Compression of thermally treated Polyethylene glycol 10,000

The effect of cooling rate on compression properties of melted Polyethylene glycol (PEG) 10,000 has been evaluated. The mean yield pressures, gross and plastic energies have been investigated using a compaction simulator. Tensile strengths, tablet deformation and work of failure of the tablets were determined using a JJ Lloyd compression testing machine. The increase in compression speed increases the mean yield pressure and decreases the tensile strength. Slow cooled sample is the most crystalline and exhibit higher compressibility and produce stronger tablets than untreated and quench cooled samples at all compression speeds. The untreated sample has intermediate crystallinity and shows more resistance to densification and produces tablets of low strength. Quench cooled is the least crystalline but shows better compressibility and give harder tablets in comparison with untreated sample. The study highlights the difficulty in obtaining relationships between crystallinity and compressibility, because particle shape and surface rugosity differ from one sample to another. However a good correlation is observed between the plasticity of PEG and the work of failure. Slow cooled PEG is therefore the most compressible and produces tough tablets which undergo greater deformation before failure. Untreated PEG however, shows less plasticity and produces tablets of low toughness.