Swelling stage

The nature of solubility and the strength of solvent. According to present views the dissolution of cellulose esters consists in the separation of the chain-molecules under the specific influence of the solvent until all bonds between the chains disappear. The macromolecules of polymer can slide apart even at the swelling stage. Because of their elasticity, it is possible that the chains can be pushed aside in certain places or along the entire molecules. Further, a shortening of chains occurs, but being a secondary effect it proceeds slowly. 

One major difficulty with stripping film is that the film may move relative to the specimen during processing. This is usually avoided if the swelling (stage 5) and drying processes are adequate. 

Restricting ourselves to the first term of a series Eq. [6.1.42], we can write for the final swelling stage the equation of kinetic curve... 

Refers to the elapsed time after an adhesive is applied until pressure effects curing. Intermediate-stage reaction step for various thermosetting resins. During this stage the material swells when in contact with certain liquids and... 

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