Summary of orientation in synthetic polymers

Sections 1.3.2-1.3.5 above show that orientation is most important in the thermoplastics technologically, and we can now summarise the differences between orientation in different types of polymers by a table. 

Class of polymer Requirement for orientation Reversibility of orientation 

Thermoplastics a. ductile Draw at room or Some or all of orientation 

Thermosets temperature Draw precursor polymer Irreversible 

Rubbers before cross-linking Apply stress at room Reverses on releasing 

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