Cross-Linking, Plasticizers, and Fillers

The above provides a brief introduction to simple homopolymers, as made pure. Only a few of these are finally sold as pure polymers, such as polystyrene drinking cups and polyethylene films. Much more often, polymers are sold with various additives. That the student may better recognize the polymers, the most important additives are briefly discussed. 

On heating, linear polymers flow and are termed thermoplastics. To prevent flow, polymers are sometimes cross-linked ( )  

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