The free radical polymerization of maleic anhydride

Abstract The homopolymerization of liquid maleic anhydride at 74.5°C. wird studied calorimetrically. The molar heat of polymerization is determined as 14±1 kcal./mole. The bulk polymerization is characterised by the high chain‐transfer, with kinetic constants C M and C I of the order 0.07 and 2.63 respectively. The ratio δ= k t 1/2 /k p is finite (∼109) and comparable to other sluggish monomers which shows that the widely accepted assumption, k p or k 22 = 0 in kinetic interpretations of copolymerization of this monomer is untenable. A copolymerization of maleic anhydride with allyl chloride gives a high monomer reactivity ratio of about 0.2 for the former and the copolymer composition well exceeded 0.5 in respect of maleic anhydride mole‐fraction, confirming self‐addition.