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1.
Synthesis and characterization of fully biobased poly(propylene succinate‐ran‐propylene adipate). Analysis of the architecture‐dependent physicochemical behavior
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Thibaud Debuissy Eric Pollet Luc Avérous 《Journal of polymer science. Part A, Polymer chemistry》2017,55(17):2738-2748
Fully biobased aliphatic random poly(1,3‐propylene succinate‐ran‐1,3‐propylene adipate) (PPSA) copolyesters with high molar mass were synthesized with different macromolecular architectures based on various succinic acid/adipic acid (SA/AA) molar ratio, by transesterification in melt. Titanium (IV) isopropoxide was used as an effective catalyst. All synthesized copolyesters were fully characterized by different chemical and physicochemical techniques including NMR, size exclusion chromatography, FTIR, wide angle X‐ray scattering, differential scanning calorimetry, and thermogravimetric analysis. The final copolyesters molar compositions were identical to the feed ones. The different sequences based on succinate and adipate segments were randomly distributed along the chains. All the corresponding copolyesters showed an excellent thermal stability with a degradation onset temperature higher than 290 °C, which increased with the adipate content. According to their compositions and architectures, PPSA copolyesters can exhibit or not a crystalline phase, at room temperature. Tg of copolyesters decreased with the adipate content due to the decrease in the chains mobility, following the Gordon–Taylor relation. PPSA showed a pseudo eutectic melting behavior characteristic of an isodimorphic character. Finally, PPSA copolyesters were not able to crystallize during the cooling or the second heating run, due to the 1,3‐propanediol chemical structure, which led to amorphous materials with the exception of the polyester based solely on AA. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2738–2748 相似文献
2.
Lesly Dasilva Wandji Djouonkep Arnaud Kamdem Tamo Ingo Doench Naomie Beolle Songwe Selabi Emmanuel Monga Ilunga Arnaud Regis Kamgue Lenwoue Mario Gauthier Zhengzai Cheng Anayancy Osorio-Madrazo 《Molecules (Basel, Switzerland)》2022,27(1)
In this work, the feasibility of replacing petroleum-based poly(ethylene terephthalate) (PET) with fully bio-based copolyesters derived from dimethyl 2,5-thiophenedicarboxylate (DMTD), dimethyl 2,5-dimethoxyterephthalate (DMDMT), and polysaccharide-derived 1,6-hexanediol (HDO) was investigated. A systematic study of structure-property relationship revealed that the properties of these poly(thiophene–aromatic) copolyesters (PHS(20–90)) can be tailored by varying the ratio of diester monomers in the reaction, whereby an increase in DMTD content noticeably shortened the reaction time in the transesterification step due to its higher reactivity as compared with DMDMT. The copolyesters had weight-average molar masses (Mw) between 27,500 and 38,800 g/mol, and dispersity Đ of 2.0–2.5. The different polarity and stability of heterocyclic DMTD provided an efficient mean to tailor the crystallization ability of the copolyesters, which in turn affected the thermal and mechanical performance. The glass transition temperature (Tg) could be tuned from 70–100 °C, while the tensile strength was in a range of 23–80 MPa. The obtained results confirmed that the co-monomers were successfully inserted into the copolyester chains. As compared with commercial poly(ethylene terephthalate), the copolyesters displayed not only enhanced susceptibility to hydrolysis, but also appreciable biodegradability by lipases, with weight losses of up to 16% by weight after 28 weeks of incubation. 相似文献
3.
Maya-Stan Diakit Hlne Lenormand Vincent Lequart Santiago Arufe Patrick Martin Nathalie Leblanc 《Molecules (Basel, Switzerland)》2021,26(21)
The use of agricultural by-products in the building engineering realm has led to an increase in insulation characteristics of biobased materials and a decrease in environmental impact. The understanding of cell wall structure is possible by the study of interactions of chemical compounds, themselves determined by common techniques like Van Soest (VS). In this study, a global method is investigated to characterise the cell wall of hemp shiv. The cell wall molecules were, at first, isolated by fractionation of biomass and then analysed by physical and chemical analysis (Thermal Gravimetric Analysis, Elementary Analysis, Dynamic Sorption Vapor and Infra-Red). This global method is an experimental way to characterise plant cell wall molecules of fractions by Thermal Gravimetric Analysis following by a mathematical method to have a detailed estimation of the cell wall composition and the interactions between plant macromolecules. The analyzed hemp shiv presents proportions of 2.5 ± 0.6% of water, 4.4 ± 0.2% of pectins, 42.6 ± 1.0% (Hemicellulose–Cellulose), 18.4 ± 1.6% (Cellulose–Hemicellulose), 29.0 ± 0.8% (Lignin–Cellulose) and 2.0 ± 0.4% of linked lignin. 相似文献
4.
