G. Gorrasi et al., TRANSPORT-PROPERTIES OF POLY(ETHYLENE-TEREPHTHALATE) RODRUN-3000 BLENDS, Journal of macromolecular science. Physics, 36(5), 1997, pp. 643-653
The transport properties of incompatible blends of poly(ethylene terep
hthalate) (PET) and a thermotropic liquid crystalline polymer (TLCP) c
omposed of 40 mol% of PET and 60 mol% of p-hydroxybenzoic acid (Rodrun
3000) have been investigated using dichloromethane as permeant. Films
, obtained by a blown film extrusion process, were analyzed and compar
ed with the same samples stored 2 and 15 days at 60 degrees C. With re
spect to the as-blown films, blends submitted to physical aging show a
decrease in permeability by a percentage that increases with the amou
nt of the LC phase present and a larger contribution derived from the
polymeric matrix. The decrease of permeability is essentially attribut
ed to a lowering of sorption because diffusional behavior for the diff
erent samples is the same.