Influence of pigment concentration and particle size on adhesion of an acrylic resin copolymer to tablet compacts.
The effects of the particle size and the concentration of pigments in aqueous polymeric dispersions on the adhesive properties of an acrylic resin copolymer were investigated. Aqueous polymeric dispersions containing up to 20% (v/v) pigment were coated onto hydrophilic and hydrophobic tablet compacts, and polymer adhesion was assessed using a novel butt adhesion technique. An inverse relationship was found between the particle size of the pigment present in the aqueous polymeric dispersion and film-tablet adhesion. As the particle size of the pigment increased, the adhesive strength of the polymer to the tablet compact decreased. Increased concentrations of the opacifying agent titanium dioxide in the acrylic dispersion resulted in stronger film-tablet adhesion. No clear relationship could be established between the wettability of the tablet compact by the pigmented polymeric dispersion and the strength of film-tablet adhesion. The hydrophobicity of the tablet compact was found to affect the glass transition temperature of the polymeric film to a greater extent than the particle size, morphology, or concentration of the pigment incorporated into the acrylic dispersion.
Felton
L A
LA
University of New Mexico, Health Sciences Center, College of Pharmacy, Albuquerque 87131, USA.
McGinity
J W
JW
D000180:Acrylic Resins / Q000737:chemistry*; D000268:Adhesiveness; D010316:Particle Size; D010860:Pigments, Biological / Q000494:pharmacology*; D013607:Tablets
D000180:Acrylic Resins; D010860:Pigments, Biological; D013607:Tablets