Chongxin Yin Min Wang Qingzhi Ma Huiyang Bian Hao Ren Hongqi Dai Jinlan Cheng 《Molecules (Basel, Switzerland)》2021,26(14)
Rice straw hydrotropic lignin was extracted from p-Toluene sulfonic acid (p-TsOH) fractionation with a different combined delignification factor (CDF). Hydrotropic lignin characterization was systematically investigated, and alkaline lignin was also studied for the contrast. Results showed that the hydrotropic rice straw lignin particle was in nanometer scopes. Compared with alkaline lignin, the hydrotropic lignin had greater molecular weight. NMR analysis showed that β-aryl ether linkage was well preserved at low severities, and the unsaturation in the side chain of hydrotropic lignin was high. H units and G units were preferentially degraded and subsequently condensed at high severity. High severity also resulted in the cleavage of part β-aryl ether linkage. 31P-NMR showed the decrease in aliphatic hydroxyl groups and the increasing carboxyl group content at high severity. The maximum weight loss temperature of the hydrotropic lignin was in the range of 330–350 °C, higher than the alkaline lignin, and the glass conversion temperature (Tg) of the hydrotropic lignin was in the range of 107–125 °C, lower than that of the alkaline lignin. The hydrotropic lignin has high β-aryl ether linkage content, high activity, nanoscale particle size, and low Tg, which is beneficial for its further valorization. 相似文献
5.
Alexander Orebom Davide Di Francesco Patrick Shakari Joseph S. M. Samec Clara Pierrou 《Molecules (Basel, Switzerland)》2021,26(11)
Lignin is an abundant polymeric renewable material and thus a promising candidate for incorporation in various commercial thermoplastic polymers. One challenge is to increase the dispersibility of amphiphilic lignin in lipophilic thermoplastic polymers We altered Kraft lignin using widely available and renewable fatty acids, such as oleic acid, yielding more than 8 kg of lignin ester as a light brown powder. SEC showed a molecular weight of 5.8 kDa with a PDI = 3.80, while the Tg of the lignin ester was concluded to 70 °C. Furthermore, the lignin ester was incorporated (20%) into PLA, HDPE, and PP to establish the thermal and mechanical behavior of the blends. DSC and rheological measurements suggest that the lignin ester blends consist of a phase-separated system. The results demonstrate how esterification of lignin allows dispersion in all the evaluated thermoplastic polymers maintaining, to a large extent, the tensile properties of the original material. The impact strength of HDPE and PLA blends show substantial loss upon the addition of the lignin ester. Reconverting the acetic acid side stream into acetic anhydride and reusing the catalyst, the presented methodology can be scaled up to produce a lignin-based substitute to fossil materials. 相似文献
6.
Wen‐Da Li Jian‐Bing Zeng Yi‐Dong Li Xiu‐Li Wang Yu‐Zhong Wang 《Journal of polymer science. Part A, Polymer chemistry》2009,47(21):5898-5907
A series of aliphatic–aromatic multiblock copolyesters consisting of poly(ethylene‐co‐1,6‐hexene terephthalate) (PEHT) and poly(L ‐lactic acid) (PLLA) were synthesized successfully by chain‐extension reaction of dihydroxyl terminated PEHT‐OH prepolymer and dihydroxyl terminated PLLA‐OH prepolymer using toluene‐2,4‐diisoyanate as a chain extender. PEHT‐OH prepolymers were prepared by two step reactions using dimethyl terephthalate, ethylene glycol, and 1,6‐hexanediol as raw materials. PLLA‐OH prepolymers were prepared by direct polycondensation of L ‐lactic acid in the presence of 1,4‐butanediol. The chemical structures, the molecular weights and the thermal properties of PEHT‐OH, PLLA‐OH prepolymers, and PEHT‐PLLA copolymers were characterized by FTIR, 1H NMR, GPC, TG, and DSC. This synthetic method has been proved to be very efficient for the synthesis of high‐molecular‐weight copolyesters (say, higher than Mw = 3 × 105 g/mol). Only one glass transition temperature was found in the DSC curves of PEHT‐PLLA copolymers, indicating that the PLLA and PEHT segments had good miscibility. TG curves showed that all the copolyesters had good thermal stabilities. The resulting novel aromatic–aliphatic copolyesters are expected to find a potential application in the area of biodegradable polymer materials. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5898–5907, 2009 相似文献
7.
