1
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Katsuhara S, Sunagawa N, Igarashi K, Takeuchi Y, Takahashi K, Yamamoto T, Li F, Tajima K, Isono T, Satoh T. Effect of degree of substitution on the microphase separation and mechanical properties of cellooligosaccharide acetate-based elastomers. Carbohydr Polym 2023; 316:120976. [PMID: 37321706 DOI: 10.1016/j.carbpol.2023.120976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/27/2023] [Accepted: 04/30/2023] [Indexed: 06/17/2023]
Abstract
Thermoplastic elastomers (TPEs) have long been used in a wide range of industries. However, most existing TPEs are petroleum-derived polymers. To realize environmentally benign alternatives to conventional TPEs, cellulose acetate is a promising TPE hard segment because of its sufficient mechanical properties, availability from renewable sources, and biodegradability in natural environments. Because the degree of substitution (DS) of cellulose acetate governs a range of physical properties, it is a useful parameter for designing novel cellulose acetate-based TPEs. In this study, we synthesized cellulose acetate-based ABA-type triblock copolymers (AcCelx-b-PDL-b-AcCelx) containing a celloologosaccharide acetate hard A segment (AcCelx, where x is the DS; x = 3.0, 2.6, and 2.3) and a poly(δ-decanolactone) (PDL) soft B segment. Small-angle X-ray scattering showed that decreasing the DS of AcCelx-b-PDL-b-AcCelx resulted in the formation of a more ordered microphase-separated structure. Owing to the microphase separation of the hard cellulosic and soft PDL segments, all the AcCelx-b-PDL-b-AcCelx samples exhibited elastomer-like properties. Moreover, the decrease in DS improved toughness and suppressed stress relaxation. Furthermore, preliminary biodegradation tests in an aqueous environment revealed that the decrease in DS endowed AcCelx-b-PDL-b-AcCelx with greater biodegradability potential. This work demonstrates the usefulness of cellulose acetate-based TPEs as next-generation sustainable materials.
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Affiliation(s)
- Satoshi Katsuhara
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Naoki Sunagawa
- Department of Biomaterial Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Kiyohiko Igarashi
- Department of Biomaterial Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan; VTT Technical Research Centre of Finland Ltd., VTT FI-02044, Finland
| | - Yutaka Takeuchi
- Noto Center for Fisheries Science and Technology, Faculty of Biological Science and Technology, Kanazawa University, Noto-cho, Ishikawa 927-0552, Japan
| | - Kenji Takahashi
- Faculty of Biological Science and Technology, Institute of Science and Engineering, Kanazawa University, Kanazawa 920-1192, Japan
| | - Takuya Yamamoto
- Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Feng Li
- Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Kenji Tajima
- Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
| | - Takuya Isono
- Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
| | - Toshifumi Satoh
- Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
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KAWAI T, UKITA S, SHIMAMOTO S. Characterization of Chemical Heterogeneity of Cellulose Esters by Gradient Elution HPLC. BUNSEKI KAGAKU 2022. [DOI: 10.2116/bunsekikagaku.71.495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Tadatomo KAWAI
- Department of Applied Chemistry, School of Advanced Engineering, Kogakuin University
| | - Shizuka UKITA
- Production Management Headquarters, DAICEL Corporation
| | - Shu SHIMAMOTO
- Innovation and Business Development Headquarters, DAICEL Corporation
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3
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Acetate differentially regulates IgA reactivity to commensal bacteria. Nature 2021; 595:560-564. [PMID: 34262176 DOI: 10.1038/s41586-021-03727-5] [Citation(s) in RCA: 84] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 06/15/2021] [Indexed: 12/22/2022]
Abstract
The balance between bacterial colonization and its containment in the intestine is indispensable for the symbiotic relationship between humans and their bacteria. One component to maintain homeostasis at the mucosal surfaces is immunoglobulin A (IgA), the most abundant immunoglobulin in mammals1,2. Several studies have revealed important characteristics of poly-reactive IgA3,4, which is produced naturally without commensal bacteria. Considering the dynamic changes within the gut environment, however, it remains uncertain how the commensal-reactive IgA pool is shaped and how such IgA affects the microbial community. Here we show that acetate-one of the major gut microbial metabolites-not only increases the production of IgA in the colon, but also alters the capacity of the IgA pool to bind to specific microorganisms including Enterobacterales. Induction of commensal-reactive IgA and changes in the IgA repertoire by acetate were observed in mice monocolonized with Escherichia coli, which belongs to Enterobacterales, but not with the major commensal Bacteroides thetaiotaomicron, which suggests that acetate directs selective IgA binding to certain microorganisms. Mechanistically, acetate orchestrated the interactions between epithelial and immune cells, induced microbially stimulated CD4 T cells to support T-cell-dependent IgA production and, as a consequence, altered the localization of these bacteria within the colon. Collectively, we identified a role for gut microbial metabolites in the regulation of differential IgA production to maintain mucosal homeostasis.
