Copolymerization of the pair maleic anhydride–dicyclopentadiene: I. Copolymerization and post‐copolymerization at high conversion

Abstract

The present study describes the kinetic investigation of the complex binary copolymerization system maleic anhydride (MA)—dicyclopentadiene (DCPD). All syntheses were carried out in homogeneous solution; high conversions in soluble and linear copolymer are achievable when starting from an equimolecular monomer feed. Excess of DCPD would limit the attainable conversions, while surplus of MA would induce crosslinking of the copolymers. The findings of the thorough kinetic study were sustained by structural assessment from IR and NMR spectra recorded for various copolymers, both soluble and gels. Copyright © 2004 Society of Chemical Industry

Copolymerization of the Pair Maleic Anhydride‐Dicyclopentadiene: II. Kinetics at Low Conversion

“…The earlier two papers dedicated to this topic (3,4) presented rather contradictory results; moreover, the conclusions regarding either the reaction mechanism, or the structure of the products obtained are completely different. Recent studies published by us (1,5) have only partially confirmed Gaylord's or Rzaeva's reports. Even if cross propagation represents an important step, nevertheless, the classical models (with or without CTC) cannot satisfactorily describe the abovementioned process.…”

“…Intrinsic viscosities measured for the reaction products are within the range 4 4 8 ml/g, regardless the composition and/or conversion. According to some previous studies (1,5), these values would correspond to M n being placed between 2 Ã 10 3 and 3 Ã 10 3 . Consequently, measuring N percentage in copolymer gives quite accurately, its structure, written as R 0 (MA) n1 (DCPD) n2 .…”

“…We reported the behavior of the MA/DCPD in radical copolymerization system in a previous paper (1). Copolymerization of MA with DCPD represents a less studied process when compared with other co-polymerizations involving MA (i.e., with other linear, or cyclic olefins or diolefins (2a).…”

“…Experimental MA, DCPD, as well as dioxane (D), used as solvent for the copolymer, have been purified as previously described (1,4). Previously, azo-iso-butyro-di-nitrile (AIBN) and lauroyl peroxide (LP) have been purified by recrystallization.…”

“…The gravimetric method implies carrying out copolymerization in reactors and taking samples at pre-established times; the copolymer has been separated by precipitation and washing in ethyl ether. High conversions may be reached by gradually adding new amounts of AIBN; this technique has been previously described (1). For copolymerizations performed within a dilatometer, LP has been used as initiator; the reaction product was finally isolated as described above.…”