Nitrocellulose molecular addition compounds

From these facts it seems beyond doubt that the crystal lattice of nitrocellulose undergoes a marked deformation as the result of absorbing a solvent or gelatinizer. For the time being it is difficult to say whether a new chemical compound is formed. Nevertheless the formation of molecular addition compounds appears likely. It is also without question that addition compound are formed by nitrocellulose and camphor. According to Hess et al. nitrocellulose of 13.7% N combines with camphor in a 1 1 mole ratio (one molecule camphor to one anhydroglucose unit). 

Of particular interest in connexion with our subject is the case of compound formation by a macromolecular solid e. g., the hydrate formation by cellulose and gelatin or the formation of an addition compound between nitrocellulose and acetone. Whereas in ordinary low molecular hydrates the composition of the successive compounds X, X. HgO, X. 2HaO etc. differs considerably as regards the percentage of water and, hence, the Gibbs potentials of these compounds differ by considerable jumps, the situation is different in macromolecular substances. If e.g., each monomeric residue R of a molecule consisting of a chain of n residues can bind one water molecule, the following hydrates are possible ... 

Natural and synthetic rubber and synthetic resins are soluble in organic solvents resulting in cements, resin solutions, or lacquers. In addition, there are many cellulose derivatives, such as nitrocellulose, ethyl cellulose, and cellulose acetate butyrate, used in preparing solvent-based adhesives. Solvent-hased adhesives are also prepared from cyclized rubber, polyamide, and polyisobutylene. Low-molecular-weight polyurethane and epoxy compounds can be used with or without solvent. On the other hand, high-molecular-weight types or prepolymers require solvent to make application possible. 

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