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4
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Duan L, Liu R, Li Q. A More Efficient Fenton Oxidation Method with High Shear Mixing for the Preparation of Cellulose Nanofibers. STARCH-STARKE 2020. [DOI: 10.1002/star.201900259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Linjuan Duan
- Tianjin Key Laboratory of Pulp & Paper Tianjin University of Science and Technology Tianjin 300457 P. R. China
| | - Rongrong Liu
- Tianjin Key Laboratory of Pulp & Paper Tianjin University of Science and Technology Tianjin 300457 P. R. China
| | - Qun Li
- Tianjin Key Laboratory of Pulp & Paper Tianjin University of Science and Technology Tianjin 300457 P. R. China
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Shibakami M, Sohma M, Kijima N, Nemoto T. Melt spinnabilities of thermoplastic paramylon mixed esters. Heliyon 2019; 5:e02843. [PMID: 31844742 PMCID: PMC6895648 DOI: 10.1016/j.heliyon.2019.e02843] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 07/17/2019] [Accepted: 11/08/2019] [Indexed: 11/30/2022] Open
Abstract
The low thermoplasticities of polysaccharide esters make them unsuitable for melt spinning. In this study, we aimed to overcome this problem by mixed esterification of paramylon, a euglenoid β-1,3-glucan with short- and medium-chain acyl groups, as melt-spinnable materials. Thermal analyses revealed that all the synthesized paramylon mixed esters exhibited glass transition temperatures greater than 100 °C; some of them showed large differences between the melting and 5%-weight-loss temperatures (Td5s) and are extrudable through a spinneret at a temperature ~100 °C below Td5, rendering them potential candidates for the production of melt-spun filaments. Among the various compounds investigated, paramylon acetate propionates, in which the degrees of acetyl- and propionyl-group substitution were 0.5–0.7 and 2.2–2.5, respectively, could be melt-spun to yield mechanically tough crystalline monofilaments. In contrast, the melt spinning of cellulose acetate propionate, analogous to the paramylon acetate propionates in terms of acyl substituents, their substitution degrees, and molecular weights, but differs from it in terms of the glucose linkage mode (i.e., β-1,3 vs β-1,4), yielded brittle, charred, and short filaments. Curdlan acetate propionate, another analogue with a degree of polymerization five times larger than that of paramylon mixed esters, was not extrudable due to the lack of thermoplasticity. Therefore, we herein confirmed the superiority of paramylon as a primary raw material for melt-spun filaments.
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Affiliation(s)
- Motonari Shibakami
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6th, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8566, Japan
| | - Mitsugu Sohma
- Advanced Coating Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Central 5th, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Norihito Kijima
- Advanced Coating Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Central 5th, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Tadashi Nemoto
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6th, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8566, Japan
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6
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Position of acetyl groups on anhydroglucose unit in acetylated starches with intermediate degrees of substitution. Carbohydr Polym 2019; 220:118-125. [DOI: 10.1016/j.carbpol.2019.05.059] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/18/2019] [Accepted: 05/20/2019] [Indexed: 11/20/2022]
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Huang A, Li X, Liang X, Zhang Y, Hu H, Yin Y, Huang Z. Solid-Phase Synthesis of Cellulose Acetate Butyrate as Microsphere Wall Materials for Sustained Release of Emamectin Benzoate. Polymers (Basel) 2018; 10:E1381. [PMID: 30961306 PMCID: PMC6401682 DOI: 10.3390/polym10121381] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/05/2018] [Accepted: 12/10/2018] [Indexed: 12/18/2022] Open
Abstract
Emamectin benzoate (EB), a widely used pesticide, is prone to decomposition by ultraviolet light and suffers from the corresponding loss of efficacy. The timed release of EB based on microspheres is one of the effective methods to solve this issue. As a non-toxic cellulose ester, cellulose acetate butyrate (CAB) is regarded as one of the best wall-forming materials for microcapsules with a good controlled release performance. Herein, two methods-mechanical activation (MA) technology and a conventional liquid phase (LP) method-were employed to synthesize different CABs, namely CAB-MA and CAB-LP, respectively. The molecular structure, rheological property, and thermal stability of these CABs were investigated. The two CABs were used to prepare microspheres for the loading and release of EB via an o/w (oil-in-water) solvent evaporation method. Moreover, the performances such as drug loading, drug entrapment, and anti-photolysis of the drug for these microspheres were studied. The results showed that both CABs were available as wall materials for loading and releasing EB. Compared with CAB-LP, CAB-MA presented a lower molecular weight and a narrower molecular weight distribution. Moreover, the MA method endowed the CAB with more ester substituent groups and less crystalline structure in comparison to the LP method, which had benefits including pelletizing and drug loading.
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Affiliation(s)
- Aimin Huang
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
- Medical College of Guangxi University, Nanning 530004, China.
| | - Xuanhai Li
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
| | - Xingtang Liang
- Qinzhou Key Laboratory of Biowaste Resources for Selenium-Enriched Functional Utilization, College of Petroleum and Chemical Engineering, Qinzhou University, Qinzhou 535011, China.
| | - Yanjuan Zhang
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
| | - Huayu Hu
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
| | - Yanzhen Yin
- Qinzhou Key Laboratory of Biowaste Resources for Selenium-Enriched Functional Utilization, College of Petroleum and Chemical Engineering, Qinzhou University, Qinzhou 535011, China.
| | - Zuqiang Huang
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
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8
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Meng C, Cao GP, Yan YZ, Zhao EY, Hou LY, Shi HY. Synthesis of cellulose acetate propionate with controllable contents and distributions of acetyl and propionyl in the C2, C3 and C6 positions. REACTION KINETICS MECHANISMS AND CATALYSIS 2017. [DOI: 10.1007/s11144-017-1260-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Kono H, Oka C, Kishimoto R, Fujita S. NMR characterization of cellulose acetate: Mole fraction of monomers in cellulose acetate determined from carbonyl carbon resonances. Carbohydr Polym 2017; 170:23-32. [DOI: 10.1016/j.carbpol.2017.04.061] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 04/03/2017] [Accepted: 04/21/2017] [Indexed: 12/19/2022]
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10
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Shirke AN, Butterfoss GL, Saikia R, Basu A, Maria L, Svendsen A, Gross RA. Engineered
Humicola insolens
cutinase for efficient cellulose acetate deacetylation. Biotechnol J 2017; 12. [DOI: 10.1002/biot.201700188] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 05/02/2017] [Accepted: 05/09/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Abhijit N. Shirke
- Department of Chemistry and Chemical Biology Rensselaer Polytechnic Institute Troy NY USA
- Center for Biotechnology and Interdisciplinary Studies Rensselaer Polytechnic Institute Troy NY USA
| | - Glenn L. Butterfoss
- Center for Genomics and Systems Biology New York University Abu Dhabi Abu Dhabi UAE
| | | | | | | | | | - Richard A. Gross
- Department of Chemistry and Chemical Biology Rensselaer Polytechnic Institute Troy NY USA
- Center for Biotechnology and Interdisciplinary Studies Rensselaer Polytechnic Institute Troy NY USA
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11
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Time and energy-efficient homogeneous transesterification of cellulose under mild reaction conditions. Carbohydr Polym 2017; 157:1785-1793. [DOI: 10.1016/j.carbpol.2016.11.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 11/20/2016] [Accepted: 11/21/2016] [Indexed: 11/21/2022]
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12
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Abe M, Sugimura K, Nishio Y. Regioselectivity in Acetylation of Cellulose in Ionic Liquids. ChemistrySelect 2016. [DOI: 10.1002/slct.201600520] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Mitsuru Abe
- Division of Forest and Biomaterials Science; Graduate School of Agriculture; Kyoto University; Sakyo-ku Kyoto 606-8502 Japan
| | - Kazuki Sugimura
- Division of Forest and Biomaterials Science; Graduate School of Agriculture; Kyoto University; Sakyo-ku Kyoto 606-8502 Japan
| | - Yoshiyuki Nishio
- Division of Forest and Biomaterials Science; Graduate School of Agriculture; Kyoto University; Sakyo-ku Kyoto 606-8502 Japan
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13
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Synthesis and enzymatic degradation of randomly substituted 2,3,6-O-cellulose acetate and regioselectively substituted 2,3-O-cellulose acetate. Polym Degrad Stab 2016. [DOI: 10.1016/j.polymdegradstab.2016.04.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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NMR characterization of cellulose acetate: Chemical shift assignments, substituent effects, and chemical shift additivity. Carbohydr Polym 2015; 118:91-100. [DOI: 10.1016/j.carbpol.2014.11.004] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 10/24/2014] [Accepted: 11/08/2014] [Indexed: 11/19/2022]
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15
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von Schantz L, Schagerlöf H, Nordberg Karlsson E, Ohlin M. Characterization of the substitution pattern of cellulose derivatives using carbohydrate-binding modules. BMC Biotechnol 2014; 14:113. [PMID: 25540113 PMCID: PMC4302574 DOI: 10.1186/s12896-014-0113-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 12/18/2014] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Derivatized celluloses, such as methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC), are of pharmaceutical importance and extensively employed in tablet matrices. Each batch of derivatized cellulose is thoroughly characterized before utilized in tablet formulations as batch-to-batch differences can affect drug release. The substitution pattern of the derivatized cellulose polymers, i.e. the mode on which the substituent groups are dispersed along the cellulose backbone, can vary from batch-to-batch and is a factor that can influence drug release. RESULTS In the present study an analytical approach for the characterization of the substitution pattern of derivatized celluloses is presented, which is based on the use of carbohydrate-binding modules (CBMs) and affinity electrophoresis. CBM4-2 from Rhodothermus marinus xylanase 10A is capable of distinguishing between batches of derivatized cellulose with different substitution patterns. This is demonstrated by a higher migration retardation of the CBM in acrylamide gels containing batches of MC and HPMC with a more heterogeneous distribution pattern. CONCLUSIONS We conclude that CBMs have the potential to characterize the substitution pattern of cellulose derivatives and anticipate that with use of CBMs with a very selective recognition capacity it will be possible to more extensively characterize and standardize important carbohydrates used for instance in tablet formulation.
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16
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Synthesis and characterization of neutral and anionic cellulosic amphiphiles. Carbohydr Polym 2014; 113:480-9. [DOI: 10.1016/j.carbpol.2014.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2014] [Revised: 07/01/2014] [Accepted: 07/03/2014] [Indexed: 11/20/2022]
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17
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Thermoplasticization of euglenoid β-1,3-glucans by mixed esterification. Carbohydr Polym 2014; 105:90-6. [PMID: 24708957 DOI: 10.1016/j.carbpol.2014.01.053] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 12/28/2013] [Accepted: 01/14/2014] [Indexed: 11/21/2022]
Abstract
We experimentally demonstrated that paramylon, a storage polysaccharide of Euglena gracilis, is efficiently thermoplasticized by adding acyl groups that differ in alkyl chain length. Glass transition temperature of mixed paramylon esters was higher than those of plant-based polylactic acid (PLA), poly 11-aminoundecanoic acid (PA11), and petroleum-based acrylonitrile-butadiene-styrene (ABS) resin and was comparable to that of cellulose acetate stearate (CAS). Their thermoplasticity was equivalent to or higher than those of these reference plastics. The bending strength and bending elastic modulus of injection molded test specimens made from mixed paramylon esters were comparable to those of the reference plastics. While their impact strength was lower than that of specimens made from ABS resin and CAS, it was comparable to those of PLA and PA11. Euglenoid β-1,3-glucans are thus a potential component of thermoplastic materials.
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Sugimura K, Teramoto Y, Nishio Y. Blend miscibility of cellulose propionate with poly(N-vinyl pyrrolidone-co-methyl methacrylate). Carbohydr Polym 2013; 98:532-41. [PMID: 23987378 DOI: 10.1016/j.carbpol.2013.06.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 05/15/2013] [Accepted: 06/22/2013] [Indexed: 11/18/2022]
Abstract
The blend miscibility of cellulose propionate (CP) with poly(N-vinyl pyrrolidone-co-methyl methacrylate) (P(VP-co-MMA)) was investigated. The degree of substitution (DS) of CP used ranged from 1.6 to >2.9, and samples for the vinyl polymer component were prepared in a full range of VP:MMA compositions. Through DSC analysis and solid-state (13)C NMR and FT-IR measurements, we revealed that CPs of DS<2.7 were miscible with P(VP-co-MMA)s of VP≥~10mol% on a scale within a few nanometers, in virtue of hydrogen-bonding interactions between CP-hydroxyls and VP-carbonyls. When the DS of CP exceeded 2.7, the miscibility was restricted to the polymer pairs using P(VP-co-MMA)s of VP=ca. 10-40 mol%; the scale of mixing in the blends concerned was somewhat larger (ca. 5-20 nm), however. The appearance of such a "miscibility window" was interpretable as an effect of intramolecular repulsion in the copolymer component. Results of DMA and birefringence measurements indicated that the miscible blending of CP with the vinyl polymer invited synergistic improvements in thermomechanical and optical properties of the respective constituent polymers. Additionally, it was found that the VP:MMA composition range corresponding to the miscibility window was expanded by modification of the CP component into cellulose acetate propionate.
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Affiliation(s)
- Kazuki Sugimura
- Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
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19
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Chang C, Teramoto Y, Nishio Y. Synthesis of O
-(2,3-dihydroxypropyl) cellulose in NaOH/urea aqueous solution: As a precursor for introducing “necklace-like” structure. ACTA ACUST UNITED AC 2013. [DOI: 10.1002/pola.26773] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Chunyu Chang
- Division of Forest and Biomaterials Science; Graduate School of Agriculture; Kyoto University; Sakyo-ku Kyoto 606-8502 Japan
- Guangzhou Sugarcane Industry Research Institute; Guangzhou 510316 China
| | - Yoshikuni Teramoto
- Division of Forest and Biomaterials Science; Graduate School of Agriculture; Kyoto University; Sakyo-ku Kyoto 606-8502 Japan
| | - Yoshiyuki Nishio
- Division of Forest and Biomaterials Science; Graduate School of Agriculture; Kyoto University; Sakyo-ku Kyoto 606-8502 Japan
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20
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Shibakami M, Tsubouchi G, Nakamura M, Hayashi M. Preparation of carboxylic acid-bearing polysaccharide nanofiber made from euglenoid β-1,3-glucans. Carbohydr Polym 2013; 98:95-101. [PMID: 23987321 DOI: 10.1016/j.carbpol.2013.05.026] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 05/11/2013] [Accepted: 05/14/2013] [Indexed: 11/19/2022]
Abstract
This paper introduces a new strategy for creating surface modified polysaccharide nanofibers. To demonstrate proof of principle, the synthesis, structure, and self-assembly behavior of a carboxylic acid-bearing polysaccharide made from paramylon (β-1,3-glucan) and succinic anhydride were investigated. Examination by a combination of NMR, FT-IR, and SEC-MALLS confirmed that successful preparation of the desired succinylated paramylon without significant depolymerization. NMR, SEC-MALLS, visible absorption and CD spectroscopic analyses indicated that the paramylon derivative forms the triplex structure in solutions. SEM observation revealed that succinylated paramylon forms a nanofiber that has carboxylic acid on the surface.
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Affiliation(s)
- Motonari Shibakami
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6th, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
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22
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Tanaka S, Honzawa H, Iji M. Development of cardanol-bonded cellulose thermoplastics: High productivity achieved by using isocyanate-modified cardanol. J Appl Polym Sci 2013. [DOI: 10.1002/app.39313] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Shukichi Tanaka
- Smart Energy Research Laboratories; NEC Corporation; 34 Miyukigaoka; Tsukuba; Ibaraki; 305-8501; Japan
| | - Hideki Honzawa
- Friction Materials Department; Tohoku Chemical Industries, Ltd.; 1200 Fujita; Nasukarasuyama; Tochigi; 321-0532; Japan
| | - Masatoshi Iji
- Smart Energy Research Laboratories; NEC Corporation; 34 Miyukigaoka; Tsukuba; Ibaraki; 305-8501; Japan
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23
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Yang D, Kumar V. Preparation and characterization of novel oxidized cellulose acetate methyl esters. Carbohydr Polym 2012; 90:1486-93. [DOI: 10.1016/j.carbpol.2012.07.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 06/13/2012] [Accepted: 07/06/2012] [Indexed: 11/28/2022]
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Huang K, Wang B, Cao Y, Li H, Wang J, Lin W, Mu C, Liao D. Homogeneous preparation of cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB) from sugarcane bagasse cellulose in ionic liquid. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:5376-5381. [PMID: 21452895 DOI: 10.1021/jf104881f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Cellulose acetate butyrate (CAB) and cellulose acetate propionate (CAP) were prepared homogeneously in a 1-allyl-3-methylimidazolium chloride (AmimCl) ionic liquid system from sugarcane bagasse (SB). The reaction temperature, reaction time, and molar ratio of butyric (propionic) anhydride/anhydroglucose units in the cellulose affect the butyryl (B) or propionyl (P) content of CAB or CAP samples. The (13)C NMR data revealed the distribution of the substituents of CAB and CAP. The thermal stability of sugar cane bagasse cellulose was found by thermogravimetric analysis to have decreased after chemical modification. After reaction, the ionic liquid was effectively recycled and reused. This study provides a new way for high-value-added utilization of SB and realizing the objective of turning waste into wealth.
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Affiliation(s)
- Kelin Huang
- School of Materials Science and Engineering, Beijing University of Technology, Beijing, China
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Abstract
Starch and cellulose are the most abundant and important representatives of renewable biomass. Since the mid-19th century their properties have been changed by chemical modification for commercial and scientific purposes, and there substituted polymers have found a wide range of applications. However, the inherent polydispersity and supramolecular organization of starch and cellulose cause the products resulting from their modification to display high complexity. Chemical composition analysis of these mixtures is therefore a challenging task. Detailed knowledge on substitution patterns is fundamental for understanding structure-property relationships in modified cellulose and starch, and thus also for the improvement of reproducibility and rational design of properties. Substitution patterns resulting from kinetically or thermodynamically controlled reactions show certain preferences for the three available hydroxyl functions in (1→4)-linked glucans. Spurlin, seventy years ago, was the first to describe this in an idealized model, and nowadays this model has been extended and related to the next hierarchical levels, namely, the substituent distribution in and over the polymer chains. This structural complexity, with its implications for data interpretation, and the analytical approaches developed for its investigation are outlined in this article. Strategies and methods for the determination of the average degree of substitution (DS), monomer composition, and substitution patterns at the polymer level are presented and discussed with respect to their limitations and interpretability. Nuclear magnetic resonance spectroscopy, chromatography, capillary electrophoresis, and modern mass spectrometry (MS), including tandem MS, are the main instrumental techniques employed, in combination with appropriate sample preparation by chemical and enzymatic methods.
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Billy M, Da Costa AR, Lochon P, Clément R, Dresch M, Etienne S, Hiver J, David L, Jonquières A. Cellulose acetate graft copolymers with nano-structured architectures: Synthesis and characterization. Eur Polym J 2010. [DOI: 10.1016/j.eurpolymj.2010.01.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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THE SURFACE MODIFICATION OF NANOCRYSTALLINE CELLULOSE. ACTA POLYM SIN 2010. [DOI: 10.3724/sp.j.1105.2006.00982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Chen B, Zhong L, Gu L. Thermal properties and chemical changes in blend melt spinning of cellulose acetate butyrate and a novel cationic dyeable copolyester. J Appl Polym Sci 2010. [DOI: 10.1002/app.30984] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tan Y, Hu A, Xia L, You T, Cao J. Synthesis and application of CDA-beta-CD in controlling release of drug. J Appl Polym Sci 2009. [DOI: 10.1002/app.30189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Adden R, Melander C, Brinkmalm G, Knarr M, Engelhardt J, Mischnick P. The Applicability of Enzymes in Cellulose Ether Analysis. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/masy.200950605] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hornig S, Heinze T. Efficient approach to design stable water-dispersible nanoparticles of hydrophobic cellulose esters. Biomacromolecules 2008; 9:1487-92. [PMID: 18393524 DOI: 10.1021/bm8000155] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Commercially prepared cellulose acetate, cellulose acetate propionate, -butyrate, and -phthalate as well as cellulose acetates prepared in the laboratory scale with varying degree of substitution (DS) self-assemble into regular nanoparticles, ranging in size from 86 to 368 nm, by using two different techniques of nanoprecipitation. Dialysis of polymers dissolved in N,N-dimethylacetamide results in the formation of regular nanospheres whereas the preparation in acetone by successive adding of water leads to bean-shaped particles in the nanoscale. One criterion for nanoprecipitation is the existence of dilute polymer solutions. Furthermore, the formation of nanoparticles strongly depends on DS and distribution of the substituents. Concerning this issue, quantitative (13)C NMR spectroscopy was applied for detailed structure characterization of selected cellulose acetates. The stability of the nanoparticle suspensions in the physiological pH range was observed by zeta potential measurements.
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Affiliation(s)
- Stephanie Hornig
- Center of Excellence for Polysaccharide Research, Friedrich Schiller University of Jena, D-07743 Jena, Germany
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Aoki D, Teramoto Y, Nishio Y. SH-Containing Cellulose Acetate Derivatives: Preparation and Characterization as a Shape Memory-Recovery Material. Biomacromolecules 2007; 8:3749-57. [DOI: 10.1021/bm7006828] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dan Aoki
- Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yoshikuni Teramoto
- Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yoshiyuki Nishio
- Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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Adden R, Müller R, Brinkmalm G, Ehrler R, Mischnick P. Comprehensive Analysis of the Substituent Distribution in Hydroxyethyl Celluloses by Quantitative MALDI-ToF-MS. Macromol Biosci 2006; 6:435-44. [PMID: 16761275 DOI: 10.1002/mabi.200600028] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Three HECs with a high MS (HEC 1: 1.89, HEC 2: 1.94, HEC 3: 3.03) were analyzed with respect to their substituent distribution and tandem reaction in the glucosyl unit by GLC of the corresponding glucitol acetates, and along the polymer chain by MALDI-ToF-MS after a multi-step sample preparation. For comparison of the experimental data with a random pattern an extended Bernoulli plot was applied to calculate a random distribution for the composition of un-, mono-, di-, tri-, and up to heptasubstituted glucosyl units (c0, c1, c2, ... c7).
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Affiliation(s)
- Roland Adden
- TU Braunschweig, Institut für Lebensmittelchemie, Schleinitzstr. 20, D-38106 Braunschweig, Germany
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Tsunashima Y, Ikuno M, Onodera G, Horii F. Low-temperature dynamic light scattering. I. Structural reorganization and physical gel formation in cellulose triacetate/methyl acetate dilute solution at -99 - 45 degrees C. Biopolymers 2006; 82:222-33. [PMID: 16479588 DOI: 10.1002/bip.20479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Curious low-temperature solubility of cellulose triacetates (CTA; here we use nominally "CTA," but the sample still contains 7% of C-6 position hydroxyls) in an organic solvent, methyl acetate (MA), was studied by a newly designed low-temperature type of DLS apparatus, which enabled for the first time to investigate the structural change of CTA in solution from 45 degrees C down to -100 degrees C. A molecularly dissolved CTA was found to coexist with three types of self-assemblies over all the temperature ranges except for the three specific temperatures T* of 30, -10, and -75 degrees C. However, these multiple self-assemblies are not in real thermodynamic equilibrium but in a metastable state, which could be stabilized effectively by the intermolecular hydrogen bonding (HB) with the help of the dipole interaction at low temperatures. In more detail, with decreasing temperature, these assemblies performed the structural reorganization drastically at three T*'s and would finally be frozen in a physical gel structure at -99 degrees C; around the freezing temperature of MA, CTA molecules could be trapped homogeneously in the frozen MA. The crucial role in such structural reorganizations is played by the balance between the intermolecular HB and the dipole interaction worked in the highly electronegative solvent. Because these interactions, which are mediated by the solvent electronegativity, change drastically with temperature, they result in the control of not only the single CTA chain conformation (= the intramolecular HB) but also the binding ways of the intermolecular HBs between CTA molecules and they induce multitudinous metastable structures in solution. Here it is noted that HB could work mainly between the C-6 position hydroxyls in the anhydroglucose units of CTA and are essentially effective at low temperatures.
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Adden R, Müller R, Mischnick P. Fractionation of Methyl Cellulose According to Polarity – a Tool to Differentiate First and Second Order Heterogeneity of the Substituent Distribution. MACROMOL CHEM PHYS 2006. [DOI: 10.1002/macp.200600048] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Adden R, Melander C, Brinkmalm G, Gorton L, Mischnick P. New Approaches to the Analysis of Enzymatically Hydrolyzed Methyl Cellulose. Part 1. Investigation of the Influence of Structural Parameters on the Extent of Degradation. Biomacromolecules 2006; 7:1399-409. [PMID: 16677020 DOI: 10.1021/bm050941+] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Six methyl celluloses (MCs), one with a degree of substitution (DS) of 1.32 and five with DS between 1.83 and 1.88, were thoroughly investigated. Monomer composition and methyl distribution in the polymer chain were analyzed after total or partial random hydrolysis and appropriate derivatization with gas chromatography (GC) and mass spectrometry (MS), respectively, and used as reference data. The same MCs were then hydrolyzed with an enzyme preparation of Trichoderma longibrachiatum and further investigated with size-exclusion chromatography with multiangle light scattering and refractive index detection (SEC-MALS/RI) and MS. Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) in combination with various MS analyzers were compared with respect to quantification of the degradation products directly and after perdeuteriomethylation. The methyl group distribution in the oligomeric fractions and the average DS as a function of chain length were calculated from ESI mass spectra. With help of the reference analysis, patterns could be corrected for the unspecific contribution of end groups. By labeling and ESI tandem MS, our knowledge about the tolerance of the enzymes' sub-sites with respect to the number of methyl groups could be improved.
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Affiliation(s)
- Roland Adden
- TU Braunschweig, Institut für Lebensmittelchemie, Schleinitzstr. 20, D-38106 Braunschweig, Germany
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Melander C, Adden R, Brinkmalm G, Gorton L, Mischnick P. New Approaches to the Analysis of Enzymatically Hydrolyzed Methyl Cellulose. Part 2. Comparison of Various Enzyme Preparations. Biomacromolecules 2006; 7:1410-21. [PMID: 16677021 DOI: 10.1021/bm0509422] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this part of our studies, dealing with new approaches to the analysis of enzymatically hydrolyzed methyl cellulose, five different enzymes or enzyme preparations containing endoglucanases (from Bacillus agaradhaerens Cel 5A, Trichoderma reesei, Trichoderma viride, and two obtained from Trichoderma longibrachiatum) were used to hydrolyze six different methyl celluloses (MCs). The main goal was to investigate whether enzymes could be used for determination of the heterogeneity of the substituent distribution along the cellulose chain. To obtain information about the heterogeneity, it was necessary to gather information on how the enzymes affect hydrolysis. Size exclusion chromatography with multi-angle light scattering and refractive index detection (SEC-MALS/RI) was used to estimate the molar mass distribution of the MCs before and after hydrolysis. A novel internal standard addition method in combination with electrospray ionization ion trap mass spectrometry (ESI-ITMS) was used to determine the amount of formed oligomers. Two MCs, one with a degree of substitution (DS) of 1.8 and one with DS 1.3, were hydrolyzed with all of the five enzymes. The yield of summarized di- and trisaccharides was approximately 2% of the hydrolysis products for the MC with DS 1.8, whereas the product mixture, obtained from a MC with a DS of 1.3, contained 7-16% di- and trisaccharides. By a novel sample preparation method in combination with ESI-IT tandem MS, outlined in part 1 of this work, it was shown that the enzymes produced oligomers with the reducing end bearing no or only one substituent. Comparison of the methyl pattern at the nonreducing ends of the dimers and trimers indicated that the -2 subsite of the active complex is less tolerant than subsites -3 and +1. All enzymes had similar general selectivity toward the methyl substituents but also showed some differences. From both SEC-MALS/RI and ESI-ITMS, differences with respect to substituent distribution of MCs could be recognized but not for each enzyme used. Basic considerations for enzymatic hydrolysis and analysis of methyl cellulose were listed as a consequence of the results from the work.
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Affiliation(s)
- Claes Melander
- Department of Analytical Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
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Adden R, Niedner W, Müller R, Mischnick P. Comprehensive Analysis of the Substituent Distribution in the Glucosyl Units and along the Polymer Chain of Hydroxyethylmethyl Celluloses and Statistical Evaluation. Anal Chem 2006; 78:1146-57. [PMID: 16478106 DOI: 10.1021/ac051484q] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydroxyethylmethyl celluloses (HEMC, DS(Me) 1.46-1.66, DS(HE) = 0.14-0.17) have been analyzed with respect to their methyl and hydroxyethyl pattern in the glucosyl units and along the polymer chain. Methyl groups were located by GLC/MS after direct hydrolysis, reduction, and acetylation, and the distribution of hydroxyethyl residues in the glucosyl units could be determined with enhanced sensitivity after permethylation to unify a certain HE pattern occurring in combination with various methyl patterns in a single peak. To get insight into the distribution of Me and HE along the cellulose chain, a method was developed which overcomes the strong discrimination of relative ion intensities caused by hydroxyalkyl groups and enables quantitative determination of the oligomer composition after random degradation for the first time. This comprises perdeuteriomethylation; partial acid hydrolysis; reductive amination with propylamine; and, finally, permethylation to yield completely O- and N-alkylated, permanently charged oligosaccharides. Although the methyl pattern can be determined by electrospray ionization ion-trap mass spectrometry (ESI-IT-MS) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), as well, only MALDI-TOF-MS produced representative data for a quantitative evaluation of the HE pattern. Distribution of HE groups matches with a random distribution calculated from the monomer composition, whereas the methyl pattern was heterogeneous to a different extent.
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Affiliation(s)
- Roland Adden
- TU Braunschweig, Institut für Lebensmittelchemie, Schleinitzstrasse 20, D-38106 Braunschweig, Germany
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Preparation of polymer brush-type cellulose β-ketoesters using LiCl/1,3-dimethyl-2-imidazolidinone as a solvent. POLYMER 2005. [DOI: 10.1016/j.polymer.2005.01.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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42
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Xiao D, Hu J, Zhang M, Li M, Wang G, Yao H. Synthesis and characterization of camphorsulfonyl acetate of cellulose. Carbohydr Res 2004; 339:1925-31. [PMID: 15261585 DOI: 10.1016/j.carres.2004.06.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2004] [Revised: 05/23/2004] [Accepted: 06/13/2004] [Indexed: 11/20/2022]
Abstract
Novel cellulose derivatives were prepared from reacting (1R)-(+)-camphor-10-sulfonic chloride (CSC) with cellulose acetate (CA) in acetone and triethylamine. The reaction conditions, including reaction time and reactant molar ratios, were optimized. The structure of the products was confirmed by means of 1H NMR, 13C NMR, FT-IR and elementary analysis. The techniques were also used to determine the degree of the substitution of camphorsulfonyl groups (DSCS). The data calculated from 1H NMR, 13C NMR, percent grafting (G %) and elementary analysis coincided with those from chemical analysis. Compared to cellulose acetate, the cellulose derivatives exhibited decreased thermal stability, improved solubility in organic solvents and enhanced enantioselectivity towards tyrosine isomers. The solubility and enantioselectivity increased with increasing degrees of camphorsulfonyl substitution.
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Affiliation(s)
- Dingshu Xiao
- Key Laboratory of Polymer Materials for Electronics of Guangdong Province, Guangzhou Institute of Chemistry, Polymer Science, Chinese Academy of Sciences, Guangzhou Wushan Leyiju 1122, Guangzhou 510650, PR China
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Richardson S, Gorton L. Characterisation of the substituent distribution in starch and cellulose derivatives. Anal Chim Acta 2003. [DOI: 10.1016/j.aca.2003.08.005] [Citation(s) in RCA: 139] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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44
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Einfeldt J, Kwasniewski A, Klemm D, Dicke R, Einfeldt L. Analysis of side group motion in O -acetyl-starch using regioselective 2- O -acetyl-starches by means of dielectric spectroscopy. POLYMER 2000. [DOI: 10.1016/s0032-3861(00)00305-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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45
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Tsunashima Y, Hattori K. Substituent Distribution in Cellulose Acetates: Its Control and the Effect on Structure Formation in Solution. J Colloid Interface Sci 2000; 228:279-286. [PMID: 10926467 DOI: 10.1006/jcis.2000.6952] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Architecture-regulated cellulose derivatives were prepared by regioselective substitution of C-2, -3, and -6 position hydroxyls in cellulose by O-acetyls or trityls. Their dynamic structures formed in polar solvents were compared with those by the commercial cellulose acetates where the distribution of hydroxyls and O-acetyls was nearly random in the chain. It was found that the difference in the chain architecture induces a large difference in the chain conformation, the solubility, and the clustering mechanism and structures; i.e., they changed with solvent quality, concentration, temperature, strength of external field, and so on. Copyright 2000 Academic Press.
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Affiliation(s)
- Y Tsunashima
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
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46
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Tezuka Y. Pullulan nonaacetate: Assignment of chemical shifts of the acetyl protons and acetyl carbonyl carbons by 2D-NMR spectroscopy. Carbohydr Res 1997. [DOI: 10.1016/s0008-6215(97)10036-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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47
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Falk H, Stanek M, Wutka R. Structural Aspects of Partially Acetylated Degraded Amylopectins — A13C NMR Study. STARCH-STARKE 1997. [DOI: 10.1002/star.19970491205] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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48
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Tezuka Y, Tsuchiya Y, Shiomi T. 13C NMR determination of substituent distribution in carboxymethylcellulose by use of its peresterified derivatives. Carbohydr Res 1996. [DOI: 10.1016/s0008-6215(96)00163-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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49
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Falk H, Micura R, Stanek M, Wutka R. Structural Aspects of Native and Acid or Enzyme Degraded Amylopectins - a13C NMR Study. STARCH-STARKE 1996. [DOI: 10.1002/star.19960480908] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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