A new melt-strength enhancer in masterbatch form increases the pull force that can be applied to molten polylactic acid (PLA) by 300% to 500%. This makes possible higher throughputs in PLA extrusion and thermoforming while reducing scrap rates, says Teknor Apex Co., Pawtucket, R.I.
Terraloy MB-90001A1 melt-strength enhancer broadens the processing window of PLA in cast film and sheet for clear products such as clamshell containers. At loading levels of 6% to 10%, the masterbatch dramatically increases the extensional force that can be applied to PLA during processing at drawdown ratios as high as 35:1 (see graph).
“Poor melt strength has limited productivity in processing standard PLA and prevented use of the resin in certain applications,” said Edwin Tam, manager of new strategic initiatives for the Bioplastics Div. of Teknor Apex. “Besides overcoming these obstacles, the new Terraloy masterbatch disperses more efficiently and uniformly in PLA than additives that come in powder form and does not affect the clarity of neat PLA.”