Side‐chain type benzoxazine‐functional cellulose via click chemistry

Abstract

A side‐chain type benzoxazine‐functional cellulose has been developed using click chemistry via the reaction of ethynyl‐monofunctional benzoxazine monomer and azide‐functional cellulose. The synthesis, crosslinking, and thermal properties of the benzoxazine‐functional cellulose are studied by NMR, FTIR, DSC, and TGA. The crosslinking reaction of the benzoxazine side‐chain unusually takes place at low‐temperatures in comparison to an ordinary benzoxazine resins. Upon crosslinking, the polymer shows high char yield of 40%, which is a marked improvement from a mere 4% of the unfunctionalized cellulose. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Highly Improved Thermal Properties of Hydroxyl‐Containing Polymers via Modification by Benzoxazine Groups

“…Shoulder of benzoxazine polymerization of PVA–4HBA‐a is the combination of benzoxazine polymerization exotherm and unreacted PVA decomposition endotherm (Figure 5). As previously reported, similar catalytic effect of hydroxyl group has also been observed on cellulose with 4HBA‐a side chain 9…”

“…In accordance with reported trend, the material shows improved thermal stability at 50% conversion of hydroxyl groups to polybenzoxazine. By using isocyanate to append benzoxazine groups, the result offers a more cost‐effective method than the previous method of appending benzoxazine onto cellulose via azide and alkyne reactions 9. By using isocyanate reactions, desirable effects on physical properties can be obtained without costly azide reactions or alkyne reactions.…”

“…When 1,3‐benzoxazine polymerizes, it undergoes near‐zero volume shrinkage,5 gains high thermal6 and chemical7 stability, and exhibits unusually low surface energy 8. If non‐polymerized benzoxazine group is part of a polymer material whether it is in the main chain itself,9–15 as a side group,16–19 or as a terminal group,20–22 the material exhibits thermoplastic properties such as solubility in common solvents and film forming. These polymeric benzoxazine molecules can then be heated with or without added initiators and/or catalyst to form cross‐linked polybenzoxazines.…”

Syntheses of new antimicrobial cellulose materials based 2-((2-aminoethyl)amino)-4-aryl-6-indolylnicotinonitriles

“…The broad spectrum antimicrobial properties of amino cellulose as well as their good biocompatibility made them suitable candidate for the design of novel amino cellulose biopolymers through the chemical grafting of cellulose by amino compounds. Recently, there is an increasing interest for the preparation of new amino cellulose derivatives for their potential applications in different research fields, such as anion-exchange resin, selective membranes [12,13], anticoagulants, biosensors, enzyme immobilization in bioassays [14][15][16], flame retardants [17], and antimicrobial agents [18]. The antimicrobial activity of the modified natural polysaccharides, such as some chitosan and starch derivatives encouraged their use in the manufacturing of packaging materials.…”

Tailor-made and chemically designed synthesis of coumarin-containing benzoxazines and their reactivity study toward their thermosets

“…The feasibility of using biomass renewable resources as raw materials for the synthesis of benzoxazine resins has been reported by not only substituting the phenolic moiety but also the amine portion of the resins. Expectedly, attempts were also made to replace both the phenolic and the amine moieties, placing the benzoxazines as pending groups in existing natural occurring polymers, and copolymerizing benzoxazines with natural renewable oligomers …”