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Recent Scenario of Solid Biopolymer Electrolytes Based Dye-Sensitized Solar Cell
Published in Hieng Kiat Jun, Nanomaterials in Energy Devices, 2017
Rahul Singh, Pramod K. Singh, B. Bhattacharya
Cellulose: Cellulose is the most abundant polymer available worldwide. Cellulose is composed of polymer chains consisting of unbranched β (1→4) linked D-glucopyranosyl units (anhydroglucose unit). Nowadays, there are various procedures for extraction of cellulose microfibrils like pulping methods, acid hydrolysis, steam explosion, etc. Cellulose is attacked by a wide variety of microorganisms (Finkenstadt et al. 2005, Chamy et al. 2013, Dumitriu et al. 1998, Ree et al. 1977). When the samples of HEC (hydroxyethylcellulose) plasticized with glycerol and addition of lithium trifluoromethane sulfonate (LiCF3SO3) salt, the ionic conductivity were obtained in the range of 10−4–10−5 S/cm. The best ionic conductivity obtained was 4.68 × 10−2 S cm−1 at room temperature by using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) doped biopolymer cellulose acetate (CA) matrix in 1-allyl-3-methylimidazolium chloride ([Amim] Cl) (Ramesh et al. 2013).
Manufacturing Methods of PLA Composites
Published in Jyotishkumar Parameswaranpillai, Suchart Siengchin, Nisa V. Salim, Jinu Jacob George, Aiswarya Poulose, Polylactic Acid-Based Nanocellulose and Cellulose Composites, 2022
Guang-Way Bill Jang, Cheng-Han Hsieh, Allen Lai, Sagle Chan
Each anhydroglucose unit (AGU) of cellulose consists of three alcoholic hydroxyl groups, which are accessible for chemical modification reactions. Potential modification reactions for the primary alcohol on C-6 and the secondary alcohol on C-2 as well as C-3 are esterification, etherification as well as oxidation to be carried out in homogeneous or heterogeneous medium. However, due to high crystallinity, there are limited solvents for cellulose materials. Usually, chemical modification of cellulose materials is performed under heterogeneous conditions, and thus the cellulose structure can be maintained to a certain degree. Typical approaches for the chemical modification of cellulose are summarized below.
Hydrothermal Liquefaction A Promising Technology for High Moisture Biomass Conversion
Published in Jaya Shankar Tumuluru, Biomass Preprocessing and Pretreatments for Production of Biofuels, 2018
Ankita Juneja, Deepak Kumar, Jaya Shankar Tumuluru
Cellulose, the most abundant polymer on earth, is made up of a straight chain glucose units linked by β,1-4 glycosidic bonds. Anhydroglucose unit of cellulose contains three free hydroxyl groups that form numerous intra- and inter-molecule hydrogen bonds. Glucose chains bounded by these hydrogen bonds and van der Waal’s forces make a highly crystalline structure which is insoluble in water and resistant to degradation. However, at near critical conditions, cellulose is rapidly hydrolyzed to its constituents. The breaking of the crystalline structure of cellulose under sub- and super-critical conditions is shown as a reaction pathway in Fig. 6.
A detailed study on the rheological behavior of a novel cellulose-based hydrophobically-modified polymer
Published in Petroleum Science and Technology, 2023
Funsho Afolabi, Syed M. Mahmood, Iskandar Dzulkarnain, Donatus Ewere, Saeed Akbari
Out of the numerous cellulose derivatives, sodium cellulose sulfate is one of the least investigated for oil recovery applications. This cellulose derivative is an inorganic ester of cellulose with ꞵ-1-4-glucan as the main chain with the sulfate group replacing the hydroxyl groups at carbon C-2, C-3, and C-6 in the anhydroglucose unit (Muhitdinov et al. 2017). They possess good physicochemical and biological properties because of their solution and micellar properties and thus have found use in the paper and pulp industry, textile industry, medicine, and drug design (Wu, Guan, and Yao 2018). Though they are anionic, they are highly soluble both in organic and polar solvents and of course, they’re biodegradable (Schweiger 1979). Studies have shown sodium cellulose sulfate to have more stable thermal and mechanical properties compared to Carboxymethyl Cellulose (CMC) and Hydroxyethyl Cellulose (HEC) (Schweiger 1979). Without hydrophobic modifications, they have been suggested as thickeners in tertiary oil recovery. From a previous study, sodium cellulose sulfate has been successfully modified hydrophobically using microwave energy-assisted free-radical copolymerization (Afolabi, Mahmood, Johnson, et al. 2022a). See Figure 1 for the molecular structure of the novel cellulose-based polymeric surfactant. From fore-knowledge of qualitative structure-property relationships, it is believed that the inclusion of the hydrophobe and the polyetheroxy functional groups, in combination with the anionic sulfonate group, at the specific locations along the cellulosic backbone should improve the rheological performance and stability of the compound to variable shear rates, and elevated temperature and salinity. In this study, the rheological properties of this novel material will be investigated using reservoir reference conditions of salinity, shear, and temperature. From the understandings garnered from the study, conclusions will be drawn on the feasibility of their applications as viscosifiers and mobility control agents for improved recovery practices.