Article
Polymer Science
Yi-Fang Lee, Tzong-Ming Wu
Summary: The study successfully fabricated a UV protection additive, 1,6-hexanediamine modified layered zinc phenylphosphonate (m-PPZn), for acrylic acid-grafted poly(butylene carbonate-co-terephthalate) (g-PBCT). The g-PBCT polymer matrix was intercalated into the interlayer spacing of m-PPZn, which showed enhanced UV protection ability compared to the pure g-PBCT polymer matrix. The results indicated that the g-PBCT/m-PPZn composites had lower carbonyl index and molecular weight after photodegradation, owing to the better UV reflection ability of m-PPZn.
Article
Polymer Science
Priya Bisht, Krishna K. Pandey, Harish C. Barshilia
Summary: Transparent wood composite (TWC) is a promising material with good optical and mechanical properties, suitable for applications in smart windows, energy efficient building elements, and solar energy concentrators. The study found that TWC is highly sensitive to UV light exposure, showing rapid photo-discolouration, chemical degradation, and a decrease in optical transmittance, requiring the incorporation of UV absorber to reduce degradation for outdoor applications.
POLYMER DEGRADATION AND STABILITY
(2021)
Article
Materials Science, Characterization & Testing
Robert Heidrich, Anton Mordvinkin, Ralph Gottschalg
Summary: The reliability of polymeric encapsulants is ensured by using appropriate additives, particularly UV absorbers and UV stabilizers, to protect them from solar radiation. This study presents a new method for quantitative additive characterization using pyrolysis-gas chromatography-mass spectrometry (PY-GCMS), which allows for qualitative analysis and additive quantification based on solvent-free sample preparation. The method was validated using polymer film samples with different additive concentrations, demonstrating the ability to detect all admixed additives. Calibration with reference samples was required due to the different desorption behavior of UV protecting additives dissolved in n-hexane compared to those bound inside the polymer matrix. The accurate determination of mass fractions of UV absorber and UV stabilizer was achieved using verification samples and a commercial polymer film. The methodology developed in this work is likely applicable to other encapsulants and additive compositions.
Article
Biophysics
Polina Naidjonoka, Marco Fornasier, David Palsson, Gregor Rudolph, Basel Al-Rudainy, Sergio Murgia, Tommy Nylander
Summary: This study reported cubosomes stabilized by two types of softwood hemicelluloses for the first time, showing that SSL-extracted hemicellulose yields the most stable cubosomes based on monoolein (GMO) without significantly affecting their size, morphology, and inner structure. The stability of these particles was also tested under physiological conditions relevant to possible application as drug carriers, indicating their potential in nanomedicine platforms.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2021)
Article
Plant Sciences
Han Jiang, Yueting Pan, Jiawen Liang, Yinghui Yang, Qi Chen, Meiqi Lv, Lu Pang, Weihua He, Xingjun Tian
Summary: The importance and mechanism of UV radiation on litter decomposition in humid forest ecosystems, especially on standing litter, remain unclear. This study found that UV radiation increased the net mass loss of litter by 106.67% in a humid subtropical forest, mainly through microbial degradation.
JOURNAL OF ECOLOGY
(2022)
Article
Environmental Sciences
Hasan Sadeghifar, Arthur Ragauskas
Summary: Lignin, a by-product of pulping and bio-refinery with phenolic chemical structure, has potential as a natural antioxidant, UV blocker, antibacterial and toxic material absorbent. Its antioxidant activity is mainly determined by the presence of phenolic hydroxyl groups, and other structural features and functional groups also affect its antioxidant power. Lignin can improve the thermal stability of synthetic polymers when mixed with them. It has high UV light absorbing potential in broad-spectrum and can provide excellent sun protection when added to hand cream. Lignin also shows strong UV light protection in different transparent films and can protect paint, oil, and varnish from UV degradation. Modified lignin, such as lignosulfonate and lignin hydrogel, have potential as heavy metal absorbers.
