Search Results (38)

Rosin, a renewable natural resin derived from pine trees, is a promising biomass material for sustainable product development, though its distinct intrinsic odor limits broader use. This study implemented a comprehensive analytical strategy to mitigate the odor by incorporating essential oils (EOs)—eucalyptus (EUC) and peppermint (MINT)—and to conduct a multi-analytical characterization of the modified rosin jewelry. By integrating complementary analytical techniques, including LC-Q/TOF-MS for non-volatile components and GC-Q/TOF-MS for volatile organic compounds (VOCs), we achieved a systematic chemical profiling of the materials. The core composition of rosin, dominated by abietic acid (>48%), remained stable across all samples. The incorporation of EOs significantly altered the VOC profiles: The total VOC signal (summed peak area) in MINT-modified rosin was 2.57-fold that of the EUC-modified sample, with monoterpenoids comprising 87.62% of its VOC signature. Eucalyptol and limonene were tentatively identified as the major components in the EUC sample, whereas menthone, menthol, and limonene predominated in the MINT sample. Multivariate statistical analysis highlighted that variations in specific VOCs—particularly menthone, menthol, eucalyptol, and allo-ocimene—were closely associated with differences in the scent profiles of each modification. This work illustrates how a multi-technique analytical strategy can both guide and assess the functional modification of sustainable biomass materials. The findings offer a practical approach to improving rosin’s functional properties while providing a methodological framework for the integrated characterization of complex biomaterials, supporting the development of eco-friendly products aligned with green chemistry and sustainable design principles. Full article

The design of sustainable polymer systems with tunable properties is essential for next-generation functional materials. This study examines the influence of a phenol-free modified rosin resin (Unik Print™ 3340, UP)—a maleic anhydride- and fumaric acid-modified gum rosin—on the structural, thermal, rheological, and mechanical behavior of four poly(lactic acid) (PLA) grades with different molecular weights and crystallinity. Blends containing 3 phr of UP were prepared by melt compounding. Thermogravimetric analysis showed that the incorporation of UP did not alter the thermal degradation of PLA, confirming stability retention. In contrast, differential scanning calorimetry revealed that UP affected thermal transitions, suppressing crystallization and melting in amorphous PLA grades and shifting the crystallization temperature to lower values in semi-crystalline grades. The degree of crystallinity decreased for low-molecular-weight semi-crystalline PLA but slightly increased in higher-molecular-weight samples. Mechanical tests indicated that UP acted as a physical modifier, increasing toughness by over 25% for all PLA grades and up to 60% in the amorphous, low-molecular-weight grade. Rheological measurements revealed moderate viscosity variations, while FESEM analysis confirmed microstructural features consistent with improved ductility. Overall, UP resin enables fine tuning of the structure–property relationships of PLA without compromising stability, offering a sustainable route for developing bio-based polymer systems with enhanced mechanical performance and potential use in future biomimetic material designs. Full article

Wood modification using biopolymers has emerged as a sustainable alternative to conventional chemical treatments, enhancing wood’s durability, moisture resistance, and mechanical properties while reducing environmental impact. This review provides a comprehensive overview of the latest advancements in biopolymer-based wood modification, focusing on commonly used biopolymers such as furfuryl alcohol, polylactic acid, caprolactone, polybutylene adipate terephthalate, polybutylene succinate, zein, lignin, tannin, chitosan, alginate, gums, fatty acids, rosin, and sorbitol + citric acid. Future perspectives highlight the need for interdisciplinary collaboration between academia, research institutions, and industry to accelerate innovation and commercialization. This review aims to provide valuable insights for researchers and industry professionals working toward the development of high-performance, eco-friendly modified wood products. Full article

