Plastics museum

Alfred P. Critchlow, another plastic molding pioneer, molded shellac and gutta percha in Florence, MA. His firm is now known as the Prophylactic Company. Many of these developments occurred in the area around Leominster which became a center for plastic machinery and plastic fabrication (9). Leominster is also the sight of a national plastic museum. 

Figure 1.1 shows that the methods of manufacturing (semi-)finished plastic parts involve various players equipment manufacturers, polymer producers, additive suppliers, compounders and final processors. It can be safely assumed that the compounder will continue to be the main customer for additives and additive concentrates also in the future. Finally, the recently established Plastics Additive Museum (Lingen, Bavaria), by a pioneer in PVC additives (Barlocher GmbH), shows that the business is coming to age. 

Biers, W. R., K. O. Gerhardt, and R. A. Braniff (1994), Lost Scents Investigation of Corinthian Plastic Vases by Gas Chromatography - Mass Spectrometry, Univ. Pennsylvania Museum, Philadelphia. 

National Plastics Center and Museum, http www.plasticsmuseum.org... 

Fenn,). (1995) Secret sabotage reassessing museum plastics in display and storage, in Resins-Ancient and Modem (eds M.M. Wright and J.H. Townsend), Preprints of the 2nd Resins Conference, University of Aberdeen, 13-14 September 1995, Scottish Society for Conservation Restoration, pp. 38—41. 

Bob bangs on the carbon doors that separate the museum corridor from Miss Muxdroozol s living quarters. Humanity entered the Carbon Age years ago, after soccer ball shaped cages of carbon atoms led to extraordinary new materials. The new materials are a hundred times stronger than any metal and weigh less than ordinary plastics. Unfortunately for Bob, they also block sound very efficiently. 

Crystallinity indexes calculated according to the method described by Segal et al. (32) showed that the old cotton has a crystallinity of about 38 . Aqueous treatments increased the crystallinity of the historic cotton sample to about 45 . However, the crystallinity of contemporary cotton, which is about 70 , was not reached (30). This increase suggests that water acts as an internal plasticizer and allows a segmental reorientation which leads to an increase in crystallinity. Water-induced crystallization of amorphous cellulose fibers has been reported (17). Kalyanaraman (33) investigated orientation factors of cotton fibers from historic samples and found that the orientation values of the museums samples are smaller than the values of present-day cottons. He opined that cotton may have lost its orientation over time. In view of this... 

Galicia (in the Austro-Hungarian Empire) deserves mention. Luft obtained a patent in England ( 10,218) in 1902 for the "Process for Producing Plastic Compounds 1 from phenol, formaldehyde and sulfuric acid. It was an awkward process, Sir James Swinburne (Courtesy London o but Luft made several samples. Enter now Science Museum).. ... 

Hansen, C.M., Hansen Solubility Parameters. A User s Handbook, CRC Press, Boca Raton, EL, 2000. Shashoua, Y., Permanence of plasticizers in polyvinylchloride objects in the museum environment. Polymer Preprints, 41(2), 1796-1797, 2000. 

Museum objects are rarely collected for their material type but because of their origin, function, design, rarity, cultural or historical significance plastic... 

Today, almost all international museums and galleries possess collections which contain plastics. Plastics may be identified within building materials, defence equipment, ethnography, furniture, housewares, information technology, medical and sports equipment, modem art, photography and toys. Many combine metals, textiles and wood with plastics in their construction. In addition to the objects themselves, many of the materials used to store, transport and display them are also plastics. While museums continue their policy to collect objects that reflect both everyday life and historical events, the proportion of plastics in museums will increase. 

Since the properties and degradation reactions of plastics are usually influenced by their formulations and manufacturing processes, this chapter will first discuss those areas. Four plastics have been identified as being more vulnerable to degradation than others in museum collections cellulose nitrate, cellulose acetate, plasticised PVC and polyurethane foam. The most frequently seen... 

Ability to remain in the formulation throughout the intended useful lifetime of the plastic and not to migrate out or evaporate. The intended useful lifetime of most plastics is between one (polyethylene carrier bag) and 30 (unplasticised PVC window frames) years museums aim to keep them for longer... 

