Papers by Keyword: Polypropylene (PP)

Abstract: In the present study, the series of PP/SiC composites, containing 5, 10, 15, 20 and 30 wt% of waste SiC particles from abrasive industry, were prepared in order to obtain composites with superior mechanical properties. PP/SiC composites with appropriate amount of SiC were used in order to study the effect of polypropylene-grafted-maleic anhydride (PP-g-MA) as a compatibilizer. PP-g-MA loadings of 0, 1, 3, 5, 7, and 10 wt% were filled composites material by using a two roll mill, extruder and shaped in a hydraulic compression molding machine. Mechanical

Abstract: PS/PP/nano-TiO₂ composites are prepared via melt compounding method. We study on the effects of mechanical properties, rheological, heat stability and microscopic structures on the composites. Results show that the impact resistance performance, compatibility, melt index, etc are associated with the addition amount of TiO₂.

Abstract: Based on the mechanism of processing and molding of multivariate polypropylene composite system, this paper studies the effect of the screw length-to-diameter ratio and the wedge angle of the helix angle of the twin-screw extruder on the properties of elongation at break of polypropylene composite. The relationship between injection temperature and injection pressure of injection molding machine is also analyzed. Experiments show that when length-to-diameter ratio is 30, and wedge angle is 16±5^o, the elongation at break of test sample reaches its maximum value and tends to be stable. When melting pressure is 40 MPa and the injection temperature at 190 °C-220 °C, injection molding machine can improve the process flowing property of composite materials.

Abstract: PP/PA6/APP/OMMT Nanocomposites were Prepared via One-Step and Two-Step Melt Intercalation. the Flame Retardation, Thermostability, Structure Characters and Hygrothermal Aging Properties of PP/PA6/APP/OMMT Nanocomposites were Studied by UL-94, OI, TG and TEM. the Results Show that Two-Step can Improve the Flame Retardation of PP/PA6/APP/OMMT Nanocomposites; when OMMT Content is 4% or 6%, the Flame Retardation Gets Tofv-0, and the Lois are 32.2% and 32.8% Respectively; OMMT Doesn’t Play an Obvious Role to Hygrothermal Aging of PP/PA6/APP/OMMT Nanocomposites.

Abstract: The effects of brominated flame retardant which composed of decabromodiphenyl ethane (DBDPE) and antimonous oxide (AO) on long glass fiber reinforced polypropylene (LGFPP) were investigated by means of limiting oxygen index (LOI), vertical burning (UL-94), thermogravimetry analysis (TGA), and mechanical properties. With the increase of DBDPE-AO content, the LOI values of DBDPE-AO/LGFPP composites increased from 21 to 27.6, and when the content of DBDPE-AO was 16wt%, the composites passed the V-0 rating in UL-94 testing. The experimental results showed that the brominated flame retardant improved flame retardancy of LGFPP, which was proved by the TGA testing. Whats more, the mechanical properties of composites even improved compared with pure LGFPP.

Abstract: The influence of long glass fiber (LGF) content on properties of PVC/PP composites were investigated by means of scanning electron microscopy (SEM), dynamic mechanical analysis (DMA), and mechanical properties. The experimental results demonstrate that long glass fiber could effectively improve the mechanical properties and storage modulus of PVC/PP. The DMA reveals good miscibility between PVC and PP. Based on SEM, good interfacial adhesion between matrix and long glass fiber in PVC/PP/LGF composites was observed. All results in this paper were consistent, and showed long glass fiber could effective influence the properties of PVC/PP, which were proved by the mechanical properties of the composites.

Abstract: This research was conducted to evaluate the strength and folding performance of polypropylene packaging samples, when exposed to hot air and high humidity condition. Three types of polypropylene samples were chosen, which were flat plastic, plastic with hinges, and plastic film. All of these samples were tested for tensile strength; except plastic with hinges that received additional test to evaluate the folding endurance. American Society for Testing and Materials (ASTM) D638 standard was applied to analyze the mechanical strength of these plastics. This standard was used to determine the value of stress, strain, and Young’s modulus. Each sample was exposed to different temperature settings, which were 20°C, 25°C, and 30°C for high humidity condition and 60°C, 65°C, and 70°C for hot air condition. As for the folding endurance test, the hot air temperatures were selected at 60°C, 65°C and 70°C and for the high humidity condition, the range of relative humidity were set at 50%, 55% and 60%. Based on the tensile test results, the values of stress and Young’s modulus were higher at higher humidity as compared with the values under hot air condition. However the strain value was the opposite of the stress and Young’s modulus, whereby the values started to deceive under high humidity condition, but kept on increasing under hot air condition. In folding endurance test, it was confirmed that the hinge performed better under hot air environment than high humidity. As the relative humidity increases, the average number of folding decreased from 3.00x10⁶ to 2.89x10⁶ cycles. In the other hand, thevalue of folding numbers increased from 3.34x10⁶ to 3.37x10⁶, with increasing temperature. In conclusion, through this performance analysis, the outcomes can be applied to other packaging materials and appliances, which are related to high temperature and high humidity condition.

Abstract: The purpose of this study is to evaluate the mould, which is made from mild steel and aluminium, and the effect of these moulds properties towards the quality of thermoplastics part. As for this research, two different types of mould material were fabricated by using Computer Numerical Controller (CNC) milling machine. These moulds were specifically design to produce a test sample which was an integral hinge made from Polypropylene. These moulds were tested practically by using Nissei-NP7-1F injection moulding unit. A set of parameter setting consisting of melt temperature, packaging pressure, injection time, packing time and mould temperature had been chosen to acquire the correlation between the mould materials and the part’s quality. Five tested samples were prepared for evaluation in terms of the material consumption, warpage, and shrinkage values. Results have been observed and analysed and it was found that in term of material consumption value, aluminium mould consumed 1.28 gram or 14% more polypropylene than mild steel. For warpage value, mild steel mould had the lowest value with only 0.08mm warpage. The third experiment showed that the lowest shrinkage was happened to be 0.01302, which was produced by mild steel mould. As the conclusion in this project, mild steel mould was selected as the desirable mould for producing integral hinges samples as compare with the aluminium mould.

Abstract: Nanocomposites based on polypropylene (PP), polyamide 66 (nylon 66) and PP/nylon 66 immiscible blends containing 5wt% TiO₂ nanoparticles were prepared via melt compounding. The influences of TiO₂ on the rheology of nanocomposites and blend nanocomposites were investigated. Scanning electron microscopy results revealed the size of inclusion phase was smaller in PP/PA 66/TiO₂ 75/25/5 comparing to the PP/PA 66/TiO₂ 25/75/5. A co-continuos phase was observed at 50/50 composition. Melt dynamic rheology showed that the moduli of the PP increased with incorporation of TiO₂ nanoparticles at the moderate frequencies, while this effect was reverse in PA 66 nanocomposite. Several rheological and rheo-morphological models were used for prediction of rheological parameters. The well-known models for rheology of suspensions proposed by Einstein, Roscope and Eilers-van Dijck were successful for prediction of viscosity of PA nanocomposite. Palierne model was fitted to the experimental values especially for the: PP/PA 66/ TiO₂ 25/75/5 blend nanocomposite.

Abstract: As a kind of general-purpose plastic, PP possesses a good mechanical property and excellent resistance to chemical attack. So, now, it is widely used. In this article, a kind of decorating materials used in automobile and rubber powders were used to undertake a modification of PP. Besides, mechanical property was tested and SEM,TMA,TG technology were used to investigate some of the property of composites. We drew a conclusion that the composite with a ternary system consists of PP,POE and rubber powder got the best integrated performance.