This review comprehensively explores natural polymer-based materials, focusing on their characteristics, applications, and innovations across different sectors, including medicine, the environment, energy, textiles, and construction. With increasing concern about resource depletion and pollution, biomaterials offer a sustainable alternative to fossil-derived products. The review highlights polysaccharide-based and protein-based biomaterials, as well as others, such as polyisoprene, rosin, and hyaluronic acid. Emphasis is laid on their compositions and attractive characteristics, including biocompatibility, biodegradability, and functional versatility. Moreover, the review deeply discusses the ability of natural polymers to form hydrogels, aerogels, films, nanocomposites, etc., enhanced by additives for innovative applications. Future development trends of biomaterials in biomedicine, sustainable materials, environmental biotechnology, and advanced manufacturing are also explored. Their growing potential in these sectors is driven by research advances in emerging technologies such as 3D bioprinting, nanotechnology, and hybrid material innovation, which are proven to enhance the performance, functionality, and scalability of biopolymers. The review suggests several strategies, including improvement in processing techniques and material engineering to overcome limitations associated with biomaterials, thereby reinforcing their suitability and role in a circular and sustainable economy. Full article

Dehydroabietic acid (DHA) is a secondary metabolite isolated from rosin, which has certain antifungal activity, but its inhibitory effects against Alternaria alternata are unclear. In the present study, we found that DHA inhibited the mycelial growth of A. alternata, Botrytis cinerea, Valsa mali, Pestalotiopsis neglecta, and Fusarium oxysporum in a concentration-dependent manner, with the best inhibitory effect against A. alternata. Moreover, DHA can also inhibit the spore germination of A. alternata. Then, in vivo inoculation experiments showed that the leaf lesions of Populus alba gradually decreased with the increase in DHA concentration. The disease of P. alba leaves inoculated with A. alternata was not obvious after treatment with 800 mg/L DHA. The scanning electron microscopy showed that the mycelial morphology was abnormal, with crinkles and depressions. Meanwhile, the relative conductivity, soluble protein content, malondialdehyde content and hydrogen peroxide content of A. alternata were significantly increased after DHA treatment, which affected the integrity of the cell membrane and increased the permeability of A. alternata, resulting in a large leakage of intracellular substances, exacerbating the degree of lipid peroxidation of the cell membrane of A. alternata and causing oxidative damage to cells. The enzyme activity assay showed that treatment with 56.015 mg/L (EC₅₀) DHA significantly reduced the activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase) and cell-wall-degrading enzymes (endoglucanase, polygalacturonase, pectin lyase) in A. alternata (p < 0.05), resulting in a decrease in the activity of pathogenic fungi, as well as a reduction in the ability of the A. alternata to degrade the cell wall of the host plant, which led to a decrease in the ability of the A. alternata to infest the host plant. Moreover, the decrease in the relative expression of defense-related enzyme genes (AaSOD, AaPOD, AaCAT) and pathogenicity-related enzyme genes (AaPL, AaPG) was consistent with the enzyme activity results. Thus, the present study revealed the fungicidal activity and mechanism of DHA against A. alternata and the potential of DHA to be developed as a plant-derived antifungal agent was established. Full article

In Mexico, there is a deficit in the production of pine resin, because it relies on natural forests only. Therefore, it is necessary to select provenances and phenotypes of potential species such as P. oocarpa. The objective was to determine the difference between provenances and the variation in resin components and quality, as well as the effect of geographic and climatic factors. Resin from five provenances was collected from southern Mexico. The percentage of rosin, turpentine and water was obtained, as well as the acidity and saponification index. P. oocarpa resin had 80.94% rosin, 7.7% turpentine and 11.49% water. The saponification and acidity index was 125.47 and 117.49 mg KOH.g⁻¹, respectively. All variables showed differences (p ≤ 0.0001) between provenances. The provenance contributed between 6.44 and 11.71% to the total variance, the error contributed between 88.29 and 93.56%. Geographic and climatic variables only had an effect on the percentage of turpentine; the correlation was negative with altitude and longitude, but positive with temperature and precipitation. The results allow defining seed collection sites for resin plantations and orienting the selection for a P. oocarpa improvement program. Full article

