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This paper reports on a headspace gas chromatographic method (HS-GC) for rapid determination of degree of substitution in succinic anhydride (SA) modified celluloses. The method is based on the reaction between the carboxyl groups in SA modified cellulose and bicarbonate solution in a closed headspace sample vial. The CO(2) released from the reaction was measured by HS-GC. The completion of the reaction was achieved within 25 min at 80 °C when a small sample size (<20 mg) was used. The relative standard deviation (RSD) measurement of precision was less than 4.1%, and the results were within 8.0% of those obtained with the traditional titration for determining the degree of substitution. The present method is simple, practical, automated, and suitable for use in anhydride modified cellulose research., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Abstract: Methyl methacrylate (MMA) was homogeneous-grafted on a cellulose based macro-initiator, cellulose chloroacetyl chloride by the atom transfer radical polymerization (ATRP) at a mild reaction temperature. The synthesized cellulose graft copolymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopies. The linear first-order kinetics of monomer conversion was determined by headspace gas chromatography. The molecular weights and their distributions of the poly (methyl methacrylate) (PMMA) grafted onto the cellulose backbone were determined by gel permeation chromatography. The results confirmed that the generation of the cellulose grafted PMMA at 50°C in the given solvent system was a controlled/living ATRP process. [Copyright &y& Elsevier]

Abstract: This paper reports on a full evaporation headspace gas chromatographic method for rapid determination of monomeric methyl methacrylate (MMA) in the cellulose graft poly-methyl methacrylate (PMMA) via an atom transfer radical polymerization process. The data show that a near-complete mass transfer of MMA from the very small liquid sample size (<30mg) to the vapor phase (headspace) was achieved within 5min at 105°C. The present method has excellent precision (RSD<0.3%) and accuracy (recovery=97%) for the quantification of the residual MMA in cellulose graft PMMA liquid samples. [Copyright &y& Elsevier]