Erik Gubbels Cristina Lavilla Antxon Martínez de Ilarduya Bart A. J. Noordover Cor E. Koning Sebastián Muñoz‐Guerra 《Journal of polymer science. Part A, Polymer chemistry》2014,52(2):164-177
The backbone of poly(butylene terephthalate) (PBT) was modified with 2,4:3,5‐di‐O‐methylene‐D ‐glucitol (Glux) using solid‐state modification (SSM). The obtained copolyesters proved to have a non‐random overall chemical microstructure. The thermal properties of these semicrystalline, block‐like, Glux‐based materials were extraordinary, showing higher melting points, and glass transition temperatures compared with other sugar‐based copolyesters prepared by SSM. These remarkable thermal properties were a direct result of the inherently rigid structure of Glux and the relatively slow randomization of the block‐like chemical microstructure of the Glux‐based copolyesters in the melt. SSM proved to be a versatile tool for preparing partially biobased copolyesters with superior thermal properties. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 164–177 相似文献
8.
α-Arylated carboxylic acids, esters and amides are widespread motifs in bioactive molecules and important building blocks in chemical synthesis. Thus, straightforward and rapid access to such structures is highly desirable. Here we report an organophotocatalytic multicomponent synthesis of α-arylated carboxylic acids, esters and amides from exhaustive defluorination of α-trifluoromethyl alkenes in the presence of alkyltrifluoroborates, water and nitrogen/oxygen nucleophiles. This operationally simple strategy features a unified access to functionally diverse α-arylated carboxylic acids, esters, and primary, secondary, and tertiary amides through backbone assembly from simple starting materials enabled by consecutive C–F bond functionalization at room temperature. Preliminary mechanistic investigations reveal that the reaction operates through a radical-triggered three-step cascade process, which involves distinct mechanisms for each defluorinative functionalization of the C–F bond.Here we report an organophotocatalytic synthesis of α-arylated carboxylic acids, esters and amides from exhaustive defluorination of α-trifluoromethyl alkenes in the presence of alkyltrifluoroborates, water and nitrogen/oxygen nucleophiles. 相似文献
9.
The search for alternative methods for the production of new materials or fuel from renewable and sustainable biomass feedstocks has gained increasing attention. In this study, Nypa fruticans (nipa palm) fronds from agricultural residues were evaluated to produce pure cellulose by combining prehydrolysis for 1–3 h at 150 °C, sulfur-free soda cooking for 1–1.5 h at 160 °C with 13–25% active alkali (AA), 0.1% soluble anthraquinone (SAQ) catalyst, and three-stage totally chlorine-free (TCF) bleaching, namely oxygen, peroxymonosulfuric acid, and alkaline hydrogen peroxide stages. The optimal conditions were 3 h prehydrolysis and 1.5 h cooking with 20% AA. Soda cooking with SAQ was better than the kraft and soda process without SAQ. The method decreased the kappa number as a residual lignin content index of pulp from 13.4 to 9.9–10.2 and improved the yields by approximately 6%. The TCF bleaching application produced pure cellulose with a brightness of 92.2% ISO, 94.8% α-cellulose, viscosity of 7.9 cP, and 0.2% ash content. These findings show that nipa palm fronds can be used to produce pure cellulose, serving as a dissolving pulp grade for viscose rayon and cellulose derivatives. 相似文献
10.
Natalia Sánchez-Arrieta Abdelilah Alla Sebastián Muñoz-Guerra 《European Polymer Journal》2005,41(7):1493-1501
Poly(ethylene terephthalate-co-1,4-cyclohexane dicarboxylate) copolymers, abbreviated as PETCHD, containing from 2 up to 40 mole% of the cycloaliphatic diacid, as well as the two parent homopolymers, PET and PECHD, were prepared from comonomer mixtures by a two-step melt-polycondensation procedure. Polymer intrinsic viscosities varied from 0.6 to 0.8 dL g−1 with weight-average molecular weights spanning in the range from 30,000 to 70,000. The copolymers were found to have a random microstructure and a composition according to that used in their corresponding feeds. Thermal and mechanical properties of PETCHD were evaluated as a function of composition. Copolymers were found to be crystalline for all examined compositions although they crystallize from the melt only when the cycloaliphatic comonomer composition was below 20 mole%. Both melting and glass transition temperatures of the copolyesters decreased rapidly with the content in CHD units, whereas the thermal stability appeared to be barely affected by copolymerization. Incorporation of 1,4-cyclohexane dicarboxylate units increased the Young’s modulus and the maximum tensile strength of these materials but elongation to break drastically diminished. Preliminary X-ray diffraction studies revealed that PETCHD copolyesters seem to adopt the same crystal structure as PET. 相似文献
11.
