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Abstract  

Pyrolytic process has a promising potential for the environmentally friendly upgrading of lignocellulosic and plastic waste. Thermogravimetry and pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) were used to get information about the reactive decomposition of PCL in binary mixtures with microcrystalline cellulose (MC) or sisal fibres (SF). Preliminary thermogravimetric investigation showed that biomass is thermally degraded at lower temperatures than PCL and this process has a predominant influence on the thermal behaviour of the mixtures. Discrepancies between the experimental and predicted TG/DTG profiles were considered as a measurement of the extent of interactions occurring on co-pyrolysis. It was found that reactivity of PCL was slightly increased in PCL-SF binary mixtures. Evolution of acidic products from cellulose and hemicelluloses decomposition may promote PCL degradation in binary mixtures with SF. It seems that the co-pyrolysis process could have potential for the environmentally friendly transformation of biocomposites.

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Cellulose substituted by organosilicon groups represents a new type of modified cellulose. The silylation changes the physical and chemical properties of cellulose drastically. The thermoanalytical investigation of differently trimethylsilylated cellulose derivatives was carried out under static conditions in air atmosphere. The DTA curves of the cellulose used as starting material are different from those of its silylated derivatives. In the latter a new characteristic exothermic peak appears in the range 320–370°. The value of this maximum depends on the grade of silylation, being shifted towards higher temperatures with higher degrees of substitution.

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The paper reviews the latest achievements in chiral separation by planar chromatography (PC) since 2001. The emphasis is on cellulose derivatives and, especially, microcrystalline cellulose triacetate (MCTA). A comparison is made with HPLC data retrieved from Chirbase. It is shown that TLC has some interesting features compared with HPLC. Some enantiomer separations have been successfully achieved by TLC whereas no data are available for HPLC. For tribenzoyl cellulose derivatives general trends for resolution by both TLC and HPLC are discussed. The last part of the paper discusses reasons for the scarcity of publications on chiral separations by either PC or overpressured layer chromatography (OPLC). The possibilities of PC for chiral separations are rather unexploited.

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Journal of Thermal Analysis and Calorimetry
Authors: Rafael Leite de Oliveira, Hernane da Silva Barud, Rosana M. N. de Assunção, Carla da Silva Meireles, Geandre Oliveira Carvalho, Guimes Rodrigues Filho, Younes Messaddeq, and Sidney José Lima Ribeiro

steps of delignification and bleaching. The material in this condition can be employed in the production of cellulosic derivatives; since for production of these derivatives, cellulose must have the highest purity possible [ 6 ]. The production

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]. Some specific blends of cellulose derivatives with PHAs were studied by Scandola [ 12 ] and Buchanan [ 9 , 13 ]. Scandola noted that the PHB forms miscible blends with the cellulose esters [ 12 ]. On the other hand, Buchanan studied the blends of

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decomposition of pure cellulose and pulp paper. Nada et al . have investigated the thermal behavior of cellulose and some cellulose derivatives. Cullis and co-workers [ 14 ] have blended cigarette paper with various inorganic salts and investigated the effect

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suspending agent should have certain attributes: (1) it should produce a structured vehicle, (2) it should be compatible with other formulation ingredients and (3) it should be nontoxic. Generally used suspending agents in suspension include cellulosic

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-6031(01)00425-7 . 18. Alvarez , VA , Vázquez , A . Thermal degradation of cellulose derivatives/starch blends and sisal fibre biocomposites . Polym Degrad Stabil 2004 84 : 13 – 21 10.1016/j.polymdegradstab.2003

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]. From amongst cellulose derivatives, EC is an ideal polymer for coating modified release (MR) preparations, yet few authors have studied its thermal properties in spite of the fact that more up-to-date preparations to be administered once/twice a day are

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Kinetics of pyrolysis of rice husk . Bioresour Technol 67 : 53 – 59 10.1016/S0960-8524(99)00073-5 . 11. Alvarez , VA , Vázquez , A 2004 Thermal degradation of cellulose derivatives

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