Cellulose, chain scission derivatives

Scheme 7 Cellulose-chain scission as a consequence of homolytic reactions involving NMMO-derived radicals...

Chemical cellulose esters are relatively stable to UV radiation since they lack aromatic chromophores. Even so, exposure to UV radiation may cause some chain scission and loss of physical properties in cellulose esters exposed to outdoor environments esters formulated for such use must be stabilized accordingly. Some resorcinol and benzophenone derivatives, such as resorcinol monobenzoate and 2-hydroxy-4-methoxybenzophenone, are reportedly excellent UV-light stabilizers for cellulose esters (56,57). Other stabilizers include piperidine derivatives (58) and substituted triazole compounds alone (59) and in combination with resorcinol monobenzoate (60). 

Cellulose is a major naturally occurring storage and structural polymer in plants. Cellulose and its derivatives have been widely investigated for various biomedical applications. Although pure cellulose is not readily resorbable in the body, it can be chemically modified to cause chain scission of the structure and hence be made bioresorbable. Oxidized cellulose is one such example. Surgicel is a commercial oxidized cellulose, which is available in the form of gauze pads for use as resorbable hemostatic wound dressings. 

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