Phenolic Polymers Research Articles

Graphene nanoplatelets loaded polyurethane and phenolic resin fibres by combination of pressure and gyration

A simple and effective process combining pressure and gyration has been developed and used to jet-out composite fibres containing graphene nanoplatelets. Thermoplastic polyurethane and phenolic resin polymers were used as matrices. Processing parameters such as rotation speed, pressure and polymer concentration had a marked influence on the composite fibre diameter. Focussed ion beam milling and etching verified the effective incorporation of the graphene nanoplatelets into the composite fibres. Morphological, rheological, physico-chemical and thermal properties of the composite fibres were evaluated to identify possible applications for them.

Synthesis of porous silicon nitride using silica/carbon composite derived from phenol–resorcinol–formaldehyde gel

Mesoporous silicon nitride (Si3N4), which is one of the most promising structural materials for applications in high-temperature filtration, was synthesized from the carbothermal reduction and nitridation of a pyrolyzed silica-containing phenol-resorcinol-formaldehyde (PRF) gel. The PRF gel was synthesized by combining sol–gel and polymerization of phenol, resorcinol and formaldehyde using sodium carbonate as a catalyst. Silica was incorporated into the gel by addition of 3-aminopropyl trimethoxysilane (APTMS) as a silica precursor. After aging and being freeze-dried, the silica/PRF composite was pyrolyzed under nitrogen gas to convert it into porous silica/carbon composite. The combination of phenol-formaldehyde (PF) and resorcinol-formaldehyde (RF) gels into PRF gel, allows further enhancement in porosity of the silica/carbon composite via pre-calcination in the range of 400–500°C, since carbon derived from PF gel and that from RF gel have different thermal stability. The final product obtained after final calcination to remove residual carbon has a surface area as high as 194m2/g, which is significantly much higher than the conventional Si3N4 granules. Specific surface area of the product is affected by molar ratio of phenol-to-resorcinol, molar ratio of silica-to-carbon, and the pre-calcination temperature.

Relief of Cure Stress in Prepreg Composites with Engineered Voids: A Solution to Warping in Composite Phenolic Resin/Fiberglass Laminates

The warp of a phenolic resin/fiberglass honeycomb composite panel is investigated using void and volatile analysis, and a solution to geometric warp is proposed and tested. The surface void content in semicured phenolic polymer composite facesheets was found to be an indicator for the average warp value of a fully cured composite laminate panel. Several potential sources in the resin formulation for producing voids in the phenolic resin/fiberglass composite sheets were investigated. Ultimately, high surface tension and polymer incompatible cosolvents are correlated to the population of voids. It is proposed that these voids act as sites for the relief of internal stresses that develop in the phenolic matrix during the final cure of the part. Void-inducing additives are added at the formulation stage which phase separate from the polymer matrix in partially cured fiberglass/phenolic composite sheets, and upon evaporation, lead to voids that prevent warping in honeycomb composite panels.

Mesoporous In-Sn binary oxides of crystalline framework with extended compositional variation

Indium-tin oxide is considered a highly promising mixed-metal oxide system, because it shows good performance in various industrial processes. Therefore, it will be of great importance to explore the possibility of obtaining new In-Sn oxides with controlled contents whose properties could be tailored. However, In or Sn content in In-Sn oxides has generally been restricted to <10% because of their low solid solubility into counterpart metal oxide framework. Herein, we report for the first solvothermal synthesis of crystalline mesoporous In-Sn oxides with a broad range of In/Sn ratios and their opto-electrochemical properties. For the synthesis, we use phenolic polymer as a structure-directing agent. Surprisingly, we observe that the phenolic polymer plays a critical role in overcoming their low solubility by manipulating kinetics of crystal nucleation and subsequet growth. As a result, we obtain In-rich rutile SnO2 phase without phase separation with up to 50% In content and Sn-rich rhombohedral In2O3 structure with higher In content. The synthesized materials are highly transparent regardless of In content. The electrochemical properties are sensitive to In content. Our strategy offers possibility of realizing crystalline mesoporous mixed-metal oxides with tunable contents, thus opening a new perspective for the development of optoelectronic materials.