Nayef S Al-Muaikel 《European Polymer Journal》2003,39(5):1025-1033
A new interesting class of linear unsaturated polyesters based on dibenzylidenecycloalkanones have been synthesized by interfacial polycondensation of 4,4′-azodibenzoyl chloride or 3,3′-azodibenzoyl chloride with: 2,5-bis(p-hydroxybenzylidene)cyclopentanone I, 2,6-bis(p-hydroxybenzylidene)cyclohexanone II, 2,6-divanillylidenecyclohexanone III, or 2,7-bis(p-hydroxybenzylidene)cycloheptanone IV at ambient temperature. The copolyesters are also synthesized from the monomers I, II, III or IV with the diacid chlorides. The resulting polyesters and their copolyesters were characterized by elemental analyses, IR spectroscopy and solubility. Additionally, inherent viscosity of the polyesters in the range 0.32-0.86 dL g−1 and the inherent viscosity of the copolyesters in the range 0.28-0.65 dL g−1 were determined. The UV-visible spectra of certain polymers were measured in m-cresol solution and showed a characteristic absorption band at 435-473 nm due to n-π* transition. The thermal properties of the polymers were evaluated by thermo gravimetric analysis and differential scanning calorimetry measurements and correlated with their structural units. The crystallinity of some polyesters and copolyesters were tested. In addition, the electrical properties of all polyesters and copolyesters were measured. 相似文献
12.
The formation of amide bonds represents one of the most fundamental processes in organic synthesis. Transition-metal-catalyzed activation of acyclic twisted amides has emerged as an increasingly powerful platform in synthesis. Herein, we report the transamidation of N-activated twisted amides by selective N–C(O) cleavage mediated by air- and moisture-stable half-sandwich Ni(II)–NHC (NHC = N-heterocyclic carbenes) complexes. We demonstrate that the readily available cyclopentadienyl complex, [CpNi(IPr)Cl] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene), promotes highly selective transamidation of the N–C(O) bond in twisted N-Boc amides with non-nucleophilic anilines. The reaction provides access to secondary anilides via the non-conventional amide bond-forming pathway. Furthermore, the amidation of activated phenolic and unactivated methyl esters mediated by [CpNi(IPr)Cl] is reported. This study sets the stage for the broad utilization of well-defined, air- and moisture-stable Ni(II)–NHC complexes in catalytic amide bond-forming protocols by unconventional C(acyl)–N and C(acyl)–O bond cleavage reactions. 相似文献
13.
In this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis of formed macromolecules of synthesized bio-based copolyesters was conducted with the use of FTIR and 1H NMR spectroscopy and MALDI-ToF mass spectrometry. The results allowed to propose the majority of probable chemical structures of macromolecules formed during synthesis. Moreover, the impact of the structure on the thermal stability of the obtained copolyesters was also determined with the use of thermogravimetric analysis. The temperature of the beginning of thermal decomposition equaled even 330 °C. Furthermore, the results of DSC-TG/QMS coupled method confirmed that all prepared polyesters degraded by α and β-hydrogen bond scission mechanisms. 相似文献
14.
Morphology and performance of unsaturated polyester nanocomposites modified with organoclay and thermoplastic polyurethane 总被引:1,自引:0,他引:1
<正>Unsaturated polyester(UPR)/thermoplastic polyurethane(TPU)/organoclay nanocomposites were prepared by melt compounding of thermoplastic polyurethane and unsaturated polyester prepolymer,and then mixing with the hybrids of styrene monomers and organoclay at ambient temperature.The crosslinking reaction eventually occurred through the unsaturated polyester prepolymer and styrene monomer.The morphology of the composites was investigated by scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The results show that the impact strength of UPR/TPU/organoclay nanocomposites increases obviously;the cure shrinkage decreases markedly,the glass transition temperature is enhanced and an elastic response to the deformation is prominent at the temperature above 10℃. 相似文献
15.
