Disclosed are polyester shrink films comprising a voiding agent dispersed
within a continuous polyester phase. The voiding agent comprises at least
one first polymer and at least one second polymer, in which the polymer
components have selected physical properties such as glass transition
temperature, melting point, tensile modulus, surface tension, and melt
viscosity. The resulting shrink films have high opacity, a low
coefficient of friction, lower density, low shrink force, and good
printability. The films are useful for sleeve label and other shrink film
applications, and their lower density allows them to be readily separated
from soft drink bottles, food containers and the like during recycling
operations. Also disclosed is a process for separating a void-containing
polyester from a mixture of polymers.
