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Degradation of Cellulose Nitrate

The major causes of instability of cellulose nitrate are due to the products of hydrolytic, thermal and photochemical reactions. Degradation of the polymer is autocatalytic, that is, the products of breakdown tend to catalyse a faster and more extensive degradation reaction than the primary processes, if allowed to remain in contact with degraded cellulose nitrate. [Pg.200]

One of the first products of thermal deterioration, i.e. in the absence of light, is the highly reactive, highly toxic oxidising agent nitrogen dioxide (N02), identified by its yellow vapour and distinctive odour. This is formed [Pg.200]

Some metals, notably copper, accelerate the rate of degradation of cellulose nitrate. Copper screws and arm wires of cellulose nitrate spectacle frames [Pg.201]


Activated charcoal has been used successfully to dramatically reduce the rate of degradation of cellulose nitrate objects. The charcoal is treated with oxygen... [Pg.206]

An early stage of degradation of cellulose nitrate. A poster from the Historical Music Museum in Copenhagen, Denmark, dating from the 1950s has lost camphor and shows cracks. At this stage, the poster is highly flammable. [Pg.178]

Stewart, R., Littlejohn, D., Pethrick, R. A., Tennent, N. H. and Quye, A. (1996). The use of accelerated ageing tests for studying the degradation of cellulose nitrate. In Preprints of the 11th ICOM-CC Triennial Meeting The Hague, 12—16 September 2005 (J. Bridgland, ed.) pp. 67-970. James James Ltd. [Pg.192]

Figure 3.390. Ultrasonic degradation of cellulose nitrate [1150] (a) in ethyl acetate solution (b) in w-butyl acetate solution. (Frequency, 400 KHz power, 50 W). Figure 3.390. Ultrasonic degradation of cellulose nitrate [1150] (a) in ethyl acetate solution (b) in w-butyl acetate solution. (Frequency, 400 KHz power, 50 W).
Effect of the degree of polymerization on the viscosity. It has been made clear by the experiments of many authors that operations leading to the degradation of cellulose prior to nitration contributes to the production of a less viscous nitrocellulose. Moreover, the degree of polymerization of cellulose before nitrating depends upon the origin of the cellulose the type of plant, its age and so on. The properties of the cellulose, such as polymerization degree, are passed on to the nitrocellulose, as already stressed (p. 246), to exert an influence on the viscosity of the product. Hence cotton yields nitrocellulose solutions more viscous than these from wood... [Pg.267]

To broaden the scope of his interests, he spent another year as a postdoctoral fellow in the Physics Department of Pennsylvania State University, working on the X-ray analysis of biological compounds. Equipped with an exceptionally broad and multidisciplinary education and experience, he proceeded to The Ohio State University, Columbus, Ohio, to work with Professor M. L. Wolfrom. His initial job was to investigate the ignition of cellulose nitrate, a project left over from World War II. In Fred s hands, this project was turned into an isotopic investigation of the biosynthesis and degradation of cellulose. At this time, there was very little known about the preparation of specifically labeled sugars, let alone the biosynthesis of... [Pg.1]

The majority of investigations on the degradation of cellulose acetate have been conducted on photographic film (cellulose triacetate) rather than moulded material. like cellulose nitrate, cellulose acetate (CA) is deteriorated by both physical and chemical factors and the physical cause of degradation is plasticizer loss. Three-dimensional objects moulded from cellulose acetate comprise 20-40 per cent by weight plasticizer. Typical plasticizers include triphenyl... [Pg.180]

Clark et al [23] at the University of Durham, U.K. have applied XPS to the study of cellulose nitrate and the step by step nitration of cellulose. They have shown which hydroxyl group is most easily accessible for nitration. They have observed sulfate ester from the nitration process at the surface of the nitro cellulose, this is suspected as an initiator of the degradation of N.C. [Pg.583]

There are a variety of reaction systems that allow the formation of cellulose trinitrate [9046-47-3]. HNO in methylene chloride, CH2CI2, yields a trinitrate with essentially no degradation of the cellulose chain (53). The HNO /acetic acid/acetic anhydride system is also used to obtain the trinitrate product with the fiber stmcture largely intact (51,52). Another polymer analogous reaction utilises a 1 1 mixture of HNO and H PO with 2.5% P2O5 to achieve an almost completely nitrated product (54). [Pg.268]

The solid-state NMR technique may also be used in cellulose derivatives to follow the degree of substitution and degradation of the chain e.g. as found for cellulose nitrate 16). Investigations on the composition of copolymers may also been done as examplared by celluloseacetate-butyrate given in Fig. 6, 20). Here, owing to relaxation differences the spectra cannot be used for elementary analyses, but for estimating the relative number of the components. [Pg.7]

Cellulose nitrate (Celluloid) 1850 Moulding material, paints, glues, coatings, photographic films, varnishes Camphor, phthalate esters High flammability and degradability, with production of nitrogen dioxide... [Pg.27]


See other pages where Degradation of Cellulose Nitrate is mentioned: [Pg.427]    [Pg.200]    [Pg.201]    [Pg.177]    [Pg.180]    [Pg.192]    [Pg.196]    [Pg.221]    [Pg.80]    [Pg.234]    [Pg.109]    [Pg.427]    [Pg.200]    [Pg.201]    [Pg.177]    [Pg.180]    [Pg.192]    [Pg.196]    [Pg.221]    [Pg.80]    [Pg.234]    [Pg.109]    [Pg.198]    [Pg.250]    [Pg.261]    [Pg.336]    [Pg.156]    [Pg.464]    [Pg.392]    [Pg.261]    [Pg.336]    [Pg.202]    [Pg.207]    [Pg.113]    [Pg.181]    [Pg.195]    [Pg.199]    [Pg.201]    [Pg.247]    [Pg.284]    [Pg.255]    [Pg.257]    [Pg.297]    [Pg.301]    [Pg.836]    [Pg.400]    [Pg.142]   


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