Coagulation and structure formation

The actual formation of the fibers and films in a spinning or extrusion process takes place during coagulation of the lyotropic solution. In this process step a phase transition to the solid state is induced by a non-solvent. The conditions of the coagulation process, e.g. the concentration of the polymer solution, the composition and the temperature of 

Pertinent data on the solvate crystals of PpPTA with sulfuric acid have been given by Arpin et They found two crystal modifications 

Detailed investigations of the coagulation of PpPTA films from sulfuric acid solutions in various coagulants have been carried out by Haraguchi et They found that films coagulated in organic liquids showed 

In a recent study Roche et al performed coagulation experiments with films prepared from a 20% (w/w) solution of PpPTA in sulfuric acid.  

A study on the coagulation of PpBA films from solutions in N,N -dimethylacetamide with LiCl in a magnetic field was reported by Takase et Good uniaxial orientation with the chains aligned parallel to 

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