SAMPE Journal - May/June 2022 - 52

FEATURE / THERMOSET COMPOSITES RECYCLING
CONCLUSIONS
Patent documents are valuable sources of technical
and commercial information. Knowledge about
the existing intellectual property as preparation
for strategic planning within a company becomes
increasingly important as the innovation processes
become more complex, the innovation cycle
becomes shorter, and the industry becomes more
competitive. Despite a few limitations, patentmapping
can quickly provide a broad overview of
a technology sector, its components, players, and
history.
The methodology employed in this paper
provided a valuable map for the development of
the technologies used in composites recycling. The
methodology required some expertise to properly
design the patent searches to generate the map,
but subsequent analysis is a learning process that
can be done by non-experts in the field. The depth
of the information obtained through the patent
map was equivalent to what could be obtained in
scientific databases, and superior in some ways,
for the purpose of strategic planning within a
company.
The patent map shows that composites
recycling emerged before 1990 but significantly
increased after 2000, driven by regulations and
tax incentives resulting from environmental and
social pressures. The majority of the patents are
still active, demonstrating a sustained interest in
commercial
exploitation. The key technologies
used in composite recycling can vary depending
on the type and dimensions of the composite
material to be recycled, but they can be basically
divided into: disassembly, grinding, separation
of components, and utilization of recyclates.
Approximately 24% of the patents correlate to
disassembly and grinding, indicating a high level of
difficulty to perform this operation. The separation
of components corresponds to approximately 46%
of the patents and the two main processes are
chemolysis and pyrolysis. Patent data indicates
that chemolysis seems to be gaining strength with
time and new technologies in pyrolysis have also
emerged. The design of new materials to enable
an easier recycling process emerged circa 2010
and has gained strength since. Many of these new
materials are based on epoxies or modified epoxy
technologies.
The overall objective of composite recycling
is to mitigate the environmental impact of the
growing volume of composite
waste and to
maximize the resources used in composites. But
the patent map reveals additional details for these
objectives indicating the use of recyclates which
52 | SAMPE JOURNAL | MAY/JUNE 2022
can be divided in three major groups: fiber recovery
(in particular carbon fiber recovery), use as fillers
for thermosets, thermoplastics or other materials
(concrete, wood particle board, etc.), and direct use
of parts or pieces in other products (panels, railroad
ties, etc.). The patent map on composite recycling
also reveals two major areas with significant recent
patent activity that indicate potential spaces for
innovation and should be further analyzed: circuit
board and wind turbine blade recycling. The patent
map provides a framework that can facilitate the
exploration of these areas.
The success of composite recycling depends
on the development of a holistic approach that
includes all steps of recycling, from disassembly
of large composite parts such as wind blades, to
the final destination of the recyclates. Therefore,
it requires the development of a value chain that
includes the end of life of products. The patent map
shows the inception of new technologies that can
support accomplishing this objective, such as the
development new materials to facilitate recycling
of composites or process developments that take a
holistic approach; minimizing the environmental
and social impact of the means and resources used
for recycling, while maximizing the benefits at the
end of life of the composites.
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Media editorial 5/18/2021.
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