Leakage is a high-incidence disease of embankment dams, and efficiently addressing this disease guarantees the safe operation of dams. Underwater leakage self-priming plugging technology is a new technology that utilizes the melting and solidifying characteristics of phase-change materials and the negative pressure in the leakage entry area to accurately plug the leakage. However, little is yet known about the underwater melting process of phase-change materials and how their characteristics influence the plugging effect. In this study, three kinds of phase-change materials, namely, paraffin, rosin, and stearic acid, were used to conduct underwater leakage self-priming plugging tests, observe and analyze the underwater melting process, and compare the plugging effects. The results showed that the underwater melting process of phase-change materials exhibited different plugging window periods depending on their melting points, specific heat capacities, and mobilities, which were the main factors affecting their plugging effects. In the final plugging stage, paraffin had the best plugging effect, but the material strength was low; rosin had good plugging compactness, but the fluidity performance was poor, and the material effective utilization was low; stearic acid had a low melting point but dispersed easily. Therefore, a blocking material with a suitable blocking window period can be produced by adjusting the material properties accordingly for an improved blocking effect. Full article

The production of wheat straw waste board materials encounters challenges, including inadequate inherent adhesiveness and the utilization of environmentally harmful adhesives. Employing a hot-pressed method for converting wheat straw into board materials represents a positive stride towards the resourceful utilization of agricultural wastes. This study primarily focuses on examining the influence of hot-pressing process conditions on the mechanical properties of wheat straw board materials pretreated with dilute acid. Additionally, it assesses the necessity of dilute acid treatment and optimizes the hot-pressing conditions to achieve optimal results at 15 MPa, 2 h, and 160 °C. Furthermore, a comprehensive process is developed for preparing wheat straw hot-pressed board materials by combining dilute acid pretreatment with surface modification treatments, such as glutaraldehyde, citric acid, and rosin. Finally, a thorough characterization of the mechanical properties of the prepared board materials is conducted. The results indicate a substantial improvement in tensile strength across all modified wheat straw board materials compared to untreated ones. Notably, boards treated with glutaraldehyde exhibited the most significant enhancement, achieving a tensile strength of 463 kPa, bending strength of 833 kPa, and a water absorption rate of 14.14%. This study demonstrates that combining dilute acid pretreatment with surface modification treatments effectively enhances the performance of wheat straw board materials, offering a sustainable alternative to traditional wood-based board materials. Full article

Herein, a phenomenological kinetic modeling of the disproportionation of rosin with a well-known antioxidant and bleaching agent, antioxidant 300, also known as 4,4′-thio-bis(3-methyl-6-tert-butylphenol) under thermal conditions adequate for rosin esterification with polyols such as glycerol or pentaerythritol, is studied. The temperature was varied in the 260–280 °C range, while the catalyst was either absent or added till a 2% w/w amount relative to rosin. The composition of the reaction liquid was followed by GC-MS to identify the rosin acids present in each sample and GC-FID to quantify them. Gas chromatography analyses indicated that abietic acids were involved in dehydrogenation, isomerization and disproportionation reactions, while pimaric acid underwent a number of isomerization reactions, dehydroabietic acid being the main product of the disproportionation process, while abietic acid almost disappeared in the more reactive conditions. Several kinetic models featuring direct hydrogenation, disproportionation, isomerization, and dehydrogenation reactions were proposed and fitted, step by step, to all relevant data. Physicochemical and statistical discrimination allowed for the selection of the most adequate model, which includes abietic, neoabietic and palustric acid dehydrogenation to dehydroabietic acid, abietic acid disproportionation to di- and dehydroabietic acid, and pimaric acid isomerization. In any case, a model with isomerization of all abietic-type acids towards abietic acid before its further transformation via dehydrogenation and disproportionation reactions seems statistically valid as well. Full article

