It all depends upon the specification of the product being
manufactured, the weight of the product and the required consistency of
the core foam, but can include all polymer families in a co-mingled
state, including high melt temperature materials.

If domestic plastic waste was made up of varying percentages of a fairly
predictable suite of polymers. And this blend just for instance was always
between 0 - 66% of Polyethylene (various grades), 0 - 66% Polypropylene
(various grades) and 0 - 66% PET (Polyethylene Terethphalate), 0 - 10%
Other polymers e.g. Nylons, acrylamides etc. This definition obviously
allows for considerable batch to batch variation in the "waste"
and these are purely invented numbers. For typical products, good results
are obtained with a majority percentage of "olefinic" (LDPE,
HDPE or PP) in the core. This blend of materials can usually consist of
co-mingled post consumer waste, blended with other recycled PE materials,
such as used agricultural film, post industrial use PE, pulverised polymer
material from WEEE recycling and/or Virgin material. These materials can
also include non-polymer contamination such as paper. We have to blend
post-use recycled materials from several sources to obtain consistent
batches for optimal consistency, but there are product opportunities that
can use over 90% co-mingled plastic waste. The first trials of eco-sheet
have used over 75% waste electrical (WEEE) material with considerable
success.

Does this process tolerate additional (to those already in waste plastics)
fibre reinforcement materials, or other inert filler materials and if
so what impact, if any, would including them have on the preparation and
processing of the "powder"? Short fibres actually benefit the
performance of products being manufactured. Long fibres can cause issues
in delivery into the mould, but can be size reduced prior to delivery
into the PIM mould.