Age of cellulosic textiles

Celluloses are similar to other linear polymeric materials in that they can possess one-dimensional order within an individual chain as well as three-dimensional order within an aggregate of chains. Increments in the levels of order occur during the isolation of native celluloses and also as a result of exposure to conditions that promote molecular mobility, such as elevated temperatures and immersion in plasticizing fluids. These increments generally result in embrittlement of the cellulosic materials. Similar effects are expected to occur upon aging of cellulosic textiles and papers over extended periods, and may be accelerated by hydrolytic cleavage of cellulosic chains. The implications of these effects for conservation practices, both with respect to recovery of function as well as in the assessment of deterioration, are reviewed. 

Accelerated Aging of Cellulosic Textiles at Different Temperatures... 

Absorbance of ninhydrin solution silk fabrics after heating, 120-22,125 silk fabrics exposed to light, 123-24 Accelerated aging of cellulosic textiles, effect of... 

Adsorption of transition metal species during processing, cellulose, 388 Advisory panels for standards for archival materials, potential benefits, 311 Age of cellulosic textiles determination from single-fiber creep measurements, 19-38 effect on crystallinity, 417 effect on rate of degradation, 416-17 Aged paper... 

Effect of Alkaline Deacidifying Agents on Naturally Aged Cellulosic Textiles... 

Linen textiles made from flax fibers have been known and used by mankind since antiquity (1 ). Flax has been used in many textile constructions including fine linen fabrics, laces, embroideries, and bridal fashions, and many historic linen textiles have become part of permanent museum collections. Older linen fabrics and laces are prized for their natural creamy color and luster and often have been recycled and reused. However, little is known about natural aging of linen. Most aging studies for cellulosics such as linen have involved accelerated heat-induced aging. 

Alkaline-deaddifying-agent effect on naturally aged cellulosic textiles abrasion resistance of fabrics, 151,152r,153,154f accelerated aging procedure, 146 aqueous-extract pH of fabrics, 149,150r,151... 

Recent approaches directed toward preventing oxidation of cotton cloth included using accelerated aging of alkaline-treated cotton cloth for neutralization of acidic, oxidized, cellulose decomposition components that in cellulosic textiles and in paper are responsible for age tendering and yellowing. Conclusions regarding the relative effectiveness of treatments at room temperature were based on results of treatments at one elevated temperature (8). Predictions of long-term effects of these treatments are unknown (9). 

Application of Additives to Silk. Deacidifying Agent. This material is ethoxymagnesium ethyl carbonate dissolved in trichlorotrifluoroethane (Wei To Associates). It has been extensively used as an alkaline buffering agent to protect paper and cellulosic textiles from aging (7,8,21). Samples were dipped one at a time in the solution for 30 s and then dried flat on a sheet of poly(methyl methacrylate). The treated samples had an add-on of approximately 3% and were relatively stiff. 

Alkaline degradation reactions are largely controlled by the carbonyl content of cellulose (27-29). Because the carbonyl levels go up as natural aging proceeds, one should expect that an 800-year-old textile would be much more likely to be adversely affected by alkali than would new, unoxidized cellulose. The vast majority of the conservation... 

The paper and textile industries have been concerned about the aging, deterioration, and degradation of cellulosic materials at elevated temperatures for practical reasons, such as the performance of tire yarn and electrical insulation paper, and the problems involved in drying or processing the cellulosic materials in general. However, due to the practical nature of these problems, the reactions involved have often been measured in terms of loss of strength and other physical properties. 

The application of IR spectroscopy with respect to the characterisation of cellulosic (plant) fibres is demonstrated. The ability to characterise fibres is of importance to textile conservators, as this information aids in the determination of the age and origin of the artefact from which they are taken, and may influence the choice of treatment. The fibres under examination are taken largely from the bast group (flax, hemp, jute and ramie) in addition, sisal and cotton are compared. FT-IR microspectroscopy and ATR techniques are employed. To complement the conventional use of these methods, the inherent polarisation effects of the equipment are exploited to record polarised IR spectra. Jute, sisal and cotton are readily differentiated, but flax, hemp and ramie prove more difficult to distinguish. Peak ratio techniques are apphed in the latter case. 2 refs. 

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