Swelling behaviour of cellulose by chemical and mechanical treatments.

Isogai, Akira; Onabe, Fumihiko; Usuda, Makoto

doi:10.2115/fiber.48.9_487

Cited by 9 publications

(4 citation statements)

References 5 publications

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“…The swelling rate of SFC increases with a coefficient of 1.30 from pH 6.5 to 13.5. This is because cellulosic fibers swell in alkaline media (41) and/or because the ionization of proteins increases their hydration at alkaline pH. As for partially crystalline polymers, the swelling rate of SFC is limited.…”

Section: Sunflower Materials Composition Sfc Compositionmentioning

confidence: 99%

Sunflower Cake as a Natural Composite: Composition and Plastic Properties

Geneau-Sbartaï

Leyris

Silvestre

et al. 2008

J. Agric. Food Chem.

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Nowadays, the end-of-life of plastic products and the decrease of fossil energy are great environmental problems. Moreover, with the increase of food and nonfood transformations of renewable resources, the quantities of agro-industrial byproducts and wastes increase hugely. These facts allow the development of plastic substitutes made from agro-resources. Many researches show the feasibility of molding biopolymers extracted from plants like a common polymeric matrix. Other natural macromolecules are used like fillers into polyolefins, for example. However, limited works present results about the transformation of a natural blend of biopolymers into a plastic material. The aim of this study is the determination of the composition of sunflower cake (SFC) and also the characterization of its components. These were identified by chemical and biochemical analysis often used in agricultural or food chemistry. Most of the extraction and purification processes modify the macrostructure of several biopolymers (e.g., denaturation of proteins, cleavage or creation of weak bonds, etc.). So, the composition of different parts of the sunflower seed (husk, kernel, and also protein isolate) was determined, and the plasticlike properties of their components were studied with thermogravimetric analysis, differential scanning calorimetry, and a dynamic mechanical thermal analysis apparatus. Finally, this indirect way of characterization showed that SFC can be considered a natural composite. In SFC, several components like lignocellulosic fibers [40%/dry matter (DM)], which essentially come from the husk of sunflower seed, can act as fillers. However, other biopolymers like globulins ( approximately 30% of the 30% of sunflower seed proteins/DM of SFC) can be shaped as a thermoplastic-like material because this kind of protein has a temperature of glass transition and a temperature of denaturation that seems to be similar to a melting temperature. These proteins have also viscoelastic properties. Moreover, SFC has similar rheological properties and other physicochemical properties compatible with shaping or molding behaviors of plastic-processing machinery.

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Section: Sunflower Materials Composition Sfc Compositionmentioning

confidence: 99%

Sunflower Cake as a Natural Composite: Composition and Plastic Properties

Geneau-Sbartaï

Leyris

Silvestre

et al. 2008

J. Agric. Food Chem.

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“…Swelling is an important physicochemical characteristic of sunflower oil cake. It has been found that the swelling of sunflower oil cake increases with an increase in the alkalinity of the solution due to the increase in the cellulose fiber volume and the ionization of proteins in the alkaline environment (Isogai et al, 1992). When the temperature increases from 50 °C to 150 °C, the mass loss of sunflower oil cake occurs due to the dehydration of its components.…”

Section: Resultsmentioning

confidence: 99%

Effect of process parameters on biopolymer films based on sunflower oil cake

Šuput¹,

Lazić²,

Popović³

et al. 2018

J Proc Ener Agri

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The purpose of this paper is the synthesis and characterization of biodegradable composite films based on whole sunflower oil cake, as well as the effect of process parameters (pH and temperature)on the film properties obtained. Films were synthesized at different temperatures (room temperature, 60 °C and 90 °C) and pH values (10 and 12). The film samples obtained were characterized by the mechanical, barrier and physicochemical properties determination. The experimental results showed that the tensile strength values increased with temperature and pH value increments, whereas the sample with the highest elongation at break value was 60 °C/pH12. The water vapour permeability values were uniform (8.62 g/m 2 h-11.63 g/m 2 h), and lower values were recorded in samples synthesized at higher temperatures. The results obtained relative to light transmission were uniform, and the maximum transmission value was reached at 800 nm (24.1-35.7 %). The values obtained for swelling and solubility parameters are characteristic of the nature of biopolymer films.

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“…This tends to increase the reactive surface area of the cellulose pulp, thus enhancing the accessibility of the cellulose (Krässig 1993). Several other studies in the area of mechanical treatment reported using a combination of mechanical treatments with other treatments (Isogai et al 1992;Zhao et al 2006).…”

Section: Introductionmentioning

confidence: 99%

Carboxymethylated pulp as starting point to prepare hydroxypropylmethyl cellulose with enhanced gel rheological properties in an aqueous medium

Hamed

Al-Kerm

et al. 2021

BioRes

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Hydroxypropyl methylcellulose in an aqueous solution upon heating tends to undergo thermal gelation, where the polymer chains form a network and precipitate from solution. This occurs at a temperature known as thermal gelation point. Polymer precipitation causes a significant drop in the shear viscosity. This could be a disadvantage in a hot environment or in applications were heat is applied. In this work, a hydroxypropylmethyl cellulose (HPMC) was formed that undergoes thermal gelation with no polymer precipitation and with enhanced rheological properties. The target HPMC was prepared from wood pulp with a low content of carboxymethyl groups. The produced hydroxypropyl methylcellulose (CMHPMC) derivative showed unique physical properties that are not achievable with typical hydroxypropyl methylcellulose. The thermal gelation temperature of an aqueous solution of CMHPMC was increased from 55 °C for commercial HPMC to 85 °C for CMHPMC. A substitution level of carboxymethylation that led to an HPMC with a thermal gelation and with no precipitation was determined to be a 0.15 of carboxyl groups per anhydroglucose repeat unit. In addition, the carboxymethylated pulp showed an enhanced reactivity towards etherification reactions.

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Swelling behaviour of cellulose by chemical and mechanical treatments.

Cited by 9 publications

References 5 publications

Sunflower Cake as a Natural Composite: Composition and Plastic Properties

Sunflower Cake as a Natural Composite: Composition and Plastic Properties

Effect of process parameters on biopolymer films based on sunflower oil cake

Carboxymethylated pulp as starting point to prepare hydroxypropylmethyl cellulose with enhanced gel rheological properties in an aqueous medium

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