Improving the synthesis of phenolic polymer using Coprinus cinereus peroxidase mutant Phe230Ala

The F230A mutant of Coprinus cinereus peroxidase (CiP), which has a high stability against radical-inactivation, was previously reported. In the present study, the radical-robust F230A mutant was applied to the oxidative polymerization of phenol. The F230A mutant exhibited better polymerization activities than the wild-type CiP in the presence of water-miscible alcohols i.e., methanol, ethanol, and isopropanol despite its lower stability against alcohols. In particular, the F230A mutant showed a higher consumption of phenol (40%) and yielded phenolic polymer of larger molecular weight (8850Da) in a 50% (v/v) isopropanol-buffer mixture compared with the wild-type CiP (2% and 1519Da, respectively). In addition, the wild-type CiP and F230A mutant had no significant differences in enzyme inactivation by physical adsorption on the polymeric products or by heat incubation, and showed comparable kinetic parameters. These results indicate that high radical stability of the F230A mutant and improved solubility of phenolic polymers in alcohol-water cosolvent systems may synergistically contribute to the production of the high molecular weight phenolic polymer.

Colour-related phenolics, volatile composition, and sensory profile of Nero di Troia wines treated with oak chips or by micro-oxygenation

The changes of Nero di Troia wines submitted to micro-oxygenation or treatment with oak chips were studied. Oak chips favoured polymerization reactions (SPP, LPP, I HCl, polymeric phenols, and polymeric pigments, respectively +28, +67, +44, +60, and +73 % in comparison with the untreated wines, 12 months after racking). The polymerization reactions increased colour stability (colour intensity, and % of red and blue colour of the oak-treated wines were +11, +2, and +10 % compared to the control). At the end of ageing, the oak-treated wines had the highest concentrations of alcohols, carbonyl compounds, and lactones, while the highest contents of acids and esters were detected in the micro-oxygenated wines. The sensory profile of the oak-treated wines was characterized by the attenuation of floral, fruity, and vinous attributes. Concerning the phenolic profile, micro-oxygenated wines showed the highest concentrations of anthocyanins (+23 % respect to the untreated samples and +306 % respect to the oak-treated ones) and of flavan-3-ols (+24 % respect to the untreated samples and +95 % respect to the oak-treated ones). Micro-oxygenation reduced astringency and herbaceous character and intensified spicy and fruity flavours.

Supercapacitor performances of rich nitrogen-doped mesoporous graphene fabricated by a facile template-free copyrolysis process

Rich nitrogen-doped mesoporous graphene (NDMG) with a large specific surface area of 496.8 m2 g−1 and high electrical conductivity of 327.2 S cm−1, and suitable pore size was synthesized by a facile co-thermal annealing of pre-prepared phenolic polymer and dicyandiamide. The NDMG has a high nitrogen content (7.9 wt%) and can act as promising electroactive materials for two-electrode symmetric supercapacitors. The NDMG cells displayed a high specific capacitance of ca. 316 F g−1 at 0.5 A g−1, which is much higher than that of the pristine graphene devices (ca. 123 F g−1). Moreover, compared with the capacitance drop rate of pristine graphene devices (8.9 %), the specific capacitance of NDMG cells was decreased by only 3.2 % after 2000 cycles, exhibiting a good cycling performance and reversibility. In addition, the specific capacitance of the NDMG cells can reach 251 F g−1 at 5.0 A g−1, revealing an excellent rate capability and implying the ability to deliver a high energy density at a high power density. The good electrochemical performances of NDMG can be attributed to its high surface area, suitable mesopore size, and high electrical conductivity.

Carbon molecular sieve membranes on porous composite tubular supports for high performance gas separations

Carbon molecular sieve (CMS) membranes on the inside of porous composite stainless steel supports were developed for gas separation in this research effort. The intermediate alumina layer was introduced to reduce the pore size of the porous stainless steel tube and subsequently provide uniform surface roughness. Viscosity of the phenolic polymer solution was varied from 10 to 30 centipoises (cP) to maximize performance of the CMS membranes. Pyrolysis temperature was also varied from 700 °C to 900 °C to optimize the fabrication of uniform CMS membranes on porous composite stainless steel supports. High performance CMS membranes were obtained from triple coatings and subsequent pyrolysis at 700 °C. The viscosity of precursor solutions played a critical role to determine the performance of CMS membranes in terms of gas permeance and ideal gas separation factor. The highest separation performance of the CMS membranes was shown with viscosity of 20 cP, resulting in gas separation factor of 462 for He/N2, 97 for CO2/N2, and 15.4 for O2/N2.

