better efficiency on dispersion/distribution of particle filler on the thermoplastic matrix, resulting in an improvement in Young’s modulus property, even with higher filler contents. SEM analyses evaluated the composite morphologies and different mathematical models were used as a tool on prediction of mechanical behaviour of the materials. It was observed that the results of Young’s modulus of the composites can be adjusted by different models, depending on the talc characteristics and the mixing procedure used.
Journal of the Chilean Chemical Society, 2014
Inorganic fillers such as CaCO 3 and clays are widely used as fillers to improve the mechanical and physical properties of polypropylene (PP). With the aim of improving simultaneously the stiffness and yield stress of PP, hybrid nanocomposites comprising PP/CaCO 3 /clay (montmorillonite) were prepared and their thermal and mechanical properties were investigated and compared with those of PP/CaCO 3 and PP/clay composites. Morphological characterizations of the composites were performed by SEM and XRD analyses. The results showed exfoliated clay in the hybrid composite with a much higher degree than in PP/ clay composite. Increase in modulus and yield stress and better thermal stability was attained for hybrid composites as a result of the clay exfoliation. The toughening effect of two different types of CaCO 3 particles was also observed in hybrid composites, where an effective enhancement of the mechanical and thermal properties were achieved depending on the origin, specific area, particle and pore size of the CaCO 3 used.
Effect of talc content on the degradation of re-extruded polypropylene/talc composites
Polymer Degradation and Stability, 2013
We have investigated the influence of talc on the rheological, chemical, thermal and mechanical properties of polypropylene (PP)/talc composites (talc content was 0 wt.%, 10 wt.% and 20 wt.%) during multiple re-extrusions. In particular, the materials were extruded and re-extruded after a mechanical grinding of the extrudates for up to six times and then injected to make tensile sample. The main results show the reprocessing of the blends induced thermo-mechanical degradation by chain scission without significant oxidation. Re-extrusion induced a significant decrease of talc particles size and an increase of their aspect ratio. This mechanism caused an increase of rigidity whose intensity increased with the content of talc, and overcame the loss of rigidity due to the thermo-mechanical degradation of PP. The yield stress was stable for PP/talc 80/20 (20 wt.% talc) but increased for PP/talc 90/10 (10 wt.% talc) with the re-extrusion number, while that of neat PP increased for the first re-extrusion and then decreased for higher number of re-extrusions. Therefore, talc has a positive effect on the mechanical properties of PP/ talc composites during re-extrusion.
Journal of Physics: Conf. Series , 2018
This study focuses on improvement of mechanical and physical properties of polypropylene (PP) composite using filler, modifier and jute fiber as reinforcement. Rice husk ash (RHA), low-density polyethylene (LDPE) and jute fiber were used as filler, modifier, and reinforcement in the PP matrix, respectively. A series of test specimens were using various compositions of PP, fillers, modifiers, and reinforcement. Materials were mixed using two roll mixing machine, and specimens were prepared using injection molding machine. The specimens were evaluated on the basis of mechanical (tensile strength, elongation at break) and Physical (water absorption) properties. Effect of RHA was assessed on the basis of mechanical properties. Surface property of the PP composites was studied using Scanning Electron Microscope (SEM). The water absorption property of composites with various compositions was investigated. Further attempts had been made to optimize the three process parameters (RHA, LDPE, jute fiber) in the PP composite with respect to its tensile strength. The optimum parameters for the PP composite were found to be 10 wt% RHA, 10 wt% LDPE and 25 wt% jute reinforcement, respectively in the PP matrix.
The effect of filler types of mica and talc on the oscillatory shear rheological properties, mechanical performance, and morphology of the chemically coupled polypropylene composites is studied in this work. The Maleic Anhydride grafted Polypropylene (MAPP) was used as an adhesion promoter for coupling mineral particles with the polypropylene matrix. The samples were prepared by a co-rotating, L/D¼40, 25mm twin screw extruder. The tensile tests carried out on the injection molded samples showed a reinforcing effect of talc up to 20wt% on the Polypropylene (PP). The tensile strength of PP-mica composites showed a slight decrease at all percentages of mica. The effect of chemical coupling by using MAPP on the tensile strength was more pronounced in increasing the tensile strength for PP-mica than PP-talc composites. The complex viscosity curve of pure PP and the composites, showed a Newtonian plateau (h0) up to 30 wt% at low frequency terminal zone. By increasing the filler content to 40 and 50 wt%, the complex viscosity at very low shear rates sharply increased and showed yield behavior that can be due to the formation of filler particles networks in the melt. At the optimum amount of coupling agent, a minimum in cross over frequency curve against MAPP content is observed. The optimum amount of coupling agent for PP-talc composites is about 1.5%, and about 3% for PP-mica formulations. The analysis of viscosity behavior at power-law high region, revealed the more shear thinning effect of mica than talc on the PP matrix resin
Polymer Bulletin, 2010
The adhesion between the polymer matrix and the inorganic filler particles are the goal of various and tremendous studies. This issue is still occupying a big part of the researchers thinking to find a proper solution, however, its difficulty returns to different factors playing roles in it. Among these factors are the filler surface, i.e., hydrophobicity and hydrophilicity, functional groups on the surface, as well as mineral filler particle size distribution, and particle shape. Therefore, in the current study, the difference in mechanical properties for two mineral fillers; namely, silica and talc, differs in their surface and rheology properties were investigated. Results showed that the difference in the mechanical properties of the same matrix when the inorganic filler is different either in type or loading. Talc showed the better results in terms of Young's modulus and impact strength, where silica showed higher values in terms of yield stress. Moreover, both minerals addition resulted drop in all strain measures, yet silica showed relatively higher measures than talc, but the relative difference measures between the two minerals decrease with increasing their percentage of additions. In brief, the introduction of inorganic fillers to polypropylene (PP) increases toughness, stiffness and strength of the mineral-filled PP end-products.
Polymer Engineering and Science, 2009
Reactive mixing of polypropylene (PP) and talc with epoxy-polyester resin was preformed using a corotating twin screw extruder, and the rheology, morphology, crystallization behavior, and mechanical properties of composites were evaluated. The melts of composites mixed with resin exhibited yield stress and the variation of viscosity against frequency can be approximated in two lines with various slopes. The measurement of the suspension viscosity can be used to characterize the microstructural state of dispersion. Empirical formula was used to relate viscosity with particle concentration, and the analysis showed that the maximum volume fraction increases by using small amount of epoxy resin in the formulations. The morphological study of composites by scanning electron microscopy revealed that the use of resin improved the dispersion of talc in PP, which leads to the arrangement of talc platelets in the direction of flow even close to wall of the mold. The differential scanning calorimetry showed that the epoxy resin suppressed the nucleation effect of talc on PP while the degree and rate of crystallization increased. The compatibilization by maleic anhydride-grafted polypropylene showed a noticeable increase in tensile strength of composites reactively mixed with epoxy resin. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers