CONICET | Buscador de Institutos y Recursos Humanos

&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;!-- /* Font Definitions */@font-face{font-family:Times;panose-1:2 0 5 0 0 0 0 0 0 0;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:12.0pt;mso-bidi-font-size:10.0pt;font-family:"Times New Roman";mso-ascii-font-family:Courier;mso-fareast-font-family:Courier;mso-hansi-font-family:Courier;mso-bidi-font-family:"Times New Roman";}@page Section1{size:612.0pt 792.0pt;margin:72.0pt 90.0pt 72.0pt 90.0pt;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.Section1{page:Section1;} /* List Definitions */@list l0{mso-list-id:295376129;mso-list-type:hybrid;mso-list-template-ids:-1125374638 271469648 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;}@list l0:level1{mso-level-start-at:26;mso-level-tab-stop:36.0pt;mso-level-number-position:left;text-indent:-18.0pt;mso-ansi-font-size:12.0pt;font-family:Times;mso-ansi-font-weight:normal;mso-ansi-font-style:normal;}ol{margin-bottom:0cm;}ul{margin-bottom:0cm;}--&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;E. Krause,M.M. Reboredo, M.I.Aranguren, "Natural Fiber-polypropylene composites madefrom Caranday palm", Journal of Renewable Materials, 4 (2), 101-112, April1st, 2016, http://dx.doi.org/10.7569/JRM.2164.634144&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;!-- /* Font Definitions */@font-face{font-family:Times;panose-1:2 0 5 0 0 0 0 0 0 0;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:3 0 0 0 1 0;}@font-face{font-family:Cambria;panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:10.0pt;margin-left:0cm;mso-pagination:widow-orphan;font-size:12.0pt;font-family:"Times New Roman";mso-ascii-font-family:Times;mso-fareast-font-family:Cambria;mso-hansi-font-family:Times;mso-bidi-font-family:"Times New Roman";}p.MsoNoSpacing, li.MsoNoSpacing, div.MsoNoSpacing{mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:12.0pt;font-family:"Times New Roman";mso-ascii-font-family:Times;mso-fareast-font-family:Cambria;mso-hansi-font-family:Times;mso-bidi-font-family:"Times New Roman";}@page Section1{size:612.0pt 792.0pt;margin:72.0pt 90.0pt 72.0pt 90.0pt;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.Section1{page:Section1;}--&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;Composites made from polypropylene (PP) and local South American fibers traditionally used in yarn derived craftmanshifts, Caranday Palm, were studied regarding the effect of fiber addition, concentration and characteristics of the coupling agent (molecular weight and percentage of grafted maleic anhydride), as well as type of processing. A laboratory scale intensive mixing followed by compression, and pilot plant twin extrusion followed by injection were the two processes investigated. The use of the first one allowed selecting processable formulations with high fiber concentration and a percentage of coupling agentbelow the surface fiber saturation. In fact, it was found that there is a concentration of maleic anhydride moieties that saturates the surface of the fiber irrespective of the agent molecular weight. Increasing the concentration of the coupling agent above that value does not produce further improvement of the mechanical properties. The formulations selected from the results of the laboratory process were considered for the pilot plant (extrusion-injection)process. The use of the second process consisting in extrusion-injection molding showed that the high shear developed in this process leads to defibrillation of the fiber bundles. In the case of the Caranday Palm fibers, this defibrillation resulted in elemental fibers (micron-size) being the effective reinforcement of the composite instead of the technical fibers (millimeter size) that were present in the composites prepared by compression. Better mechanical properties were achieved by using this last method. Key words: Natural fiber composites, defibrillation,injection molding, compression molding, mechanical properties, coupling agents