Attritor-milling of poly(amide imide) suspensions

• Published in: Particuology 2014-12, Vol.17, p.92-96
• Main Authors: Wolff, M.F.H., Antonyuk, S., Heinrich, S., Schneider, G.A.
• Format: Article
• Language: English
• Subjects: Adjustment; Attritor; Decomposition; Differential scanning calorimetry; Glass transition temperature; Grinding; Imides; Particle size; Polymer; Suspension; Thermogravimetric analysis; Tip speed
• ISSN: 1674-2001; 2210-4291
• DOI: 10.1016/j.partic.2013.11.005

•Poly(amide imide) powder was wet-milled in an attritor at various milling conditions.•Polymer powder median diameter was reduced from 21 to 3μm after 7-h milling.•After milling the as-received suspension was stable. The milling behavior of poly(amide imide), which serves as a prototypical hydrophilic high-performance polymer with a high glass transition temperature, was investigated. Various milling conditions (milling times up to 7h, stirrer tip speeds of 3.4–4.9m/s, and mass concentrations of 5–20%) were tested, and particle sizes as low as d50,3∼3μm were obtained. The milling was performed at 11°C in an attritor. Differential scanning calorimetry and thermogravimetric analysis were performed before and after milling to investigate the effect of milling on the glass transition temperature and on the decomposition behavior of the polymer. The suspension obtained after milling was observed to be stable without the addition of stabilizers or the adjustment of the pH value, and no negative effect of milling on the polymer properties was observed. The attritor technique proved to be an adequate and efficient milling tool for the production of micrometer-sized high-performance polymer suspensions.