Hans R. Kricheldorf Andreas Gerken Bakhodir Yulchibaev Christian Friedrich 《Journal of polymer science. Part A, Polymer chemistry》2000,38(11):2013-2022
Four series of liquid‐crystalline copolyesters were prepared by the transesterification of poly(ethylene terephthalate) (PET) with 4‐acetoxybenzoic acid (4‐ABA) or mixtures of 4‐ABA and acetylsalicylic acid (ASA). Two series consisted of 30 mol % PET, and the other two series consisted of 40 mol % PET. The molar ratio of 4‐HBA and ASA was varied in all four series from 0 to 25 mol %. One 30% PET series and one 40% PET series were prepared with the addition of acetic acid, which caused a more perfect randomization of the sequence but yielded slightly lower molecular weights. The incorporation of ASA reduced the crystallinity, which vanished completely at a salicylic acid (SA) content greater than 10 mol %. SA also reduced the stability of the nematic phase, but all the copolyesters were thermotropic up to a 20 mol % SA content. Furthermore, the molecular weights decreased with the increasing incorporation of ASA. Despite this negative trend, the melt viscosity and the storage and loss moduli passed a maximum between 5 and 10% SA. Obviously, the incorporation of SA favored the formation of entanglements. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2013–2022, 2000 相似文献
16.
Zhoulong Fan Shuai Zhao Tao Liu Peng-Xiang Shen Zi-Ning Cui Zhe Zhuang Qian Shao Jason S. Chen Anokha S. Ratnayake Mark E. Flanagan Dominik K. Klmel David W. Piotrowski Paul Richardson Jin-Quan Yu 《Chemical science》2020,11(45):12282
DNA-encoded library (DEL) technology has the potential to dramatically expedite hit identification in drug discovery owing to its ability to perform protein affinity selection with millions or billions of molecules in a few experiments. To expand the molecular diversity of DEL, it is critical to develop different types of DNA-encoded transformations that produce billions of molecules with distinct molecular scaffolds. Sequential functionalization of multiple C–H bonds provides a unique avenue for creating diversity and complexity from simple starting materials. However, the use of water as solvent, the presence of DNA, and the extremely low concentration of DNA-encoded coupling partners (0.001 M) have hampered the development of DNA-encoded C(sp3)–H activation reactions. Herein, we report the realization of palladium-catalyzed C(sp3)–H arylation of aliphatic carboxylic acids, amides and ketones with DNA-encoded aryl iodides in water. Notably, the present method enables the use of alternative sets of monofunctional building blocks, providing a linchpin to facilitate further setup for DELs. Furthermore, the C–H arylation chemistry enabled the on-DNA synthesis of structurally-diverse scaffolds containing enriched C(sp3) character, chiral centers, cyclopropane, cyclobutane, and heterocycles.DNA-compatible C(sp3)–H activation reactions of aliphatic carboxylic acids, amides, and ketones were developed for efficient access to DEL synthesis. 相似文献
17.
Green and renewable foaming poly(lactic acid) (PLA) represents one of the promising developments in PLA materials. This study is the first to use the lignin graft PLA copolymer (LG‐g‐PLA) to improve the foamability of PLA as a biobased nucleating agent. This agent was synthesized via ring‐opening polymerization of lignin and lactide. The effects of LG‐g‐PLA on cell nucleation induced by the crystallization, rheological behavior, and foamability of PLA were evaluated. Results indicated that LG‐g‐PLA can improve the crystallization rate and crystallinity of PLA, and play a significant nucleation role in the microcellular foam processing of PLA. LG‐g‐PLA improved the foam morphology of PLA, obtaining a reduced and uniform cell size as well as increased expansion ratio and cell density. With the addition of 3 wt% LG‐g‐PLA content, the PLA/LG‐g‐PLA foams increased the compressive strength 1.6 times than that of neat PLA foams. The improved foaming properties of PLA via a biobased nucleating agent show potential for the production and application of green biodegradable foams. 相似文献
18.
