K 2013: Enhanced binder system for bioplastics

The Vinnex?  binder system enables polymers based on renewable raw materials to be processed just like conventional thermoplastics. The system enhances the physical properties of bioplastics and makes different materials compatible with each other.

Bioplastics represent promising, sustainable alternatives to petroleum-based products. They are widely manufactured from renewable raw materials and, ideally, are biodegradable. Until now, however, their widespread use was hindered by processing drawbacks compared to conventional thermoplastics. With Wacker’s Vinnex?, a vinyl-acetate-based polymer binder system, manufacturers can now develop high-performance blends of bioplastics. These can be processed with conventional equipment without need for modification. Vinnex?  makes injection molding, extrusion, vacuum forming, thermoforming and calendering much easier.

The binder is compatible with many biopolymers. Different Vinnex? grades can be combined with one or more biopolyesters and fillers in a modular system. Depending on the application, polylactic acid

(PLA), polyhydroxyalkanoates (PHA), polybutylene succinate (PBS) and starch, for example, can be used to create various polymer blends. This significantly improves the physical properties of biopolymers, which are difficult to process otherwise. Depending on the composition and Vinnex?  content, polymer blends have higher impact strengths, are more flexible or have a higher melting strength than onventional biopolymers. The desired properties can thus be adjusted according to the application.

Initial applications tests, for example with PLA, speak for themselves: even though polylactic acid is a very rigid material, extremely thin films of it can easily be produced and also welded more readily with

the help of Vinnex?. The films retain their high transparency after addition of the Wacker  binder. Another plus is that Vinnex?  makes it possible to use combinations of incompatible biopolymers such as PLA and PBS. The compound achieves the advantages of both components. 

Furthermore, Vinnex? enables thermoforming of bioplastics intended for hot filling applications. Thus, the new binder could soon serve as a raw material for coffee cups and soup containers. Wacker already has the necessary food certification of the EU and  of the US Food and Drug Administration (FDA) for selected Vinnex? grades.

Wacker at K 2013 in hall 6, booth A10.