Reactions of some phosphorus compounds with cellulose dissolved in aqueous alkaline solution

Abstract

Dissolution of cellulose in aqueous hydroxide offers a procedure for regeneration of cotton or wood celluloses. The aqueous NaOH system for dissolving cellulose seems to have considerable potential for fiber production and also as a medium for preparing cellulose derivatives. Reactions with phosphoric and phosphorous acids, phenyl-and phenoxy phosphonic dichlorides, and an amido phosphite oligomer on aqueous dissolved cellulose are described. The resulting products are characterized by analytical and spectral methods (infrared and X-ray diffraction) to determine phosphorus and nitrogen content, substitution degree, and polymerization degree. Particular attention was given to the effects produced by chemical modification on the crystalline pattern of microcrystalline cellulose. Some remarks are also made about the thermooxidative behavior of phosphorylated cellulose.

Phosphorylation of bio-based compounds: the state of the art

“…Since more than 60 56,57 They claimed that the NaOH treatment breaks the van der Waals and hydrogen bonds between cellulose molecules, which causes more hydroxy groups to become exposed to H 3 PO 4 in the second step of the process. After the NaOH pre-treatment, Li et al have rinsed the fibers and then reacted them with phosphoric acid in DMF at 154 °C.…”

“…Few reports described the successful phosphorylation with phosphorus acid in absence of urea. Petreus et al 57 dissolved cellulose in aqueous NaOH and reacted the mixture with H 3 PO 3 or with amido ethyl phosphite oligomers ( Figure 1.A) yielding compounds with DS ranging from 0.4 to 0.7.…”

Characterisation and properties of homo- and heterogenously phosphorylated nanocellulose

“…The latter are usually applied as homogeneous chemical reactions using mainly toxic reagents and organic solvents that result into partial or total disruption of the original fibrous integrity. The synthesis of phosphorus cellulose derivatives has thus been performed in various solvents [dimethyl sulphoxide (DMSO)-methylamine, DMAc-LiCl, SO 3 -triethylamine, formic acid, trifluoroacetic acid, N,N-dimethylformamide (DMF)-N 2 O 4 , paraformaldehyde, trimethylchlorosilane-DMF, urea in melt or aqueous-NaOH], with many variants of phosphorous compounds (phosphoric and phosphinic acids, phosphorus oxoacids, phosphorus pentoxide, amidophosphates, alkyl or aryl derivatives of phosphorous acids) (Granja et al, 2001a(Granja et al, , 2001bIsogai & Atalla, 1998;McCormick, Callais, & Hutchinson, 1985;Nifant'ev, 1965;Oshima et al, 2011;Petreus, Bubulac, Petreus, & Cazacu, 2003;Ramos, Assaf, El Seoud, & Frollini, 2005). The highest substitution degree (DS between 1 and 2.8) of water soluble phosphorylated cellulose was obtained from the reaction of MCC with phosphorous acid/urea, either in melt (Inagaki, Nakamura, Asai, & Katsuura, 1976;Suflet et al, 2006) or subsequently to microwave activation (Gospodinova et al, 2002).…”

Vapor Phosphorylation of Cellulose by Phosphorus Trichlo-Ride: Selective Phosphorylation of 6-Hydroxyl Function—The Synthesis of New Antimicrobial Cellulose 6-Phosphate(III)-Copper Complexes

“…Physical chemistry of cellulose-phosphates (III and V) has been well documented in the literature [ 13 ], however in the majority concerning cellulose dihydrogen phosphates(V) Cell- O -P(O)(OH) 2 , and with much less dealing with cellulose hydrogen phosphates (III) Cell- O -P(O)(OH)-H and derivatives [ 29 , 30 , 31 , 32 , 33 , 34 ].…”