Rheology of Cellulose Ether Excipients Designed for Hot Melt Extrusion.

A new family of cellulosic ether polymeric excipients has been recently engineered for fabrication of amorphous solid dispersions of active pharmaceutical ingredients via hot-melt extrusion (HME). These hydroxypropyl methyl cellulose excipients enable plasticizer-free melt processing at much lower temperatures (135-160 °C) due to their substantially reduced glass transition temperatures ( T = 98-110 °C). The novel amorphous cellulose ethers were found to be rheologically solidlike well above their glass transition ( T + 70 °C).