A technological breakthrough for the development of a new, more innocuous PVDC with enhanced properties – ASAP

Polyvinylidene chloride (PVDC) is widely used in food and drug packaging, due to his excellent water vapor and oxygen barrier properties. PVDC is sold as either an extrudable resin or as an aqueous dispersion (latex) for coating. These applications, and also legislation related to these products, require that the level of degradation products be minimized, and the migration of any additives and/or by-products be well controlled and documented.

This polymer has some limitations: migration of additives, which is a common problem to all industrial polymers synthesized by heterogeneous polymerization, and resistance to storage conditions and certain treatments. Limitations could be reduced if the following identified properties can be improved :

• resistance to UV and visible light,
• resistance to Beta radiation during processing of multilayer films,
• thermal stability of PVDC during extrusion processing,
• thermal stability of coated films, and
• reduction of the migration of by-products and additives.

The ASAP industrial research project aims to understand the degradation mechanisms, identify the various species which can be generated during PVDC degradation, and develop suitable solutions to limit the migration phenomena of both desirable species (such as surfactants and additives) and undesirable species (such as by-products). This understanding requires a preliminary analysis of the co-extruded and coated films produced with PVDC.

Therefore, the proposed research programme will focus on the following points:

• to know the critical UV and visible light wavelengths which contribute to PVDC degradation,
• to know the impact of ? radiation on the PVDC layer in a coextruded film,
• to better understand the relative contributions of both the monomer units used and the end groups present in the PVDC backbone to thermal degradation of PVDC products, and
• to compare latexes using molecular surfactants to latexes without molecular surfactants.

Research project results will lead to the development of a new generation of PVDC. In order to reach that goal, there is a high need for technological breakthrough by working on innovative processes, based on high level studies carried out at academic level, and which have demonstrated real benefits in terms of both polymer properties and processing.

The multidisciplinary team brought together to execute the ASAP project includes renowned industrial and academic parties to ensure improvement of the current state-of-the-art and compliance with future industry (and market) specifications.

SOLVIN SA, as project scientific coordinator, will lead this team with future industrial/market needs in mind. Academic partners UPMC, C2P2, ICG, LCP andTue Eindhoven, will all contribute with specific know-how, knowledge and experience in well defined areas and develop specific competencies.