Gum rosin is an important agricultural commodity which is widely used as a raw material for various industries. However, gum rosin has low stability, crystallizes easily, and tends to oxidize. This is due to carboxyl groups and conjugated double bonds in gum rosin’s structure. Therefore, to reduce these weaknesses, it is necessary to modify the rosin compound to achieve better stability via the esterification process. This paper surveys esterification agents such as glycerol, pentaerythritol, methanol, ethylene glycol, polyethylene glycol (PEG), allyl group, and starch Rosin ester. The product is used in the manufacture of pressure-sensitive adhesives, drug delivery, solder flux for electronic devices, as a plasticizer, and as a coating agent in fertilizers. In general, the esterification reaction between alcohols and carboxylic acids is very slow without a catalyst. Heterogeneous catalysts have the advantage of controlling size, structure, spatial distribution, surface composition, thermal-chemical stability, and selectivity. Among the catalysts for gum rosin esterification are ZSM-5, Fe₃O₄, ZnO, Calcium, TiO₂, Kaolin, and Al₂O₃, among others. Different catalysts and esterification agents can produce various physical and chemical properties of rosin ester and will result in specific rosin ester products, such as glycerol ester, pentaerythritol ester, methyl ester, glycol ester, allyl ester, and acid starch-based rosin. Full article

This study aims to reveal the effects of flexible chain lengths on rosin-based epoxy resin’s properties. Two rosin-based epoxy monomers with varying chain lengths were synthesized: AR-EGDE (derived from ethylene glycol diglycidyl ether-modified acrylic acid rosin) and ARE (derived from acrylic acid rosin and epichlorohydrin). Diethylenetriamine (DETA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA) with different flexible chain lengths were used as curing agents. The adhesion, impact, pencil hardness, flexibility, water and heat resistance, and weatherability of the epoxy resins were systematically examined. It was found that when the flexible chains of rosin-based epoxy monomers were grown from ARE to AR-EGDE, due to the increased space of rosin-based fused rings, the toughness, adhesion, and water resistance of the rosin-based epoxy resins were enhanced, while the pencil hardness and heat resistance decreased. However, when the flexible chains of curing agents were lengthened, the resin’s performance did not change significantly because the space between the fused rings changed little. This indicates that the properties of the rosin-based resins can only be altered when the introduced flexible chain increases the space between the fused rings. The study also compared rosin-based resins to E20, a commercial petroleum-based epoxy of the bisphenol A type. The rosin-based resins demonstrated superior adhesion, water resistance, and weatherability compared to the E20 resins, indicating the remarkable durability of the rosin-based resin. Full article

Pine rosin, which is derived from Pinus merkusii resin, a natural product, has demonstrated potential as a road marking binder. Although pine rosin has an excellent shinning property, it has some limitations, such as instability and color change. To tackle these issues, modified rosin has been developed through sequential esterification and Diels–Alder reactions, and it has shown better properties than untreated rosin. In this study, from the evaluation of untreated and treated rosins, the treated rosin showed some improvements, such as a lower acid value and higher stability, as shown by the color consistency during the oxidation test at 150 °C for 24 h in open-air conditions. Additionally, as road marking paint, the modified rosin is blended with blending materials in the range of 18–28 wt.%. The modified rosin has a softening point of 170–210 °C, a hardness of 50–71 HD, and a weight loss of 1.33–5.12 mg during the wearing test. These results are comparable to or better than those of commercially available road marking products. Full article

