While remaining decisively behind expectations, the results obtained in the project allowed to clarify the following points:
a) Commercial promises and published results on PP-based organoclay nanocomposites are frequently "very optimistic" and hardly reproducible (results of extensive benchmark testing)
b) Screw design and process optimisation, including the use of new element types, can improve material properties significantly at both lab and pilot scale
c) From the variations of matrix polymer, compatibiliser and filler types in the "conventional" compositions (organoclay & compatibilisers) the matrix variation seems most promising in optimising the performance
d) Only a limited part of the project work was dedicated to "new approaches" with significant cost-saving potential; only the combination of untreated montmorillonite with PA-6 yielded some useful results, but will however require significant further development
e) Conventional compounds with micronised talc can also gain from using a two-step compounding process; the improvements in mechanics & shrinkage are, however, paid for by much higher production cost
f) Retaining processability, handling and "side properties" of compounds will require attention in any case