Characterization of Cell Wall Components and Their Modifications during Postharvest Storage of Asparagus officinalis L.: Storage-Related Changes in Dietary Fiber Composition.

Changes in cell wall composition during storage of plant foods potentially alter the physiological effects of dietary fiber components. To investigate postharvest cell wall modifications of asparagus and their consequences in terms of insoluble dietary fiber structures, asparagus was stored at 20 and 1 °C for different periods of time. Structural analyses demonstrated postharvest changes in the polysaccharide profile, dominated by decreased portions of galactans. Increasing lignin contents correlated with compositional changes (monolignol ratios and linkage types) of the lignin polymer as demonstrated by chemical and two-dimensional nuclear magnetic resonance (2D-NMR) methods. Depending on the storage time and temperature, syringyl units were preferentially incorporated into the lignin polymer. Furthermore, a drastic increase in the level of ester-linked phenolic monomers (i.e., p-coumaric acid and ferulic acid) and polymer cross-links (di- and triferulic acids) was detected. The attachment of p-coumaric acid to lignin was demonstrated by 2D-NMR experiments. Potential consequences of postharvest modifications on physiological effects of asparagus dietary fiber are discussed.

One-step assembly of a hierarchically porous phenolic resin-type polymer with high stability for CO2 capture and conversion.

A hierarchically porous phenolic resin-type polymer has been successfully prepared by a solvothermal reaction. Given the relatively high surface area, hierarchical pores, good stability and abundant -OH reactive groups, this polymer exhibits high CO2 adsorption and efficient catalytic conversion for CO2 cycloaddition.

干旱区典型盐生植物群落下土壤微生物群落特征

PDF HTML阅读 XML下载 导出引用 引用提醒 干旱区典型盐生植物群落下土壤微生物群落特征 DOI: 10.5846/stxb201410061958 作者: 作者单位: 石河子大学 石河子 832003,石河子大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(31360320); 教育部科学技术研究项目(213039A); 兵团技术转移专项(2013BD051) Soil microbial properties under typical halophytic vegetation communities in arid regions Author: Affiliation: Shihezi University,Shihezi University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:运用Biolog技术,对干旱区玛纳斯河流域扇缘带的6种典型盐生植物群落下土壤微生物群落特征差异性进行了研究,探讨不同植物群落对土壤微生物群落的影响。结果表明:不同盐生植物群落土壤平均颜色变化率(AWCD)随培养时间的延长而逐渐增加, 大小顺序依次为:梭梭 > 花花柴 > 白刺 > 绢蒿 > 柽柳 > 雾冰藜,且差异显著。不同植物群落土壤微生物对6类碳源利用差异显著(P < 0.05),其中梭梭群落利用率最高,雾冰藜群落利用率最低。碳水化合物类和氨基酸类是主要碳源,胺类的利用率最低。主成分分析(PCA)表明,在31种因子中提取的2个主成分因子,分别可以解释所有变量方差的41.51%和25.35%,对PC1 和PC2起分异作用的主要碳源分别为碳水化合物类和氨基酸类。土壤微生物群落Shannon指数、Simpson指数上,除雾冰藜群落较低,其他群落之间均差异不显著(P > 0.05)。植物群落Margalef指数,Shannon指数和Simpson指数上,均为绢蒿,梭梭和柽柳群落较为优势。相关性分析表明,植物群落多样性指数与土壤微生物多样性指数呈显著正相关关系(P < 0.05),说明了植物多样性越丰富,土壤微生物越丰富。总体来说,干旱区不同盐生植物群落对土壤微生物群落多样性具有重要影响。其中,梭梭群落的土壤微生物群落具有较强的微生物总体活性和功能多样性。 Abstract:Soil microbes play a key role in material recycling and energy conversion in arid areas. Currently, research on soil microbial community diversity mainly focuses on environmental change and human disturbance, and not on natural ecosystems. In Xinjiang, a variety of halophytes develop in arid areas, and play an active role in the balance of desert oases ecosystems, but there are relatively few studies on soil microbial community diversity in different halophyte communities. The difference between soil microbial diversity and carbon source utilization under different halophyte communities needs to be elucidated. Therefore, a field experiment was conducted to quantify changes in the functional diversity of the soil microbial community under six halophyte communities (Nitraria tangutorum, Seriphidium kaschgaricum, Karelinia caspia, Bassia dasyphylla, Tamarix ramosissima, and Haloxylon ammodendron) using Biolog analysis in the alluvial fan area of the Manas River watershed. The objective of the present study was to determine 1) the effects of different halophyte communities on carbon source utilization, 2) which halophyte community has stronger activity and microbial functional diversity and 3) the relationship of the ground vegetation diversity and soil microbial community diversity. The results revealed that the average well color development (AWCD) increased with increasing incubation time, and there were significant differences among different vegetation communities, in order of H. ammodendron > K. caspia > N. tangutorum > S. kaschgaricum > T. ramosissima > B. dasyphylla (P < 0.05). There were significant differences among substrates used by soil microbial communities in different halophyte communities (P < 0.05). The substrate used in H. ammodendron was the highest, and that in B. dasyphylla was the lowest. The carbon sources most used by soil microbes were carbohydrates and amino acids, followed by phenolic acids, polymers and carboxylic acids, and the lowest was amines. Principal component analysis (PCA) identified two factors related to carbon sources explaining 4.51% and 25.35% of the variation. Carbohydrates and amino acids were the two main carbon sources separating the two principal component factors. The Shannon and Simpson indices of soil microbial communities in B. dasyphylla were significantly lower than in other communities (P < 0.05), the Pielou index of soil microbial community in N. tangutorum was significantly higher than in other communities (P < 0.05), and there were no significant differences between other communities (P > 0.05). The Margalef, Shannon, and Simpson indices of vegetation communities in S. kaschgaricum, H. ammodendron, and T. ramosissima were more dominant. There were significantly positive correlations between the indices of vegetation richness, diversity, dominance, and soil microbial diversity and dominance (P < 0.05), showing that richer vegetation diversity was related to richer soil microbial diversity. Overall, different halophytic communities have important effects on soil microbial communities in arid areas. The soil microbial community of H. ammodendron has the highest microbial activity and functional diversity. 参考文献 相似文献 引证文献