The most widely available technique for identifying mainly polymer, but also additives in plastics, is Fourier Transform Infrared (FTIR) spectroscopy. Samples are exposed to infrared light (4000-400 wavelengths per centimetre or cm ) causing chemical bonds to vibrate at specific frequencies, corresponding to particular energies. In the last 5 years, an accessory for FTIR has been developed, which enables non-destructive examination of surfaces and so is ideal for analysis of plastics in museum collections. Attenuated Total Reflection-FTIR (ATR-FTIR) requires samples to be placed on a diamond crystal with a diameter of 2 mm through which the infrared beam is reflected... 

A survey of plastics-containing objects in the British Museum and the National Museum of Denmark showed that 1% of objects were actively deteriorating and were in immediate need of conservation, while 12% exhibited deterioration and required cleaning, stabilising and repair. All the acute objects contained cellulose nitrate, cellulose acetate, plasticised PVC or polyurethane foam. Most objects (60%) were defined as being of low conservation priority, that is, they were in a stable condition but needed some treatment such as cleaning. Only just over one quarter required no conservation treatment. In general, deterioration of plastic objects in museums is visible within 5-25 years of collection. 

It should be remembered that most museum objects have been used or displayed before they are collected. They have an unknown past, usually, which contributes greatly to the rate and type of deterioration. Instability of the earliest plastics, cellulose nitrate and acetate is expected due to their poorly stabilised formulations and because they are the oldest man-made plastics in museums. However, PVC was first developed in 1926 and is still in use, so its deterioration is rather unexpected. 

Degradation of plasticised PVC materials in museums is frequently observed as migration of the plasticiser from the bulk phase to surfaces. From there, plasticiser evaporates at a rate dependent on its vapour pressure. This process may be detected as a tacky feel to the plastic, increasing brittleness and subsequent discolouration of the PVC polymer itself. The mechanism by which... 

Deterioration of plastic objects in museums has only been recognised as an important area worthy of research since 1991, while the scope of the problems surrounding the preservation of modern art has only been appreciated internationally as recently as 1998. Little is known about the conservation of plastics compared to other materials found in museums. To date, few conservation practices have been established, and development of new treatments is far slower than most degradation processes. Once deterioration has started, it cannot be stopped or reversed, but only slowed. 

This is rather contra-intuitive. Museum conservators and designers are usually advised either to improve ventilation or to include adsorbent materials to remove volatile degradation products from the air space surrounding plastic objects during storage. This would accelerate the loss of plasticiser and thereby reduce the longevity of both new and deteriorated PVC objects. 

C. Ward and Y. Shashoua, in Interventive conservation treatments for plastics and rubber artefacts in the British Museum, 12th Triennial Meeting of ICOM-CC, vol. 2, pp. 888-893 J. Bridgland (ed), James and James, London, 1999. 

Fig. 17.2. Photos showing automotive parts molded from soy plastic (1939), an exhibit dash incorporating soy plastics (1940), and a plastic bodied car made from soy plastics. Photos from the Collections of the Henry Ford Museum.

Unfortunately, over time, the plasticizers can leach out and form a sticky layer on the plastic. This is worrisome, because such substances have been linked with estrogenic effects, which (with a stretch of the imagination) may have an impact on children who handle old dolls or—even worse — put them in their mouths. It s also a problem for doll collectors and museum curators, since the leaching causes the plastic to degrade and crack. As PVC breaks down, it releases hydrochloric acid, which speeds degradation. 

For the early history of Beetle see lecture given by Kenneth M. Chance, managing director of British Cyanides, at the Science Museum, London, on the occasion of the 1933 plastics exhibition. The Plastics Exhibition, 1933. Twelfth lecture. Plastics Urea-formaldehyde types and their uses, British Plastics and Moulded Products Trader, 5 (1934), 313-318. This journal was founded in 1929, as the official organ of the British Plastic Moulding Trade Association (from 1933, the British Plastics Federation). 

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