Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7825510 | Polymer Testing | 2018 | 7 Pages |
Abstract
Polymeric materials absorb water when exposed to humidity or in contact with aqueous solutions. The polymer and water molecules interact, changing the physicochemical parameters of the material; the most noticeable effect is a decreased glass transition temperature (Tg), known as plasticization. We used microcantilever sensors to measure the Tg versus moisture content in poly(lactic-co-glycolic acid) (PLGA), a biodegradable polymer used in implants and as a drug carrier. We demonstrate a concomitant measurement of the mass absorption and Tg using nanograms of material and an inexpensive setup. The standard deviation of Tg for this system was 0.025â¯Â°C, and the variation in Tg with respect to a 1% RH change was clearly resolved. The decrease in the Tg of PLGA was linear (R2â¯=â¯0.99) at a rate of 6.03â¯Â±â¯0.57â¯Â°C per mass% of water absorbed. The initial dry Tg of PLGA was extrapolated to 41.24â¯Â±â¯0.07â¯Â°C.
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Gustavo Marcati A. Alves, Sanjukta Bose Goswami, Ronaldo D. Mansano, Anja Boisen,