Structure study of the furan–maleic anhydride copolymer

Abstract

A structural study of furan–maleic anhydride copolymer (F–MAH) was undertaken to confirm its alternating nature and to determine its microstructure. The spectral properties of a model compound representing the alternating repeat unit, 2‐(2‐tetrahydrofuranyl)succinic anhydride, were compared with those of F–MAH. Their infrared (IR), 1H, and 13C nuclear magnetic resonance (NMR) spectra (after compensating for the absence of the olefinic double bond) were in good agreement with those of the copolymer. Furthermore, the observed splitting in the 1H‐ and 13C‐NMR spectra of F–MAH were assigned to cis–trans linkages on both the F and MAH units, with cis linkage being favored on both units, especially the former. The structure of 2,5‐dimethylfuran (DMeF)–MAH copolymer is similar to that of F–MAH copolymer, except that the preference of cis linkages is less pronounced. The structure of 2‐methylfuran (MF)–MAH copolymer is a complex structure with numerous 2,3‐furandiyl units. A mechanistic study was undertaken to elucidate the roles of F–MAH Diels–Alder adduct, and the charge‐transfer (CT) complex in the radical initiated copolymerization. The adduct reverted substantially to monomers under the reaction conditions; but, the amount of adduct remaining at equilibrium was quite appreciable; therefore, its participation could be ruled out on this basis alone. However, on polymerizing the adduct in the presence of F‐d4, the latter was incorporated into the copolymer to an extent indicative of free monomer exchange. Therefore, the adduct cannot be directly involved in the polymerization.

Co-Polymerization of Maleimides and Vinyl Ethers: A Structural Study

“…3.36, 28 3.2 27 45, 28 39.83 27 trans-1,2-cyclohexanedicarboxylic anhydride (in CDCl3) 2.95, 28 2.85 27 47, 28 45.60 27 maleic anhydride-tetrahydrofuran copolymer 29 3.3, 3.5 46.6, 49.1 model compound maleic anhydride-tetrahydrofuran 1:1 adduct 30 3.3 44.2 cis-2,3-dimethyl-N-ethylsuccinimde 31 2.95 ... trans-2,3-dimethyl-N-ethylsuccinimde 31 2.41 ... maleic anhydride-methyl vinyl ether copolymer 32 ... 51.6-48.4, 41.1-37.8 2-propenylisocynate-maleic anhhydride copolymer 26 3.82 (cis) and 3.68 (trans) 57, 59 and 62, 64 thermally induced copolymerization is also significant.…”

Synthesis of copolymers from 3,5-dioxo-4,10-dioxatricyclo-[5.2.02,6]dec-8-ene and vinyl monomers by photopolymerization and their biological activities

“…It has not only broad biological functions such as antitumour, antiviral, antibacterial, interferon-inducing and antifungal activities,1h4 but also various toxic side e †ects such as pyrogenicity, thromobocytopaenia, inhibition of microsomal enzymes, sensitization to endotoxin, liver damage, organomegaly and depression of the reticuloendothelial system.5 Therefore many attempts have been made to obtain a polymeric drug such as DIVEMA with high antitumour activity and low toxicity.6h9 Several studies have also been made in our laboratory to develop polymeric antitumour agents.10h17 However, the synthesis and biological activities of polymers containing the 3,5-dioxo-4,10-dioxatricyclo[5.2.02,6]dec-8-ene (DDTD) moiety have not been reported in the open literature because this monomer dissociates into furan (F) and maleic anhydride (MAH) above 50¡C. 18 The aim of this study was to develop new polymers from DDTD which had good antitumour activity. DDTD was expected to show considerably higher antitumour activity and lower toxicity because its polymer contains cyclic ether and dicarboxylic acid groups some distance from the main chain, in contrast to DIVEMA which has the same groups attached directly to the main chain.…”

Bioengineering functional copolymers. XV. Synthesis and characterization of poly(N‐isopropyl acrylamide‐co‐3,4‐dihydro‐2H‐pyran‐alt‐maleic anhydride)s and their PEO branched derivatives

“…The results obtained by authors indicate that the reactivity of the comonomers to form alternating copolymers with MA is governed by the resonance stabilization of the monomer and to a lesser extent by complex formation. The formation of CTCs in the maleic anhydride (MA)‐donor heterocyclic monomers system observed by many researchers, which are studied the complex‐radical copolymerization of MA with various electron‐donor functional monomers such as benzofuran, indole, and benzothiophene,14 p ‐dioxene,3, 15 p ‐oxathiene,1 dihydropyranes4, 6 and thiophene16 in detail. MA is known to form an alternating copolymer with electron‐donor heterocyclic monomers such as thiophene and its 2‐methyl or 3‐methyl derivatives,17, 18 having repeating units of structures with 2,5‐linkages and mainly 2,3‐linkages across the methyl‐substituted derivatives.…”