FORMATION OF CONJUGATED DOUBLE-BONDS DURING THERMAL-DEGRADATION OF ACENAPHTHYLENE-MALEIC ANHYDRIDE ALTERNATING COPOLYMER

The kinetics of polyconjugated system formation during the thermal deg radation of the acenaphthylene-maleic anhydride (ACN-MAn) alternating copolymer has been studied at 420-610 K by following the increasing UV absorbance in the region 350-700 nm. The process is described by 'ste p-like' kinetics at 420-580 K. The average values of effective kinetic parameters for the formation of conjugated structures absorbing in th e region 400-500 nm have been established. In air, the formation of co njugated bonds absorbing in the region 420-550 nm occurs more readily. The conjugated structures are oxidised at temperatures above 550 K. D ecomposition of anhydride structures is observed to occur above 580 K. The kinetics of this reaction are described by a first order rate law with rate constant k = 2.5 X 10(14) exp(-200/RT). The possible mechan ism of conjugated structure formation is discussed. (C) 1997 Elsevier Science Limited.