Maleic anyhydride

Catalytic oxidation of n-butane at 490° over a cerium chloride, Co-Mo oxide catalyst produces maleic anyhydride ... 

The reasons for the use of maleic anhydride instead of other anhydrides or unsaturated carboxylic acids is not clearly stated in Chapter 10. If you possess an extensive knowledge of chemistry, you will know that maleic anyhydride is a cheap, safe, readily reactive compound which puls carbor lic acid sites onto a polymer by formation of a carbon carbon bond. The reaction is specific as long as aliphatic or aromatic groups are the only functional groups in the polymer being grafted. 

---