Vinyl alcohol-based thermoplastics are injection mouldable and extrudable while retaining water solubility and biodegradability. The uses and potential of being able to injection mould PVOH are again governed by PVOHs many unique properties.
The dissipative, nontoxic and water-soluble properties of PVOH, for example, allow PVOH to be used for the manufacture of pharmaceutical capsules. This provides an alternative to gelatine capsules that can have issues relating to static during manufacture. It also provides improved controlled release of active ingredients and a capsule that cannot be easily altered, offering greater protection to malicious tampering.
The innovation in recent moulding processes opens up the possibilities for complex, multi- treatments and staged release capsules. Such uses are possible, because unlike more conventional polymers, PVOH is suitable for human ingestion in food and ingestion by the Federal Drug Association. The veterinary industry also uses PVOH technology to develop fast-acting, anti-worming treatments where novel single-use delivery systems are used.
The unique mouldable and extrudable properties of PVOH could, for example, be used for novel controlled release of aroma therapy formulations. This could be achieved via the wall thickness of the moulding, which could be designed to dissolve over a set time, releasing the active ingredient of the treatment.
The potential of utilising moulded parts made from PVOH is in its infancy and limited only by ones imagination. For instance, the biodegradable properties of PVOH could provide a more environmentally responsible alternative to plastic and board shotgun cartridges and wads, which would provide a more environmentally responsible solution. In this scenario, the discarded case and wad could simply be allowed to biodegrade naturally.
Since PVOH is both mouldable and extrudable it is possible to imagine combining injection moulded components with thermoformed cavities, creating endless possibilities in the medical and pharmaceutical industry.