Reaction of Cellulose with Aqueous Solutions of Orthophosphoric Acid

Experimental data were obtained that suggest that total amorphization of hydrated cellulose is attained in 79-80% aqueous solutions of H₃PO₄. The reaction of cellulose with aqueous solutions of H₃PO₄ is accompanied by selective sorption of molecules of the acid. Aqueous, especially concentrated, solutions of H₃PO₄ are characterized by low wetting power with respect to natural and hydrated cellulose.     

“Elastic recoil” in polymer solutions as a function of concentration

The critical concentration C_c corresponding to formation of a continuous structural network was determined as a measure of elastic recoil in polymer solutions. It was shown that C_c is not related to deformation parameters but reflects the transition from one molecular-kinetic state to another in the material under investigation.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 20, No. 2, pp. 197–199, February, 1971.     

Flow of polymer melts through channels of triangular cross section

Analyzed is the problem of a completely steady isothermal flow of non-Newtonian fluids through channels. A close agreement between theoretical and experimental data has been established.ranslated from Inzhenerno-Fizicheskii Zhurnal, Vol. 23, No. 2, pp. 328–335, August, 1972.