Review
Chemistry, Multidisciplinary
Yi Zhang, Maryam Naebe
Summary: Lignin is a promising UV-shielding material with excellent properties, but its dark color can be undesirable in composites. Recent research focuses on developing light-colored UV-shielding composites containing lignin, exploring UV absorption mechanisms, and discussing factors influencing lignin's UV-shielding properties.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Polymer Science
Run-Meng Qiao, Chi-Peng Zhao, Jia-Lei Liu, Mao-Lin Zhang, Wen-Qing He
Summary: In this study, three new tropolone-based UV absorbers were designed and blended into PBAT to prolong its functional period. Among them, UVA-6C exhibited the strongest UV absorbance. PBAT/UVA-6C film showed an extended validity period in the Xenon lamp aging machine and a prolonged functional period during the field application test. The maize yield was significantly increased under PBAT/UVA-6C film compared to pure PBAT film.
Article
Microbiology
Bei Yao, Xiaoyi Zeng, Lu Pang, Xiangshi Kong, Kai Tian, Yanli Ji, Shucun Sun, Xingjun Tian
Summary: Solar radiation plays a crucial role in the decomposition of litter in arid and semiarid ecosystems. However, the specific chemical changes in organic carbon triggered by solar radiation and water pulses have not been well understood. In this study, we investigated the chemical components of marcescent Lindera glauca leaf litter exposed to different types of radiation and water pulses. We found that UV radiation primarily affected the degradation of lignin methoxyl carbon, while PAR and UV radiation combined with water pulses had a significant impact on cellulose oxidation and leaching. The ratio of aromatic carbon to O-alkyl carbon was a robust indicator of mass loss, while the hydrophobicity, carbohydrate to methoxyl carbon ratio, and alkyl carbon to O-alkyl carbon ratio were influenced by water pulses. Additionally, the interaction between radiation and water pulses promoted the activities of peroxidase and phenol oxidase, which are involved in lignin degradation. Our results suggest that the direct photodegradation of lignin methoxyl carbon can enhance microbial accessibility to lignin aromatic carbon and that photo-oxidized compounds may contribute to the stability of the soil carbon pool derived from plant litter.
Article
Nanoscience & Nanotechnology
Dawei Wang, Haiyan Yang, Jing Yang, Bin Wang, Priyanka Wasnik, Ben Bin Xu, Zhengjun Shi
Summary: Degradation of environmental pollutants using renewable solar energy is a low-cost and promising technology, exemplified by the photocatalytic activity of Ag/CuO composites towards organic pollutants. The composites showed excellent performance in degrading alkali lignin, achieving over 94% total organic carbon (TOC) removal under visible light irradiation. Factors such as H2O2 dosage and initial pH were found to influence the photodegradation efficiency of alkali lignin, and a reasonable mechanism for the process was proposed based on experimental results.
ADVANCED COMPOSITES AND HYBRID MATERIALS
(2023)
Article
Agricultural Engineering
Daiqi Fan, Jiaxing Chen, Miqiu Kong, Yadong Lv, Yajiang Huang, Guangxian Li
Summary: In this study, lignin nanoparticles produced from enzymatic hydrolysis lignin were demonstrated as an effective and multifunctional stabilizer for polypropylene. The addition of lignin nanoparticles significantly improved the thermal and photo-oxidation stability of polypropylene, reducing its oxidation degree and suppressing UV degradation.
INDUSTRIAL CROPS AND PRODUCTS
(2022)
Article
Pharmacology & Pharmacy
Haresh T. More, Dilbir S. Bindra, Alexandra Zumba, Kaimeng Zhou, Thiago Carvalho, Rao Mantri
Summary: In this study, it was found that therapeutic proteins, such as monoclonal antibodies (mAbs), are exposed to ambient light conditions during manufacturing and handling processes. The RT/RL stability studies are generally conducted to determine the allowable exposure time. However, an unexpected increase in protein aggregation was observed during a formal RT/RL study due to differences in the setup of the stability chamber. This study emphasizes the importance of understanding UV levels and using representative light conditions for accurate stability assessment of biologic drug products.
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
(2023)
Article
Materials Science, Paper & Wood
M. C. Anish, B. N. Giridhar, Sreeja Nair, N. S. Anantha, Krishna K. Pandey
Summary: Thermal modification is a chemical-free process that improves the hydrophobicity, dimensional stability, and biological durability of wood. This study found that thermally modified wood showed enhanced resistance to UV degradation, potentially due to the accumulation of extractives and the generation of photostable compounds during the thermal modification process.
