Abstract
The dispersion of Mg(OH)2 agglomerates at low concentration in a polymer melt was investigated in a transparent counter-rotating shear cell. The influence of the viscosity of the matrix, the initial agglomerate size and the infiltration of the matrix was evaluated. Mg(OH)2 agglomerates have a low cohesion and a fractal structure. Two dispersive mechanisms already mentioned in the literature were identified: erosion and rupture. Critical conditions for rupture were measured and particle size analysis was performed in order to determine the kinetics of erosion. The infiltration of the matrix, which depends on the viscosity, was found to play a key role on dispersion mechanisms. In contrast to previous works, infiltration is more important with the high viscosity matrix. In infiltrated matrix, rupture was found to occur firstly through plastic deformation of the infiltrated agglomerate, and then the agglomerates split into small fragments. In the low viscosity matrix, fragments produced either by rupture or erosion are small aggregates.
Similar content being viewed by others
References
AstrucM, Collin V, Rusch S, Navard P, Peuvrel-Disdier E (2004) Infiltration of uncured elastomers into silica agglomerates. J Appl Polym Sci 91:3292–3300
Bagster DF, Tomi D (1974) The stresses within a sphere in simple flow fields. Chem Eng Sci 29:1773–1783
Bohin F, Manas-Zloczower I, Feke DL (1994) Penetration of silicone polymers into silica agglomerates and its influence on dispersion mechanism. Rubber Chem Technol 67:602–609
Chen X, Yu J, Guo S (2006) Structure and properties of polypropylene composites filled with magnesium hydroxide. J Appl Polym Sci 102:4943–4951
Collin V, Peuvrel-Disdier E (2005) Dispersion mechanisms of carbon black in an elastomer matrix. Elastomery 9:9–15
Cook M, Harper JF (1998) The influence of magnesium hydroxide morphology on the crystallinity and properties of filled polypropylene. Adv Polym Technol 17:53–62
Dizon ES (1976) Processing in an internal mixer as affected by carbon black properties. Rubber Chem Technol 49:12–27
Hornsby PR (1994) The application of magnesium hydroxide as a fire retardant and smoke-suppressing additive for polymers. Fire Mater 18:269–276
Hornsby PR, Watson CL (1995) Interfacial modification of polypropylene composites filled with magnesium-hydroxide. J Mater Sci 30:5347–5355
Horwatt SW, Manas-Zloczower I, Feke DL (1992) Dispersion behavior of heterogeneous agglomerates at supercritical stresses. Chem Eng Sci 47:1849–1855
Kao SV, Mason SG (1975) Dispersion of particles by shear. Nature 253:619–621
Lee YL, Manas-Zloczower I, Feke DL (1995) Analysis of titanium dioxide agglomerate dispersion in linear low density polyethylene and resulting properties of compounds. Polym Eng Sci 35:1037–1045
Mills SL, Lees GC, Liauw CM, Lynch S (2002) Dispersion assessment of flame retardant filler/polymer systems using a combination of X-ray mapping and multifractal analysis. Polym Test 21:941–948
Mills SL, Lees GC, Liauw CM, Lynch S (2004) An improved method for the dispersion assessment of flame retardant filler/polymer systems based on the multifractal analysis of SEM images. Macromol Mater Eng 289:864–871
Pandya JD, Spielman LA (1982) Floc breakage in agitated suspensions: theory and data processings strategy. J Colloid Interface Sci 90:517–531
Powel RL, Mason SG (1982) Dispersion by laminar flow. AlChE J 28:286–293
Roux C (2008) Caractérisation in-situ des mécanismes de dispersion de la silice dans une matrice élastomère soumise à un cisaillement. PhD Thesis, Ecole Nationale Supérieure des Mines de Paris, MINES-ParisTech, Sophia-Antipolis, France
Rumpf H (1962) Agglomeration, W.A Knepper edn. New York, pp 379–417
Rwei SP, Manas-Zloczower I, Feke DL (1990) Observation of carbon black agglomerate dispersion in simple shear flows. Polym Eng Sci 30:701–706
Rwei SP, Manas-Zloczower I, Feke DL (1991) Characterization of agglomerate dispersion by erosion in simple shear flows. Polym Eng Sci 31:558–562
Seyvet O, Navard P (2000) Collision-induced dispersion of agglomerate suspensions in a shear flow. J Appl Polym Sci 78:1130–1133
Seyvet O, Navard P (2001) In situ study of the dynamics of erosion of carbon black agglomerates. J Appl Polym Sci 80:1627–1629
Suetsugu Y (1990) State of dispersion - Mechanical properties correlation in small particle filled polymer composites. Int Polym Process 5:184–190
Yamada H, Manas-Zloczower I, Feke DL (1998a) The influence of matrix viscosity and interfacial properties on the dispersion kinetics of carbon black agglomerates. Rubber Chem Technol 71:1–16
Yamada H, Manas-Zloczower I, Feke DL (1998b) Observation and analysis of the infiltration of polymer liquids into carbon black agglomerates. Chem Eng Sci 53:1963–1972
Acknowledgements
This work was granted and supported by the Région Rhône-Alpes (France) and by the Nexans Research Center in Lyon (France). Experiments were performed in the CEMEF Centre de Mise en Forme des Matériaux (MINES-ParisTech) in Sophia Antipolis (France).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Olalla, B., Carrot, C., Fulchiron, R. et al. Analysis of the influence of polymer viscosity on the dispersion of magnesium hydroxide in a polyolefin matrix. Rheol Acta 51, 235–247 (2012). https://doi.org/10.1007/s00397-011-0580-z
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00397-011-0580-z