A particle rearrangement index based on the Kawakita powder compression equation

• In this article, the effect of original particle size on the Kawakita parameters, denoted a and b, has been studied using four model materials of different compression mechanics. It was found that fine powders, possibly showing significant particle rearrangement at low compression pressures, showed low values of parameter b(-1) and high values of parameter a. It is thus proposed that the product of these parameters is an indication of the overall contribution of particle rearrangement to the compression profile. Above a critical original particle size of a powder, particle rearrangement is negligible for the overall compression profile and below this critical particle size, particle rearrangement becomes significant. A critical particle size of about 40 microm was obtained. A classification of powders into groups dependent on the incidence of particle rearrangement is discussed and it is suggested that a rearrangement index and a classification system could be used as tools to enable rational interpretations of global compression parameters.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Farmaceutiska vetenskaper (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Pharmaceutical Sciences (hsv//eng)

Keyword

Powder compression

Kawakita parameters

particle rearrangement

rearrangement index

powder compression classification system

PHARMACY

FARMACI

Publication and Content Type

ref (subject category)

art (subject category)