Vegetable-oils-based pressure-sensitive adhesives (PSAs) are being developed as a substitute for petrochemical-based PSAs for application in daily life. However, vegetable-oils-based PSAs face the problems of unsatisfactory binding strengths and easy aging. In this work, the grafting of antioxidants (tea polyphenol palmitates, caffeic acid, ferulic acid, gallic acid, butylated hydroxytoluene, tertiary butylhydroquinone, butylated hydroxyanisole, propyl gallate (PG), tea polyphenols) was introduced into an epoxidized soybean oils (ESO)/di-hydroxylated soybean oils (DSO)-based PSA system to improve the binding strengths and aging-resistant properties. PG was screened out as the most suitable antioxidant in the ESO/DSO-based PSA system. Under optimal conditions (ESO/DSO mass ratio of 9/3, 0.8% PG, 55% rosin ester (RE), 8% phosphoric acid (PA), 50 °C, and 5 min), the peel adhesion, tack, and shear adhesion of the PG-grafted ESO/DSO-based PSA increased to 1.718 N/cm, 4.62 N, and >99 h, respectively, in comparison with the control (0.879 N/cm, 3.59 N, and 13.88 h), while peel adhesion residue reduced to 12.16% in comparison with the control (484.07%). The thermal stability of the ESO/DSO-based PSA was enhanced after PG grafting. PG, RE, PA, and DSO were partially crosslinked in the PSA system, with the rest being free in the network structures. Thus, antioxidant grafting is a feasible method for improving the binding strengths and aging-resistant properties of vegetable-oils-based PSAs. Full article

As an important forestry biomass resource, rosin has a wide range of applications in medicine, adhesives, surfactants and other fields. Using natural dehydroabietic acid as a raw material, dehydroabietic acid-based phosphorus monoester (DPM) and diester (DPD) surfactants were designed and synthesized. The chemical structures and self-assembly properties were characterized by FT-IR, NMR and TEM, and the effects of pH on critical micelle concentration, γ_CMC, emulsifying properties, foam properties and micelle morphology were studied. The results showed that the CMC, γ_CMC value and aggregate morphology had certain pH responsiveness. The γ_CMC value under acidic conditions was smaller than γ_CMC under alkaline conditions, and the foaming performance and foam stability under acidic conditions were better than those under alkaline conditions. TEM micelle morphology studies have shown that DPM and DPD surfactants can self-assemble into rod-shaped and spherical micelle morphologies with a pH change in an aqueous solution. At the same pH, the foaming and emulsification properties of DPD were better than those of DPM. The best foaming and emulsification ability of DPD were 11.8 mL and 175 s, respectively. At the same time, the foaming ability of DPD is also affected by pH. DPD has excellent foaming properties in acidic conditions, but these disappeared in neutral conditions. Full article

Abietic acid (AA) is known to have beneficial effects on inflammation, photoaging, osteoporosis, cancer, and obesity; however, its efficacy on atopic dermatitis (AD) has not been reported. We investigated the anti-AD effects of AA, which was newly isolated from rosin, in an AD model. To achieve this, AA was isolated from rosin under conditions optimized by response surface methodology (RSM), and its effects on cell death, iNOS-induced COX-2 mediated pathway, inflammatory cytokine transcription, and the histopathological skin structure were analyzed in 2,4-dinitrochlorobenzene (DNCB)-treated BALB/c mice after treatment with AA for 4 weeks. AA was isolated and purified through isomerization and reaction-crystallization under the condition (HCl, 2.49 mL; reflux extraction time, 61.7 min; ethanolamine, 7.35 mL) established by RSM, resulting in AA with a purity and extraction yield of 99.33% and 58.61%, respectively. AA exhibited high scavenging activity against DPPH, ABTS, and NO radicals as well as hyaluronidase activity in a dose-dependent manner. The anti-inflammatory effects of AA were verified in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages through amelioration of the inflammatory response, including NO production, iNOS-induced COX-2 mediated pathway activation, and cytokine transcription. In the DNCB-treated AD model, the skin phenotypes, dermatitis score, immune organ weight, and IgE concentration were significantly ameliorated in the AA cream (AAC)-spread groups compared to the vehicle-spread group. In addition, AAC spread ameliorated DNCB-induced deterioration of skin histopathological structure through the recovery of the thickness of the dermis and epidermis and the number of mast cells. Furthermore, activation of the iNOS-induced COX-2 mediated pathway and increased inflammatory cytokine transcription were ameliorated in the skin of the DNCB+AAC-treated group. Taken together, these results indicate that AA, newly isolated from rosin, exhibits anti-AD effects in DNCB-treated AD models, and has the potential to be developed as a treatment option for AD-related diseases. Full article