Thermal and mechanical properties of polypropylene-wood powder composites

• Published in: Journal of applied polymer science Vol. 100; no. 5; pp. 4173 - 4180
• Main Authors: Salemane, M. G., Luyt, A. S.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05-06-2006; Wiley
• Subjects: Applied sciences; Composites; differential scanning calorimetry; Exact sciences and technology; Forms of application and semi-finished materials; gas permeability; Polymer industry, paints, wood; polypropylene; porosity; Technology of polymers; tensile properties; thermogravimetric analysis; wood powder; Particle size; Transport properties; Dispersion reinforced material; polypropylene; Fabrication property relation; Composite material; Thermal stability; wood powder; Olefin polymer; Wood; Propylene polymer; porosity; Mechanical properties; Tensile property; thermogravimetric analysis; Organic anhydride; Crystallinity; Experimental study; Functional polymer; Coupling agent; Thermal properties; Gas permeability; tensile properties; Morphology; differential scanning calorimetry; Fabrication structure relation
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.23521

The preparation and characterization of modified and unmodified polypropylene (PP)–wood powder (WP) composites were done under fixed processing conditions. Different techniques were used to study the effect of both WP size and content, as well as compatibilizer content, on the properties of the composites. The results point to the fact that, WP settles in the amorphous part of the matrix and creates new crystalline phases or zones. Scanning electron microscopy micrographs show a relatively even distribution of WP in the PP matrix, which contributes to improvements observed in the properties of the material. Hg‐porosimetry results indicate that the PP matrix, which has a low pore volume, filled the pores in the WP particles. This reduced the total volume of pores in the PP–WP composites. This observation was also supported by a general decrease in gas permeability of the material. Thermal analysis results indicate that the presence of both WP and maleic anhydride grafted polypropylene (MAPP) leads to an increase in enthalpy (crystallinity) values, but to a decrease in lamellar thickness in the composites. The thermal stability of the composites improves somewhat compared to that of PP. There were distinctive differences between the results for composites containing different WP particle sizes, as well as for composites prepared in the presence and absence of MAPP. It is clear from the results that the presence of MAPP generally improves the tensile properties of the composites. Larger WP particles gave rise to better tensile properties, in the presence and absence of MAPP. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4173–4180, 2006