CHARACTERIZATION OF RIPENING STAGES OF MYRTLE FRUIT

ABSTRACT The myrtle (Eugenia gracillima Kiaersk.) is a native fruit species in the Chapada of Araripe, state of Pernambuco, Brazil. The fruits are collected from the wild and are consumed fresh or processed as pulp, juice, jelly, liquor or desserts. Myrtle fruit production is of significant socioeconomic value for the region and, therefore, the description of myrtle fruit ripening stages may contribute to the development of its production chain. As a result, the objective of the present study was to evaluate the physical, quality and ripening changes of myrtle fruits at different developmental stages. The fruits were picked at five distinctive stages and evaluated for longitudinal and transverse diameters; fresh, dry and water mass; water contents; soluble solids (SS); titratable acidity (TA); pH; SS/TA ratio; carbohydrates (starch, total, reducing and nonreducing sugars); ascorbic acid; total pectin, soluble pectins and percentage of pectin solubilization; polymeric, oligomeric and dimeric phenolics; total anthocyanins, carotenoids and chlorophyll; and yellow flavonoids. Along fruit ripening processes increases in SS, anthocyanins and carotenoids, in the SS/TA ratio and of percentages of pectin solubilization were determined. On the other hand, decreases in TA and total chlorophyll were observed. The ripening stage at which peel color is completely dark red (ripening stage 4) is most appropriate to harvest myrtle fruits for human consumption.

Counterintuitive phenomena in the interaction of long-wavelength acoustical plane waves with a viscoelastic cylinder in a non-viscous fluid

Surprising effects occurring during the interaction of acoustical plane wavefronts with a viscoelastic cylinder in the long-wavelength (Rayleigh) limit and at normal incidence are elucidated. Those phenomena include the emergence of a negative axial radiation force acting in opposite direction of wave propagation, the abnormal production of negative absorption and extinction efficiencies as well as the anomalous enhancement of the scattering efficiency as a consequence of acoustic attenuation inside the cylinder material. Numerical results are performed for a viscoelastic phenolic polymer cylinder immersed in a non-viscous host liquid (i.e. water) with particular emphasis on the shear-wave absorption coefficient of the cylinder. The computations for the radiation force function as well as the extinction, absorption and scattering efficiencies demonstrate that the monopole partial-wave plays a sole prominent role in the generation of the counterintuitive phenomena mentioned earlier. The monopole partial-wave (n=0) mode has a contribution caused by the attenuation of shear waves inside the core material of the viscoelastic cylinder.

