Series editors' preface - Wood Tools

Plastics and polymers, coatings and binding media, adhesives and consolidants 129
designation of the first synthetic plastic is
rather arbitrary. However, this distinction is
often given to the cellulose nitrates. In 1846 an
explosive known as gun-cotton was made by
reacting a mixture of nitric and sulfuric acids
with cotton-wool. Experiments on this material
showed it to be thermoplastic, but highly
unstable and flammable. The extensive efforts
of Alexander Parkes in England led eventually
to a thermoplastic resin composed of less
highly nitrated cellulose combined with various
oils, fillers and pigments, and called Parkesine.
Moulded objects were made from this material
between 1855 and 1868 but suffered from
fragility. In 1869, the Hyatt brothers of Albany,
New York patented a synthetic ivory named
Celluloid made from cellulose nitrate plasticized
with camphor which was an immediate
and lasting success. The manufacturing technologies
developed to convert Celluloid and its
English equivalent Xylonite into a wide range
of useful and decorative objects formed the
basis of a plastics industry which grew and
flourished as further discoveries were made.
A thermosetting, crosslinked resin synthesized
from phenol and formaldehyde was
patented by Leo Baekeland in 1907 as Bakelite.
Bakelite could be produced in any colour (that
allowed for its natural yellow tint), was very
hard and rigid and found extensive use in early
radio cabinets, automobile components and
other high-tech applications.
In 1922, a great impetus was given to the
synthesis of further plastic compounds by the
work of Hermann Staudinger. In the process of
synthesizing rubber, Staudinger identified and
described the essential linear structure of polymers.
A more sophisticated understanding of
polymer structure gave rise after 1930 to a
rapidly growing list of ‘plastics’ arrived at by
deliberate chemical engineering rather than
trial-and-error or chance discovery. After the
Second World War, furniture made entirely of
plastics became increasingly popular (e.g. see
Katz, 1984). Clear acrylic sheet (Perspex ® ,
Plexiglas ® ) made from poly (methyl methacrylate)
was extensively employed but was soon
found to be brittle and easily scratched. A summary
of the main synthetic polymer materials
is given in Table 4.1.
Perhaps the category of plastics most important
to furniture history and manufacture are the
composites or laminates. Composites are com-
binations of dissimilar materials that show
properties different from and often superior to
the individual ingredients (Gordon, 1976). This
is a very old concept and in many ways
describes all of the materials discussed so far
in that they are almost never pure substances.
An early example of structural composites
showing high strength combined with low
weight were the papier mâché panels used to
form furniture (see section 5.4). Gypsum plaster
and coarse weave jute or hemp layered into
moulds or built up on wooden armatures were
extensively employed for the realization of
complex architectural interiors and even entire
exhibition buildings. Such ‘fibrous plaster’ or
‘staff’ filled the functions of what is today commonly
called ‘fibre-glass’.
Fibre-glass is a rather misleading term for
resin and glass-fibre composites more properly
called glass reinforced plastics or GRPs. Such
composites use glass fibre in the form of cord,
cloth or randomly oriented felt-like matt which
is impregnated with thermosetting resins such
as phenolics, epoxies and polyesters. They are
very strong, relatively light in weight and have
been used to manufacture furniture since the
1940s.
Paper-based composite laminates have also
found extensive use in furniture as surface coverings.
Laminates such as Formica ® , based on
paper and melamine resin, have been used to
copy every variety of wood and stone.
Synthetic polymers had a revolutionary effect
on the textile industries and synthetic fibres
were quickly brought into use in upholstery.
Uses of polymers in upholstery are described
in Chapter 3. Polymer foams can be thought of
as composites of resins and gas bubbles. They
can be made either soft and flexible or hard
and rigid depending on resin composition and
bubble size. An extremely readable review of
the technology of fibres, plastics and rubbers is
given by Kaufman (1968). Kovaly (1970),
Buttrey (1976) and Seymour and Mark (1990)
provide further information on the utilization
of plastics in furniture and as industrial finishes.
Polymers that become soft or fluid when
heated have had various applications in
moulding and casting. Historically they have
been used to produce rigid moulds. Decorative
plasterers have used mixtures of waxes, resins
and fillers to produce moulds for repeat pat-