Processing of wood plastic composites: The influence of feeding method and polymer melt flow rate on particle degradation

Spruce wood particle (WP)/polypropylene (PP) compounds were prepared in an internal mixer using different rotor speeds. To analyze the effect of feeding method on particle degradation, WP and PP were either fed as dry-blend or WP was fed into the PP melt. To prevent melt freezing, pre-heated WP were used as comparison to cold WP. In addition, WPs were compounded with different grades of PP or high-density polyethylene (HDPE) to analyze the effect of polymer matrix melt flow rate (MFR) on particle degradation. Mixing behavior of compounds containing 30% and 70% (w/w) WP depended on feeding method, represented by a changing relation of final torque values. Feeding as dry-blend and using pre-heated particles led to stronger WP degradation. Degradation decreased with increasing polymer MFR. For PP compounds, particle degradation was stronger when containing 70% WP, for HDPE the difference due to WP content was only marginal. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43231.

[1]  S. Bateman,et al.  Wood Fiber Reinforced Polyethylene and Polypropylene Composites with High Modulus and Impact Strength , 2008 .

[2]  A. McDonald,et al.  The effect of micron sized wood fibers in wood plastic composites , 2013 .

[3]  J. Vlachopoulos,et al.  Effects of polymer molecular weight and filler particle size on flow behavior of wood polymer composites , 2008 .

[4]  A. Behravesh,et al.  Experimental investigation on reprocessing of extruded wood flour/HDPE composites , 2012 .

[5]  R. Misra,et al.  Ferrocenyl thiazoles: synthesis and properties , 2015 .

[6]  H. Wolf.  Screw plasticating of discontinuous fiber filled thermoplastic: Mechanisms and prevention of fiber attrition , 1994 .

[7]  M. Wolcott,et al.  Rheology of wood plastics melt. Part 1. Capillary rheometry of HDPE filled with maple , 2005 .

[8]  J. Beaugrand,et al.  Evolution of lignocellulosic fibre lengths along the screw profile during twin screw compounding with polycaprolactone , 2014 .

[9]  K. Yam,et al.  Composites from compounding wood fibers with recycled high density polyethylene , 1990 .

[10]  S. Y. Zhang,et al.  Effects of raw fiber materials, fiber content, and coupling agent content on selected properties of polyethylene/wood fiber composites , 2007 .

[11]  J. Vlachopoulos,et al.  Influence of coupling agents on melt flow behavior of natural fiber composites , 2007 .

[12]  G. Ziegmann,et al.  Effect of extruder elements on fiber dimensions and mechanical properties of bast natural fiber polypropylene composites , 2014 .

[13]  T. Rose,et al.  Dispersion, temperature and torque models for an internal mixer , 2004 .

[14]  H. Schreiber,et al.  Rheological properties of corona modified cellulose/polyethylene composites , 1992 .

[15]  J. Beaugrand,et al.  Lignocellulosic Fiber Reinforced Composites: Influence of Compounding Conditions on Defibrization and Mechanical Properties , 2013 .

[16]  A. Echtermeyer,et al.  Effect of the preparation of cellulose pellets on the dispersion of cellulose fibers into polypropylene matrix during extrusion , 2010 .

[17]  G. Ausias,et al.  Study of the fibre morphology stability in polypropylene-flax composites , 2013 .

[18]  Nicole M. Stark,et al.  Wood fiber derived from scrap pallets used in polypropylene composites , 1999 .

[19]  Craig M. Clemons.  Raw materials for wood-polymer composites. , 2008 .

[20]  John G. Lyons,et al.  The effect of processing conditions for polylactic acid based fibre composites via twin-screw extrusion , 2014 .

[21]  Michael P. Wolcott,et al.  Rheology of HDPE–wood composites. I. Steady state shear and extensional flow , 2004 .

[22]  P. Evon,et al.  Twin-screw extrusion impact on natural fibre morphology and material properties in poly(lactic acid) based biocomposites , 2013 .

[23]  L. Matuana,et al.  Effect of processing method on surface and weathering characteristics of wood–flour/HDPE composites , 2004 .

[24]  R. Rowell.  Challenges in Biomass–Thermoplastic Composites , 2007 .

[25]  G. Dai,et al.  Fiber dispersion and breakage in deep screw channel during processing of long fiber-reinforced polypropylene , 2014, Fibers and Polymers.

[26]  Petri Jetsu,et al.  Wood based PLA and PP composites: Effect of fibre type and matrix polymer on fibre morphology, dispersion and composite properties , 2014 .

[27]  R. Gupta,et al.  Improved wood–plastic composites through better processing , 2008 .

[28]  R. Valette,et al.  Influence of Extrusion Conditions on Fiber Breakage along the Screw Profile during Twin Screw Compounding of Glass Fiber-reinforced PA , 2013 .

[29]  Magnus Bengtsson,et al.  Extrusion and mechanical properties of highly filled cellulose fibre-polypropylene composites , 2007 .

[30]  Y. Mai,et al.  Mechanical properties of wood flake–polyethylene composites. Part I: effects of processing methods and matrix melt flow behaviour , 2001 .