Characterization of macromolecular complexes in red wine: Composition, molecular mass distribution and particle size

Precipitates were prepared from two compositionally different Pinot noir wines with addition of excess ethanol, and contained primarily polysaccharide, tannin and protein. The ethanol-soluble material was further fractionated into polymeric (tannin) and monomeric phenolics. Tannin associated with precipitates was of a higher molecular mass than that remaining in ethanolic solution. Wine fractions were reconstituted at the ratios of the original wine and analyzed using nanoparticle tracking analysis. The average particle size of the tannin fraction was 75–89nm, and increased when combined with the precipitate (≅200nm). Addition of the monomeric fraction to the tannin–precipitate complex increased both the incidence and concentration of smaller particles, reducing the average particle size. The formation of aggregates occurred in all fractions and only minor differences in particle size distribution were found between wines. Differences in particle concentration between wines appear to be due to differences in the total concentration of macromolecules rather than compositional differences.

Propargyl resin derived from biosynthesized oligophenols for the application of high temperature composite matrix

AbstractA novel addition‐cure‐type propargyloligophenol resin for high‐temperature usage was prepared via a two‐step process: Horseradish Peroxidase (HRP) catalyzed oxidation polymerization of phenols to oligophenols, and Williamson etherification of oligophenols to propargyloligophenols. Propargyloligophenols possess an ideal processability for composite manufacture, i.e. good solubility, low melting point (&lt; 50 °C), and thermal curability. As shown by Differential Scanning Calorimetry (DSC), propargyloligophenol resin upon heating experiences a broad thermal exothermic peak in the range of 175–300 °C peaking at around 260 °C. The cured resin is high‐temperature resistant with an initial decomposition temperature &gt; 400 °C and an anaerobic char yield &gt; 60 % at 700 °C. The mechanical properties of glass fabric‐reinforced propargyloligophenol laminate were superior to those of conventional phenolic resins. The results showed that propargyloligophenol resin is a prospective polymeric matrix for high temperature composites.

Effects of the treatment with oak chips on color-related phenolics, volatile composition, and sensory profile of red wines: the case of Aglianico and Montepulciano

The effects of the treatment of two important Italian wines, Aglianico and Montepulciano, with French oak chips were analyzed. The study was focused on the changes of color-related compounds such as anthocyanins and tannins, and of volatile and sensory profiles. An overall characterization of the wines was also performed. With reference to the phenolic profile, the behaviors of the two wines were different due to their different initial phenolic composition. The oak-chip treatments favored the polymerization of anthocyanins and tannins, whose concentrations in the oak-treated Aglianico samples were lower than in the controls (anthocyanins, −84 %; tannins, −71 %), while in the oak-treated Montepulciano wine the decrease concerned only anthocyanins (−57 %). The concentrations of polymeric phenols increased with aging in all the samples and, after 12 months, were higher in oak-treated wines than in the controls (+43 % in Aglianico, +39 % in Montepulciano). After 12 months of aging, the volatile profile of Aglianico oak-treated wines highlighted the highest acid (+68 %), terpene (+371 %), and lactone (+60 %) concentrations, while the oak-treated Montepulciano wine showed higher acid (+15 %), alcohol (+5 %), and lactone (+50 %) concentrations than the control wine. The sensory profile of the treated wines was characterized by high scores assigned to astringency and appearance of the typical oak aromas (woody, vanilla, and spicy notes) and the attenuation of floral and fruity attributes. These changes were responsible for the increase in intensity of the tannic character in Aglianico wine and the improvement of the Montepulciano wine aroma with respect to the corresponding untreated wines.

Enzymatic synthesis of polyguaiacol and its thermal antioxidant behavior in polypropylene

Polyguaiacol was successfully synthesized by enzyme-catalyzed polymerization in an aqueous micelle system with horseradish peroxidase (HRP) as the catalyst. As-synthesized polyguaiacol was characterized by infrared spectrometry and gel permeation chromatography, and its thermal stability was evaluated by thermogravimetric analysis. Besides, the thermal antioxidant behavior of the as-synthesized phenolic polymer as an antioxidant in polypropylene was evaluated by differential scanning calorimetry and accelerated aging test, and the apparent activation energies of thermal decomposition of polypropylene (PP) were calculated by Friedman method. Results show that the as-synthesized polyguaiacol as an antioxidant is able to significantly increase the oxidation induction time of virgin PP, and it exhibits better antioxidative performance than corresponding monomer. Moreover, polyguaiacol, the as-synthesized phenolic polymer, exhibits good resistance against aging of polypropylene.