K. Van Aelst E. Van Sinay T. Vangeel E. Cooreman G. Van den Bossche T. Renders J. Van Aelst S. Van den Bosch B. F. Sels 《Chemical science》2020,11(42):11498
In-depth structural analysis of biorefined lignin is imperative to understand its physicochemical properties, essential for its efficient valorization to renewable materials and chemicals. Up to now, research on Reductive Catalytic Fractionation (RCF) of lignocellulose biomass, an emerging biorefinery technology, has strongly focused on the formation, separation and quantitative analysis of the abundant lignin-derived phenolic monomers. However, detailed structural information on the linkages in RCF lignin oligomers, constituting up to 50 wt% of RCF lignin, and their quantification, is currently lacking. This study discloses new detailed insights into the pine wood RCF lignin oil''s molecular structure through the combination of fractionation and systematic analysis, resulting in the first assignment of the major RCF-derived structural units in the 1H–13C HSQC NMR spectrum of the RCF oligomers. Specifically, β-5 γ-OH, β-5 ethyl, β-1 γ-OH, β-1 ethyl, β-β 2x γ-OH, β-β THF, and 5-5 inter-unit linkages were assigned unambiguously, resulting in the quantification of over 80% of the lignin inter-unit linkages and end-units. Detailed inspection of the native lignin inter-unit linkages and their conversion reveals the occurring hydrogenolysis chemistry and the unambiguous proof of absence of lignin fragment condensation during proper RCF processing. Overall, the study offers an advanced analytical toolbox for future RCF lignin conversion and lignin structural analysis research, and valuable insights for lignin oil valorization purposes.In-depth structural analysis of pine wood RCF lignin discloses new detailed insights into the RCF lignin oil''s molecular structure. 相似文献
19.
Matiss Pals Maris Lauberts Douwe S. Zijlstra Jevgenija Ponomarenko Alexandr Arshanitsa Peter J. Deuss 《Molecules (Basel, Switzerland)》2022,27(10)
European aspen (Populus tremula (L.) (Salicaceae)) bark is a promising raw material in multi-step biorefinery schemes due to its wide availability and higher content of secondary metabolites in comparison to stem wood biomass. The main objective of this study was to investigate the major cell wall component-enriched fractions that were obtained from aspen bark residue after extractives isolation, primarily focusing on integration of separated lignin fractions and cellulose-enriched bark residue into complex valorization pathways. The “lignin first” biorefinery approach was applied using mild organosolv delignification. The varying solvent systems and process conditions for optimal delignification of residual aspen bark biomass were studied using a response surface methodology approach. The conditions for maximum process desirability at which the highest amount of lignin-enriched fraction was separated were as follows: 20-h treatment time at 117 °C, butanol/water 4:1 (v/v) solvent system with solid to liquid ratio of 1 to 10. At optimal separation conditions, lignin-enriched fraction exhibited a higher content of β–O–4 linkages vs. C–C linkages content in its structure as well as a high amount of hydroxyl groups, being attractive for its further valorization. At the same time, the content of glucose in products of cellulose-enriched residue hydrolysis was 52.1%, increased from 10.3% in untreated aspen bark. This indicates that this fraction is a promising raw material for obtaining cellulose and fermentable glucose. These results show that mild organosolv delignification of extracted tree bark can be proposed as a novel biorefinery approach for isolation of renewable value-added products with various application potentials. 相似文献
20.
Tawakaltu AbdulRasheed-Adeleke Evans Chidi Egwim Emmanuel Rotimi Sadiku Stephen Shaibu Ochigbo 《Molecules (Basel, Switzerland)》2022,27(22)
The optimization of the production of thermoplastic starch (TPS) bionanocomposite films for their potential application in food packaging was carried out, according to the Box–Wilson Central Composite Design (CCD) with one center point, using Response Surface Methodology (RSM) and fillers based on lignin and nanofiber, which were derived from bamboo plant. The effects of the fillers on the moisture absorption (MAB), tensile strength (TS), percent elongation (PE) and Young’s modulus (YM) of the produced films were statistically examined. The obtained results showed that the nanocomposite films were best fitted by a quadratic regression model with a high coefficient of determination (R2) value. The film identified to be optimum has a desirability of 76.80%, which is close to the objective function, and contained 4.81 wt. % lignin and 5.00 wt. % nanofiber. The MAB, TS, YM and PE of the identified film were 17.80%, 21.51 MPa, 25.76 MPa and 48.81%, respectively. The addition of lignin and cellulose nanofiber to starch composite was found to have reduced the moisture-absorption tendency significantly and increased the mechanical properties of the films due to the good filler/matrix interfacial adhesion. Overall, the results suggested that the produced films would be suitable for application as packaging materials for food preservation. 相似文献