Heat Shrink Film Compound (PLA/PBAT)

About This Product

A pellet compound of polylactic acid and poly(butylene adipate-co-terephthalate) formulated for blown shrink film. The PLA fraction sets the glass transition of the blend and therefore the temperature at which the film responds, while the PBAT fraction keeps the melt extensible enough to be oriented without splitting. Shrink film depends on orientation locked into the film during production and released by heat at the packing line. Drawing the bubble pulls the chains out of their random coils, and the web is cooled below its glass transition before they can relax, so it leaves the line holding stored entropic strain that heat in the tunnel releases as the network recoils toward its unoriented state. The window is narrow at both ends, since too low an onset and the film tightens in a warm trailer, too high and a tunnel cannot deliver the heat at line speed. This compound is formulated so that shrink onset temperature and shrink ratio fall within the window a standard tunnel runs. Shrink behaviour is directional and depends on how the film is produced, so the target shrink figures are agreed against your line and the pack format. Supplied as a raw material for processing on the buyer's own line. We do not produce finished articles. It is used in shrink wrap, in multipack bundling and in pallet and transit wrap. Bio Green Chem supplies the heat shrink film compound to specification on shrink onset temperature, machine and transverse shrink ratio and film gauge.