An ab initio molecular dynamics analysis of lignin as a potential antioxidant for hydrocarbons

Lignins are complex phenolic polymers with limited industrial uses. To identify new applications of lignins, this study aims to evaluate the conifer alcohol lignin as a potential antioxidant for hydrocarbons, using the petroleum asphalt as an example. Using the ab initio molecular dynamics (AIMD) method, the evaluation is accomplished by tracking the generation of critical species in a lignin-asphalt mixture under a simulated oxidative condition. The generation of new species was detected using nuclear magnetic resonance and four analytical methods including density of states analysis, highest occupied molecular orbital and lowest unoccupied molecular orbital analyses, bonding and energy level analysis, and electrostatic potential energy analysis. Results of the analyses show that the chemical radicals of carbon, nitrogen and sulfur generated in the oxidation process could enhance the agglomeration and/or decomposition tendency of asphalt. The effectiveness of lignins as an antioxidant depends on their chemical compositions. Lignins with a HOMO–LUMO gap larger than the HOMO–LUMO gap of the hydrocarbon system to be protected, such as the conifer alcohol lignin to protect petroleum asphalt as was studied in this work, do not demonstrate beneficial anti-oxidation capacity. Lignins, however, may be effective oxidants for hydrocarbon systems with a larger HOMO–LUMO gap. In addition, lignins may contain more polar sites than the hydrocarbons to be protected; thus the lignins’ hydrophobicity and compatibility with the host hydrocarbons need to be well evaluated. The developed AIMD model provides a useful tool for developing antioxidants for generic hydrocarbons.

Failure of single phenolic chains and cross-links: Energetics, mechanisms, and alternative linker design

The stretching of a single chain of phenolic polymer is studied using density functional theory (DFT) and the reactive force field (ReaxFF) potential. The most detailed studies are performed at 0 K, which shows the breaking of the C(ring)-CH2 bridge bond can be delayed to longer polymer length by a ring opening mechanism that relieves the strain. Molecular dynamics (MD) simulations, using the DFT approach, show that C–CH2 bridge bond breaking occurs much more frequently than the ring opening. The stretching potentials determined using ReaxFF compare favorably with the DFT results. Using ReaxFF, stretching of cross-linked systems were considered and compared to single chains. The effect of changing the linking group on the bond stretching portion of the potential is found to be relatively small, but the effect on the bond energies can be significant.

Laccases for biorefinery applications: a critical review on challenges and perspectives.

Modern biorefinery concepts focus on lignocellulosic biomass as a feedstock for the production of next generation biofuels and platform chemicals. Lignocellulose is a recalcitrant composite consisting of several tightly packed components which are stuck together by the phenolic polymer lignin hampering the access to the carbohydrate compounds of biomass. Certain saprophytic organisms are able to degrade lignin by the use of an enzymatic cocktail. Laccases have been found to play a major role during lignin degradation and have therefore been intensively researched with regard to potential applications for biomass processing. Within this review, we go along the process chain of a third generation biorefinery and highlight the process steps which could benefit from laccase applications. Laccases can assist the pretreatment of biomass and promote the subsequent enzymatic hydrolysis of cellulose by the oxidative modification of residual lignin on the biomass surface. In combination with mediator molecules laccases are often reported being able to catalyze the depolymerization of lignin. Studies with lignin model compounds confirm the chemical possibility of a laccase-catalyzed cleavage of lignin bonds, but the strong polymerization activity of laccase counters the decomposition of lignin by repolymerizing the degradation products. Therefore, it is a key challenge to shift the catalytic performance of laccase towards lignin cleavage by optimizing the process conditions. Another field of application for laccases is the detoxification of biomass hydrolyzates by the oxidative elimination of lignin-derived phenolics which inhibit hydrolytic enzymes and are toxic for fermentation organisms. This review critically discusses the potential applications for laccases in biorefinery processes and emphasizes the challenges and perspectives which go along with the use of this enzyme for the technical utilization of lignocellulose.