ON- POLYMERS - ezio martuscelli

Iii) Synthetic Plastics- they are newly synthetised by the man starting from small molecules, called
monomers. The “Era” of synthetic plastics begun in 1908 when Leo Hendrix Baekeland patended
the synthesis procedure and the method of processing of the phenol formaldehyde thermosetting
resins ( comonly called Bakelite in honor of its inventor ).
Polyvinyl chloride (PVC), polymethyl methacrylate( PMMA) , polyethylene, polyamide (Nylon),
polyacrylonitrile, polyurethane, polycarbonate, saturated and isaturated polyester, epoxies, , teflon,
etc., belong to the synthetic era of plastics.
The number of synthetic polymers developed since the beginning of the twentieth century is
enormous. These compounds differ dramatically from each other as far as their proprties are
concerned. Thus the identification of the type of plastic from which an artefacts is made represents
one of the main problem that one must afford for the sake of their conservation.
Plastics, since the birth of the polymer industry, were preferred, in many applications, to traditional
materials such as, wood, metal, glass, ceramics, ivory, etc.
The advantages in using Plastics materials, constituted by polymer based formulations, rather than
traditional materials, were essentially the following:
---Easy processing;
---Low production cost;
---Weight saving;
---Colourability
---Innovative performances;
---High rate of production.
The disadvantages in making items in plastics were mostly related to:
---Instability against environmental and internal degradation factors;
---Necessity to use additives (stabilizers, plasticizers, fillers, aid processing etc.).
Artefacts in plastics, more and more present in private collections and in many museums including
the art museums and the science museums, may be subdivided in the following two broad
categories: artistic objects and items of historical and cultural interest.
A ) Plastics in artistic objects
Plastics had ( still have ) an important function in the structuration of works of art. They represented
( represent ) an important means of expression of artists and designers.
According to G. Williams, the reasons which convinced artists and designers, since the beginning of
polymer Era, in using plastic materials for their works, may be summarized as follows:
< It is amongst the most versatile group of materials known, with different varieties notable for
their relative strengths, ranging from total rigidity to complete flexibility, not to mention inertness
and stability. Plastics enabled the development of an infinite number of novel shapes and colours
which were impossible to achieve using natural materials. The moulding of plastic requires
expensive tooling and a high degree of industrialisation, yet the resulting products can be massproduced
cheaply and in great quantity. Versatility, novelty and the potential for replication were
the perfect qualities of any material for the manufacturers of new consumer goods > [4].