WOOD MATERIAL SCIENCE & ENGINEERING
(2023)
Article
Engineering, Environmental
Maria Eugenia Taverna, Luisina Beatriz Bressan, Carlos Alberto Busatto, Maia Raquel Lescano, Diana Alejandra Estenoz
Summary: This study investigates the preparation of composite poly(lactic acid)/lignin microparticles and their characterization through various techniques. The results demonstrate that a higher lignin content improves the encapsulation efficiency of the biopesticide, while a higher poly(lactic acid) content leads to a lower release rate and less photodegradation. Therefore, the biopolymer blend shows promising potential for microparticle preparation to encapsulate and protect biopesticides against degradation.
JOURNAL OF POLYMERS AND THE ENVIRONMENT
(2023)
Article
Chemistry, Multidisciplinary
Binpeng Zhang, Dongjie Yang, Wensheng Lin, Huan Wang, Yong Qian, Xueqing Qiu
Summary: Quaternized alkali lignin (QAL) was successfully synthesized and used as a carbon precursor to fabricate lignin-derived carbon/TiO2 (LC/TiO2) composite photocatalyst, which exhibited enhanced photocatalytic activity compared to bare TiO2, showing great potential for high value-added application of industrial lignin and practical application of TiO2 photocatalyst.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Saeid Nikafshar, Jiarun Wang, Kevin Dunne, Prakit Sangthonganotai, Mojgan Nejad
Summary: Thirteen unmodified lignin samples from various biomass sources were used to replace bisphenol A (BPA) in epoxy resin formulations using a novel method. It was found that lignins with higher phenolic hydroxy content and lower molecular weights were more suitable for this purpose, and a regression model was developed to establish correlations between lignin properties and epoxy contents. Additionally, epoxidized lignin samples with high epoxy contents showed comparable performance to a petroleum-based epoxy system when cured with a bio-based hardener.
Article
Chemistry, Applied
Saeid Nikafshar, John McCracken, Kevin Dunne, Mojgan Nejad
Summary: Epoxy coatings are widely used for their excellent properties, but are susceptible to UV degradation. This study developed a new method to encapsulate organic UV stabilizers and lignin into halloysite nanotubes for improving UV stability. The encapsulated nanotubes showed significantly higher UV stability compared to individual components when added to epoxy resin.
PROGRESS IN ORGANIC COATINGS
(2021)
Article
Materials Science, Multidisciplinary
Gabrielly dos Santos Bobadilha, C. Elizabeth Stokes, Katie M. Ohno, Grant Kirker, Dercilio Junior Verly Lopes, Mojgan Nejad
Summary: The demand for cross-laminated timber (CLT) is increasing in the United States, but adequate protective measures for exterior wood coatings have not been extensively studied. Only two out of five coatings showed adequate performance after twelve months of field exposure, with location and coating type influencing the aging of samples.
Article
Biochemistry & Molecular Biology
Akash Gondaliya, Mojgan Nejad
Summary: This study evaluated the suitability of various lignins in replacing 20% of petroleum-based polyol in PU foams, finding that the incorporation of lignin improved the foam's mechanical properties. The study also showed a positive correlation between lignin's hydroxyl content and foam properties, suggesting lignins with low hydroxyl content, high flexibility, and high solubility are better candidates for replacing petroleum-based polyols in flexible PU foams.
Article
Engineering, Chemical
Graham W. Tindall, Spencer C. Temples, Mikhala Cooper-Robinson, Villo Eniko Becsy-Jakab, David B. Hodge, Mojgan Nejad, Mark C. Thies
Summary: Under specific conditions, aqueous organic solvents can dissolve lignin to form a liquid phase separate from the solvent, creating liquid-liquid equilibrium. The formation of liquid-liquid equilibrium with alcohol solutions offers new opportunities for large-scale purification of raw lignins.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Biochemistry & Molecular Biology
Christian Henry, Akash Gondaliya, Mark Thies, Mojgan Nejad
Summary: In this study, 19 unmodified lignins from various sources and isolation processes were used to replace petroleum-based polyol in foam formulations. The properties of the resulting lignin-based foams were compared with a control foam. It was found that lignin-based foams with higher pH, potassium, sodium, calcium, magnesium, and aliphatic/p-hydroxyphenyl hydroxyl group contents exhibited better performance.
Article
Chemistry, Multidisciplinary
Mohsen Siahkamari, Sasha Emmanuel, David B. Hodge, Mojgan Nejad
Summary: In this study, a biobased phenolic adhesive was developed by replacing petroleum-based phenol and formaldehyde with unmodified corn stover biorefinery lignin and glyoxal. The synthesized lignin-glyoxal resin showed higher molecular weight than the starting lignin, indicating successful integration. The adhesive demonstrated high dry adhesion strength and stability in room temperature water.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Peng Quan, Alper Kiziltas, Akash Gondaliya, Mohsen Siahkamari, Mojgan Nejad, Xinfeng Xie
Summary: A one-pot acid-catalyzed liquefaction method was developed to recover Kraft lignin directly from black liquor, achieving a high recovery rate. The recovered lignin showed improved homogeneity and was successfully used in flexible polyurethane foams by adjusting its molecular weight characteristics. This study provides a promising approach to recover lignin with customized properties for downstream processes.
Article
Forestry
Sajad Bagheri, Mona Alinejad, Katie Ohno, Laura Hasburgh, Rachel Arango, Mojgan Nejad
Summary: This study used borate solution to treat Douglas-fir wood samples and developed a model to predict borate uptake under different treatment parameters. The results showed that both spray- and dip-treated samples exhibited improved termite, decay resistance, and fire performance.
JOURNAL OF WOOD SCIENCE
(2022)
Article
Agriculture, Multidisciplinary
Brian K. Saulnier, Mohsen Siahkamari, Sandip K. Singh, Mojgan Nejad, David B. Hodge
Summary: This study evaluated the impact of pretreatment conditions on lignin extractability, properties, and utility in wood phenol-formaldehyde (PF) adhesives by subjecting corn stover to dilute sulfuric acid pretreatment. The findings showed that both formic acid and NaOH could extract and recover a significant amount of lignin after pretreatment and enzymatic hydrolysis, while still achieving reasonable enzymatic hydrolysis yields. The availability of reaction sites for lignin incorporation into the PF polymer matrix was strongly influenced by the pretreatment time and recovery. Additionally, a lignin-based wood adhesive was developed by replacing phenol with formic-acid-extracted lignin, which exhibited superior dry shear strength compared to conventional PF adhesives.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2022)
Article
Engineering, Chemical
Christian Henry, Mojgan Nejad
Summary: In this study, unmodified kraft softwood lignin was used to replace petroleum-based polyol in low-density rigid polyurethane/polyisocyanurate foam. Different levels of lignin incorporation were investigated for their effects on foam properties. The foam made with 100% lignin demonstrated outstanding fire resistance, reducing burn length by 127%.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Materials Science, Composites
Sajad Bagheri, Mojgan Nejad
Summary: In this study, petroleum-based bisphenol A (BPA) was entirely replaced by unmodified kraft softwood lignin in epoxy resin formulation. Epoxidized lignin was prepared and confirmed by measuring the epoxy content using titration and Fourier-transform infrared spectroscopy (FTIR). A fully biobased epoxy resin was prepared by mixing the epoxidized lignin with a biobased curing agent. The addition of bamboo fibers improved the flexural strength and modulus of the lignin-based epoxy composite.
POLYMER COMPOSITES
(2023)
Article
Polymer Science
Christian Henry, Graham Tindall, Mark C. Thies, Mojgan Nejad
Summary: This study explores the use of fractionated lignin as a component in the formulation of rigid PUR/PIR foams. Both hybrid poplar lignin and ALPHA-fractionated lignin were used as substitutes for petrochemical-based polyol in low-density foams. The ALPHA-based lignin outperformed the as-recovered lignin in terms of foam properties, and showed comparable performance to the control foam.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Julie M. Rieland, Saeid Nikafshar, Zeyuan Hu, Mojgan Nejad, Brian J. Love
Summary: This paper reports the dissolution and shaping of cotton and coffee fruit (cascara) in 1,8-diazabicyclo[5.4.0]undec-7-inium acetate ([DBUH][OAc]). It is found that [DBUH][OAc] can dissolve both cotton and coffee fruit, and coffee fruit solution can form fibers at lower concentrations. The composition and properties of cascara and cotton are compared, indicating that cascara has higher lignin content and weaker mechanical strength. This study explores the use of ionic liquids as solvents for separating coffee fruit residues and extracting fibers and biopolymers.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2023)
