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In this study, three PEG-maleated rosin polyesters were produced by reacting between maleated rosin and PEG with different molecular weights and served as surfactants. The surface characteristics of these PEG-maleated rosin polyesters were detected. The conformational transition and adsorption characteristics of these polyesters were analyzed with the reorientation theory on the water–air surface. The surfactant mole fraction at the water–air surface increased as surfactant concentration increased, while the solvent mole fraction was decreased. The amount of surfactant on the water–air surface at state 1 with a maximal molar area appeared one unimodal in distribution and that at state 2 occupying a minimal molar area appeared a sigmoid distribution with П growth. The calculated adsorption free energy from CMC value is lower than calculated micellization energy obtained from molecular area at state 2 indicates the polyethylene glycol-maleated rosin polyesters firstly spread on the water–air surface and then aggregated into micelles. The results lay a foundation for better understand the adsorption and self-assembly processes. The adsorption characteristics and conformational transition of three PEG-maleated rosin polyesters were investigated. Paper title: Adsorption Characteristics and Conformational Transition of Polyethylene Glycol-maleated Rosin Polyesters on the Water–Air Surface

Background As one of the most important modified products of rosin, rosin glyceride was widely used in many aspects. However, the preparation of rosin glyceride is always unfriendly due to the use of liquid catalyst, such as H2SO4 and H3PO4. Methods The rosin glyceride with low acid value was synthesized in vacuum conditions using a novel Lewis acidic ionic liquid 1–butyl–3–methylimidazolium chloroscandinate[BuMeim][Sc2Cl7] as catalyst. The [BuMeim][Sc2Cl7] is of excellent catalytic activity and stability. The efficient catalytic activity was studied via the combined Density Functional Theory (DFT) and experimental conditions. Significant findings The DFT proved the free energy of the esterification could reach to 31.6 Kcal/mol, which illuminates that the excellent coordination of the anions and cations in the [BuMeim][Sc2Cl7] greatly reduces the reaction energy barrier and promotes the efficient progress of the reaction. As a result, [BuMeim][Sc2Cl7] is a good catalyst for the esterification of rosin and glycerol to prepare rosin glyceride. Furthermore, [BuMeim][Sc2Cl7] could be a potential catalysts for the other esterification.

Background Colophonium (rosin) can cause allergic contact dermatitis, mainly due to autoxidation of abietic acid (AbA). Products containing ≥0.1% colophonium should be labeled with EUH208 - "Contains rosin; colophony. May produce an allergic reaction." How should this be measured? Objective To compare the results from different strategies for estimating colophonium levels in consumer products: (a) from AbA, and (b) the sum of all major resin acids. To investigate the ratio of 7-oxodehydroabietic acid (7-O-DeA)/AbA as indication of autoxidation. Methods Resin acids were extracted from consumer products, derivatized, and then separated by gas chromatography/mass spectrometry (GC/MS). Results Resin acids were detected in 9 of 15 products. No product contained colophonium ≥0.1%. Estimation based on AbA resulted in underestimation of the colophonium levels in four of nine products. For three products, the obtained levels from this strategy were only one of two compared to when estimating from the sum of all resin acids. The ratio 7-O-DeA/AbA varied from 74% to 1.4%. Conclusions We propose to measure colophonium based on the sum of all detectable major resin acids, including 7-O-DeA. The ratio of 7-O-DeA/AbA should be used as a marker of autoxidation, indicating an increased risk of sensitization. The presented analytical method is simple to use and suitable for further screening studies.

Green renewable resource has become a global hot spot. In this study, naturally occurring resource rosin derivative (RAG) was used to prepared a cationic waterborne polyurethane (WPU) dispersion using n-methyl di-ethanolamine (MDEA) as an ion center and 1,3-bis(3-aminopropyl) tetramethydisiloxane (APTMDS) as a chain extender, and hexamethylene diisocyanate (HDI) as a hard segment. The effects of MDEA and APTMDS contents on the particle size and storage stability of the WPU dispersion was determined, in addition, thermo-mechanical and mechanical properties, and antibacterial property as well as water uptake of the resulting polyurethane films were thoroughly investigated. The results show that an increase in the APTMDS content considerably improved the mechanical properties, surface hydrophobicity and water resistance of the WPU films. Moreover, all WPU films exhibit enhanced antibacterial activity against Escherichia coli and Staphylococcus aureus with the increase in the MDEA and APTMDS contents.

The utilization of rosin to fabricate functional polymers has attracted great attention due to its unique structure and property. