PROSPECTS OF CELLULOSE NITRATES FROM UNCONVENTIONAL FEEDSTOCKS FOR USE IN COMPOSITE EX-PLOSIVES

Research on the synthesis of in-demand industrial-grade cellulose nitrates from unconventional feedstocks such as Miscanthus, oat hulls, intermediate flax straw is of the most immediate interest due to a lack of national cotton and to encountered problems with wood cellulose. The celluloses derived herein from the said unconventional feedstocks are inhomogeneous in nature, are composed mostly of short fibers, and have non-cellulosic constituents as opposed to elite cotton – these all pose certain difficulties in developing such a nitrocellulose production technology. Besides, it is worth noting that cellulosic fibers of the said feedstocks are peculiar in nature on their own. The findings obtained herein suggest that the research problem can successfully be solved. The pulp samples obtained in this study from the unconventional biomasses by the nitric-acid process have 85−95% α-cellulose and 580−1420 degree of polymerization. These specimens similar in properties to industrial Colloxylin were obtained under optimal synthetic conditions for highly soluble cellulose nitrates by using commercial mixed acid: 11.97–12.29% N, 8–15 mPa∙s, and 98% solubility in alcohol–ester mixture. The morphological features of the resultant cellulose nitrates were characterized by scanning electron microscopy. Infrared spectroscopy revealed the intrinsic frequencies (2560–2550, 1670–1660, 1650–1620, 1280–1270, 830–810, 750–740, 680–670 cm-1) that identify the resultant products as cellulose nitroesters. The practical importance of this research is that the nitrocelluloses obtained from the unconventional non-woody feedstocks can be used as the promising component in the manufacture of explosive formulations.

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Oat-hull cellulose nitrates for explosive compositions

Доклады Академии наук ◽

10.31857/s0869-56524874391-395 ◽

2019 ◽

Vol 487 (4) ◽

pp. 391-395

Author(s):

G. V. Sakovich ◽

V. V. Budaeva ◽

А. А. Korchagina ◽

Yu. А. Gismatulina ◽

N. V. Kozyrev ◽

...

Keyword(s):

High Viscosity ◽

Scanning Calorimetry ◽

High Chemical ◽

Oat Hulls ◽

Mixed Acid ◽

Chemical Structures ◽

Chemical Purity ◽

Cellulose Nitrates ◽

Composite Explosives ◽

High Chemical Stability

Cellulose nitrates similar in basic properties to high-viscosity lacquer-grade Colloxyline were synthesized by esterification of pulp with mixed acid. The pulp was isolated from the easily renewable domestic feedstock - oat hulls - the agro-industrial waste. The cellulose nitrate test samples were comparatively evaluated. Infrared and 13C NMR spectroscopies confirmed the chemical structures were identical. It was established by differentiated scanning calorimetry and ampule chromatography that the samples had a high chemical purity. The cellulose nitrates were found to have satisfactory impact and friction sensitivities of 50 mm and 1200 kgf/cm2 and exhibit a good chemical compatibility and a high chemical stability when blended with plasticizers. The findings suggest that it is advisable to use oat-hull cellulose nitrates as the component of composite explosives.

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Highly soluble cellulose nitrates from unconventional feedstocks

MATEC Web of Conferences ◽

10.1051/matecconf/201824300005 ◽

2018 ◽

Vol 243 ◽

pp. 00005

Author(s):

Yulia Gismatulina ◽

Anna Korchagina ◽

Vera Budaeva ◽

Gennady Sakovich

Keyword(s):

Chemical Shifts ◽

Temperature Treatment ◽

Exothermic Peak ◽

High Temperature Treatment ◽

Absorption Bands ◽

Oat Hulls ◽

Mixed Acid ◽

Nitration Product ◽

Cellulose Nitrates ◽

C Nmr

Celluloses isolated by the nitric-acid process from domestic unconventional feedstocks such as Miscanthus, oat hulls, and intermediate flax straw were used herein to produce cellulose nitrates (CNs) with a high solubility. For the synthesis of CNs, a commercial technique was employed that involves nitration of cellulose with mixed acid containing 14 wt.% water followed by high-temperature treatment of the nitration product in acidic, alkaline, and neutral environments. The obtained CNs are similar in physicochemical attributes: 12.04–12.26% mass fraction of nitrogen, 10–14 mPa·s viscosity, and 98% solubility in alcohol– ester mixture. FTIR spectra of CNs had absorption bands (2559–2557, 1646–1631, 1277–1271, 825–812, 747–744, 683–680 cm-1) typical of nitro group vibrations. 13C NMR spectra showed chemical shifts representative of 6-mononitrocellulose, 2,6-dinitrocellulose, 3,6-dinitrocellulose, and 2,3,6-trinitrocellulose. DSC revealed that the resultant CNs were highly chemically pure with an exothermic peak at 209–212°С. The CNs obtained from the said unconventional feedstocks were compared with a commercial, highviscosity, lacquer-grade Colloxylin derived from cotton cellulose, as well as with other commercial Colloxylins, to show that the experimental CNs meet the requirements for comercial grades. Thus, the CNs obtained from the unconventional feedstocks are promising candidates as the component of composite explosives.

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Miscanthus × Giganteus var. KAMIS as a New Feedstock for Cellulose Nitrates

Journal of Siberian Federal University Chemistry ◽

10.17516/1998-2836-0206 ◽

2020 ◽

pp. 565-577

Author(s):

Anna A. Korchagina ◽

Yulia А. Gismatulina ◽

Vera V. Budaeva ◽

Vladimir N. Zolotukhin ◽

Nikolay V. Bychin ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Practical Importance ◽

Cellulose Nitrate ◽

Degree Of Polymerization ◽

Cellulose Content ◽

Cellulose Esters ◽

Synthesis Conditions ◽

Cellulose Nitrates ◽

Scanning Electron

Due to the limited volumes of conventional sources of cellulose (cotton and wood), research centered on producing the most competitive science-driven products – cellulose nitrates – from new, domestic, easily renewable feedstocks is extremely relevant. The review of scientific literature corroborates the lack of data on the feasibility to obtain cellulose nitrates from Miscanthus, except for the authors’ publications. Here we suggest a tree-like industrial crop, Miscanthus var. KAMIS, growing with an yield of up to 20 t/ha a year on industrial plantations in Kaliningradskaya, Kaluzhskaya and Yaroslavskaya Oblasts and in Primorskiy Krai. A pulp sample derived from Miscanthus var. KAMIS by the nitric-acid process exhibits a high α-cellulose content of 96 % and degree of polymerization of 1350. Under optimum synthesis conditions previously identified for unconventional feedstocks, a cellulose nitrate sample was synthesized by treating the pulp with commercially available mixed acid and had the following functional characteristics: 11.26 % nitrogen content, 52 mPа∙s viscosity, and – 95 % solubility on alcohol-ester mixture. Morphological features of pulp and cellulose nitrate samples were characterized by scanning electron microscopy. IR spectroscopy revealed the presence of functional groups in pulp samples (3411, 2913, 1637, 1429, 1369, 1317, 1161, 700-500 cm-1) and cellulose nitrate samples (2553, 1642, 1276, 830, 746, 680 cm-1), which allow those samples to be identified as cellulose and nitrate cellulose esters, respectively. It was found by scanning electron microscopy that the cellulose nitrate sample matches industrial Colloxylines by the onset temperature of decomposition (199 °С) and specific head of decomposition (8,43 kJ/g). The practical importance of this study is that we experimentally justify the feasibility to utilize the new, unconventional, domestic, easily renewable feedstock, Miscanthus var. KAMIS, as a precursor of high-quality cellulose nitrates

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THE RELATION BETWEEN THE SULPHATE AND NITROGEN CONTENT OF UNSTABILIZED CELLULOSE NITRATE

Canadian Journal of Chemistry ◽

10.1139/v58-028 ◽

1958 ◽

Vol 36 (1) ◽

pp. 212-214

Author(s):

Paul E. Gagnon ◽

Karl F. Keirstead ◽

Brian T. Newbold

Keyword(s):

Nitrogen Content ◽

Sulphuric Acid ◽

Cellulose Nitrate ◽

Cotton Cellulose ◽

Wood Cellulose ◽

Sulphate Content ◽

Mixed Acid ◽

Nitrogen Contents ◽

Mixed Acids ◽

Cellulose Nitrates

The sulphate and nitrogen contents of cellulose nitrates prepared from mixed acids containing different amounts of sulphuric acid were compared. The sulphate content showed a tendency to decrease with increasing nitrogen, for instance it was 1.96% for 10.54% and 0.44% for 13.31%. Similar results were obtained with a series of wood cellulose nitrates, for instance 2.40% for 11.01% and 0.91% for 12.47%. With practically the same amount of sulphuric acid in the mixed acid, cellulose nitrates were prepared and the sulphate and nitrogen contents were compared. For unstabilized cotton cellulose nitrates, the sulphate content decreased steadily with increasing nitrogen content. Similar results were obtained with wood cellulose nitrates.

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Metabolic Profiling of Xylooligosaccharides by Lactobacilli

Polymers ◽

10.3390/polym12102387 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2387

Author(s):

Ilia Iliev ◽

Tonka Vasileva ◽

Veselin Bivolarski ◽

Albena Momchilova ◽

Iskra Ivanova

Keyword(s):

Plasma Membranes ◽

Meat Products ◽

Lactobacillus Brevis ◽

Degree Of Polymerization ◽

Acid Fermentation ◽

Carbohydrate Utilization ◽

Beneficial Effects ◽

Mixed Acid ◽

Rat Liver Plasma Membranes ◽

Different Types

Three lactic acid bacteria (LAB) strains identified as Lactobacillus plantarum, Lactobacillus brevis, and Lactobacillus sakei isolated from meat products were tested for their ability to utilize and grow on xylooligosaccharides (XOSs). The extent of carbohydrate utilization by the studied strains was analyzed by HPLC. All three strains showed preferences for the degree of polymerization (DP). The added oligosaccharides induced the LAB to form end-products of typical mixed-acid fermentation. The utilization of XOSs by the microorganisms requires the action of three important enzymes: β-xylosidase (EC 3.2.1.37) exo-oligoxylanase (EC 3.2.1.156) and α-L-arabinofuranosidase (EC 3.2.1.55). The presence of intracellular β-D-xylosidase in Lb. brevis, Lb. plantarum, and Lb. sakei suggest that XOSs might be the first imported into the cell by oligosaccharide transporters, followed by their degradation to xylose. The studies on the influence of XOS intake on the lipids of rat liver plasma membranes showed that oligosaccharides display various beneficial effects for the host organism, which are probably specific for each type of prebiotic used. The utilization of different types of oligosaccharides may help to explain the ability of Lactobacillus strains to compete with other bacteria in the ecosystem of the human gastrointestinal tract.

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Novel Biobased Textile Fiber from Colombian Agro-Industrial Waste Fiber

Molecules ◽

10.3390/molecules23102640 ◽

2018 ◽

Vol 23 (10) ◽

pp. 2640 ◽

Cited By ~ 1

Author(s):

Maria Amaya Vergara ◽

Melissa Cortés Gómez ◽

Maria Restrepo Restrepo ◽

Jorge Manrique Henao ◽

Miguel Pereira Soto ◽

...

Keyword(s):

Textile Industry ◽

Industrial Waste ◽

Degree Of Polymerization ◽

Cellulose Content ◽

Short Fibers ◽

Cellulose Pulp ◽

Potential Applications ◽

Fique Fibers ◽

Regenerated Fibers ◽

Long Fibers

Fique fibers, native to Colombia, are traditionally used for ropes and bags. In the extraction of long fibers for these purposes, the same amount of short fibers is generated; the short fibers are then discarded in the soil or in landfills. This agro-industrial waste is cellulose-rich and can be potentially developed into new biobased products. As an alternative use for these fibers, viscose regenerated fibers with potential applications in the textile industry were developed. Fique waste fibers were pulped (to produce fique cellulose pulp, FCP) using a 33 design of experiment (DOE) to adjust the variables of the whitening treatment, and DOE analysis showed that time and hydrogen peroxide concentration do not have a significant effect on non-cellulosic remotion, unlike temperature. The behavior of this pulp in the production of viscose was compared against that of commercially available wood cellulose pulp (WCP). FCP showed a suitable cellulose content with a high degree of polymerization, which makes it a viable pulp for producing discontinuous viscose rayon filaments. Both pulps showed the same performance in the production of the viscose dope and the same chemical, thermal, and mechanical behavior after being regenerated.

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DESIGN STRUCTUR VARIABLES IN THE POSTERS OF THE INTERNATIONAL FILM AND TELEVISION FESTIVAL

RIMAK International Journal of Humanities and Social Sciences ◽

10.47832/2717-8293.3-3.34 ◽

2021 ◽

Vol 03 (03) ◽

pp. 379-387

Author(s):

Ayah Muosa MUHAMMAD ◽

Sahar Ali SARHAN

Keyword(s):

Cultural Awareness ◽

Practical Importance ◽

Research Problem ◽

Film Festival ◽

Design Elements ◽

Film And Television ◽

Design Structure ◽

Innovative Idea

Posters for cinematic festivals are an effective visual artistic way to address recipients (the audience), with their functional, aesthetic and expressive dimensions that contribute to spreading a variety of cultural awareness, especially those posters that specialize in their media and advertising performance, promotional and organizational, and cultural activities specified at certain time. Based on the foregoing, the researchers found that her research problem is summarized by the following question: What are the design structure variables in the designs of the film festival posters? The research consisted of four chapters as follows: The first chapter includes the research problem and the goal of the research, which is studying the variables of the design structure in the international film festival posters. As for its importance (theoretical importance / practical importance), the research limits (objective / spatial / temporal) and also include the most important terms. The second chapter includes the theoretical framework that the researcher divide into two topics, the first topic includes (the structure in the poster). As for the second topic (the variables in the poster structure) as well as previous studies and the most important indicators reached by the researcher, the third chapter includes research procedures that includes determining the method followed in analyzing samples for their scientific relevance in diagnosing the researched phenomenon, and the research community and the adult (6), and selecting a sample The research number (3) models after repeated exclusion from them, then the research tool, honesty and consistency. As for the fourth chapter, it includes the results of the research, conclusions, recommendations, and proposals, and the most important findings of the researcher were as follows: 1. The employment of the idea resulted in a fundamental variable in the structure of the poster, as the ideas differ according to the subject presented, in addition to the different idea from one designer to another. This is due to its frame of reference, which has a major impact in building the innovative idea that contributes to the presentation of the content. 2. Modern technologies have achieved the emergence of effective results in the design structure as an output variable that enhances the effectiveness of communication channels, and that this action has influential characteristics that have the ability to attract attention and direct impact on the recipient through the various technical treatments that the designer performs in constructing the poster and activating the role of technology in the structural display of the poster design elements. Either conclusion includes: 1. Structure variables are mainly related to the content of the design idea with the suitability of use, which is based on variable technical stylistic data.

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Preparation of chitosan oligomers and characterization: their antifungal activities and decay resistance

Holzforschung ◽

10.1515/hf.2011.130 ◽

2012 ◽

Vol 66 (1) ◽

Cited By ~ 15

Author(s):

Ibrar Hussain ◽

Tripti Singh ◽

Colleen Chittenden

Keyword(s):

Antifungal Activity ◽

Mycelial Growth ◽

Wood Decay ◽

Decay Resistance ◽

Degree Of Polymerization ◽

Raw Material ◽

Antifungal Activities ◽

Industrial Grade ◽

Principal Factors

Abstract Chitosan, a polymer of D-glucosamine, is known for its antimicrobial activity. However, the physicochemical properties of chitosan depend upon three principal factors, i.e., source of raw material, molecular weight and degree of deacetylation. Here, synthesis and characterization of chitosan oligomers is reported, which were prepared by the nitrous acid deaminative depolymerization of chitosan obtained from Sigma Aldrich and China (industrial grade). Subsequently, their antifungal activities were evaluated against selected basid-iomycetes. The nutrient medium bioassay results show that chitosans and chitosan oligomers affected mycelial growth to different magnitudes. Nevertheless, two of the low-MW chitosan oligomers completely inhibited the growth of all the tested fungi as compared to high-MW chitosan oligomers. Accordingly, antifungal activity increases by decreasing degree of polymerization of chitosan oligomers, which is divergent to literature data. The wood decay trial confirmed the antifungal activity of chitosan oligomers against basid-iomycetes. Chitosan is leachable by water.

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Insight into the Evolution of the Cellulose Microstructure Through the Enzyme Pretreatment Method

10.21203/rs.3.rs-391422/v1 ◽

2021 ◽

Author(s):

Qijun Ding ◽

Limin Jing ◽

Wenjia Han ◽

Yanpeng Guan ◽

Yifei Jiang ◽

...

Keyword(s):

Degree Of Polymerization ◽

Correlation Spectroscopy ◽

X Ray Diffraction ◽

Pretreatment Method ◽

X Ray ◽

Cellulosic Fibers ◽

Enzyme Pretreatment ◽

Theoretical Support ◽

Derivative Analysis ◽

Insight Into

Abstract In this work, the changes of properties and microstructure of cellulose (bleached hardwood kraft pulp (BHKP)) subjected to different enzyme pretreatment times (0–10 h) were explored for further fibrillation. The various properties of the pretreated cellulose gradually decrease with the elapse of time relative to the pristine material, such as yield, water retention value, aspect ratio and degree of polymerization, etc. Enzyme pretreatment can promote the peeling of fibrils and loosen the amorphous areas of cellulose identified by Scanning Electron Microscope (SEM) and X-ray diffraction (XRD). A thorough investigation of the relation between pretreatment and evolution of inter-/intra-molecular H-bonds in cellulose was conducted including content and cleave sequence of H-bonds by Fourier transform infrared spectroscopy (FTIR), second derivative analysis and generalized two-dimensional correlation spectroscopy (2DCOS). The intermolecular H-bonds with the most significant decrease in content was cleaved first relative to the intramolecular H-bonds. These discoveries provide theoretical support to more effective pretreatment method for commercial production of fibrils from cellulosic fibers.

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Assessing wood pulp reactivity through its rheological behavior under dissolution

Cellulose ◽

10.1007/s10570-019-02750-0 ◽

2019 ◽

Vol 26 (18) ◽

pp. 9877-9888

Author(s):

Sara Ceccherini ◽

Thad Maloney

Keyword(s):

Molecular Weight ◽

Water Retention ◽

Wood Pulp ◽

Degree Of Polymerization ◽

Cellulose Dissolution ◽

Water Retention Value ◽

Cellulosic Fibers ◽

Measurement Protocol ◽

Convenient Approach ◽

Viscose Process

Abstract Recent years have witnessed an increasing interest in man-made cellulosic fibers, whose production generally requires cellulose dissolution and regeneration. Cellulosic fibers are difficult to dissolve. Thus, the recalcitrance of wood pulp can be an estimate of its reactivity. Pulp reactivity is usually assessed via complex and time-consuming laboratory simulations of the viscose process. This study proposes a faster and more convenient approach. The dissolution-based torque reactivity (DTR) test measures the evolution of the rheological properties of a pulp suspension under dissolution in cupriethylenediamine. Reactivity is quantified in terms of initial dissolution rates (IDR) and dissolution times (DT). This study describes the measurement protocol for the DTR test and its application to some commercial pulps and a series of pulps hornified to different extents. The IDR and DT values were compared with other pulp features, including degree of polymerization, molecular weight distribution, specific surface area and water retention value. The DTR test proved to be reasonably precise and fast to carry out. Graphic abstract

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