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Polypropylene Matrix (polypropylene + matrix)
Selected AbstractsThe Dependence between the Process Technologies and the Effect of MAH-PP- Adhesives in Natural Fibre Reinforced Thermoplastic Composites,ADVANCED ENGINEERING MATERIALS, Issue 1-2 2005A. Nechwatal The theoretical possibilities of improving the adhesion between a polypropylene matrix and cellulose natural fibres are well known. However, less is known of how the way of adding MAH-PP products into the composite impacts the adhesion. By comparing mat processes and granule processes this influence on the adhesive effect can be seen. A new process manufacturing natural fibre reinforced granules ( developed in TITK ) was used for these comparisons. It could be shown that the adhesive obviously influences the critical fibre length. [source] Characterization and properties of activated nanosilica/polypropylene composites with coupling agentsPOLYMER COMPOSITES, Issue 11 2009Ong Hui Lin In this work, nanosilica/polypropylene composites containing 1 wt% of silica nanoparticles were prepared by melt mixing in a Thermo Haake internal mixer. Prior compounding, nanosilica was subjected to surface activation using sodium hydroxide (NaOH) solution. The effectiveness of the activation process was evaluated by measuring the amount of hydroxyl groups (OH) on the surface of nanosilica via titration method and supported by FTIR analysis. Two coupling agents namely 3-aminopropyl triethoxysilane (APTES) and neopentyl (diallyl)oxy, tri(dioctyl) phosphate titanate (Lica 12) were used for surface treatment after activation process. The mechanical properties of polypropylene matrix reinforced with silica nanoparticles were determined by tensile and impact test. Hydroxyl groups on the nanosilica surface played an important role in enhancing the treatment with silane coupling agents. To increase the amount of hydroxyl groups on the nanosilica surface, the optimum concentration of NaOH is 1 mol%. Tensile strength, tensile modulus, and impact strength of nanosilica/PP composites improved with activation process. As the coupling agent is concerned, APTES coupling agent is more pronounced in enhancing the mechanical properties of the composites when compared with Lica 12 coupling agent. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers [source] A systematic investigation on the influence of the chemical treatment of natural fibers on the properties of their polymer matrix compositesPOLYMER COMPOSITES, Issue 5 2004Jerico Biagiotti This paper reports a systematic study of the effects on composite properties of different chemical treatments on natural fibers. Both short flax fibers and flax cellulose pulp in a polypropylene matrix have been investigated. The influence of treatments on fiber properties was investigated by means of spectroscopic, thermal and mechanical tests. Moreover, the effects of fiber treatment on the crystallinity of the matrix were analyzed using differential scanning calorimetry and optical microscopy. The mechanical properties of the composites obtained were studied using tensile and bending tests. It is shown that most of the main properties of the composites can be improved by adequately treating the fibers. The results of this study provide a database mainly devoted to material selection for the automotive industry. This research has been performed as a part of the ECOFINA project in the framework of the 5th European Research Program of the European Community. Polym. Compos. 25:470,479, 2004. © 2004 Society of Plastics Engineers. [source] Characterization and design of interphases in glass fiber reinforced polyproplyenePOLYMER COMPOSITES, Issue 3 2000E. Mäder Bond strength between reinforcing fibers and polymer matrices can be controlled in two ways: 1) by intensification of molecular interaction at the interface and 2) by creation of a strong transition layer (interphase) between the components. In this paper, we consider the possibilities of controlling interfacial strength by means of target-oriented variation of structure, thickness and strength of the interphase artificially created between the glass fiber and the polypropylene matrix. The bond strength was measured using a continuously monitored microbond test, including recording the crack length as a function of the load applied. The measured interfacial strengths correlated to the macromechanical properties of glass fiber reinforced polypropylene. The interphase design provided simultaneous increase in the tensile strength and the impact toughness of the composites. [source] Development of a new production method for a polypropylene-clay nanocompositePOLYMER ENGINEERING & SCIENCE, Issue 7 2004Makoto Kato A new production method for polypropylene-clay nanocomposites has been successfully developed. This method did not require the pretreatment of the clay mineral with an organo-cation. In this method we focused our attention on the nature of the clay mineral, which was exfoliated in water. Water was injected into a complex of melted polypropylene and a clay mineral in a twin-screw extruder. By controlling the pressure of the water vapor, the exfoliation of the clay mineral was achieved in the twin-screw extruder. Compatibilizers were added to the mixture of the clay mineral and the polypropylene to prevent aggregation, and we successfully prepared a polypropylene nanocomposite. The silicate layers of the clay mineral in this polypropylene nanocomposite were exfoliated and dispersed uniformly in the polypropylene matrix. This new type of polypropylene nanocomposite had almost the same properties as a conventionally prepared polypropylene-clay nanocomposite. Polym. Eng. Sci. 44:1205,1211, 2004. © 2004 Society of Plastics Engineers. [source] Flame retardancy study on magnesium hydroxide associated with clays of different morphology in polypropylene matrixPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 6 2008B. B. Marosfoi Abstract Fire retardancy behavior of polypropylene,magnesium hydroxide,clay composites of different morphologies is presented. Layer- and needle-like clay nanoparticles in natural and organically surface modified form have been compared. Fire retardant performance of the composites was evaluated by conical combustor and by horizontal burning test, while the structure was characterized by SEM. Rheological analysis of varied temperature provided further information about the strength of the formed combustion residue. The results confirm that fibrous and layered clay nanofillers act synergistically and can be combined with MH microfillers advantageously for improving the flame retardancy of PP composites. Significant improvements were observed in combustion parameters, as well as in flammability classifications. Combination of montmorillonite and sepiolite type of clays resulted in the increased time to ignition, and markedly decreased heat release rate. These advancements are ascribed to the char stabilizer effect of nanofillers leading to increased strength of the residue. It is also concluded that not only the interaction between micro- and nanofillers, but also the nanofillers,nanofillers interaction plays a key role in fire retardant mechanism. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||