Surface modification and electrostatic charge of polystyrene particles

Particle surface modification by poloxamer adsorption can significantly alt er the electrostatic charge, adhesion behaviour and consequently handling p roperties of a material. The charge reduction on polystyrene spheres achiev ed by this modification technique is dependent on the concentration, molecu lar weight and conformation of poloxamer at the particle surface. Adsorptio n isotherms of poloxamers on polystyrene particles follow a Langmuir profil e and there is an apparent correlation between the extent of adsorption and ability of poloxamer to reduce electrostatic charge. Surface analysis tech niques, X-ray photoelectron spectroscopy and Time of Flight Secondary Ion M ass Spectrometry have generated data on the thickness of the adsorbed polox amer layer and provided evidence to suggest that the polypropylene oxide co mponent of the poloxamer adsorbs to the polystyrene surface and there is a polyethylene oxide rich outer surface which may influence the charge altera tion. (C) 1999 Elsevier Science B.V. All rights reserved.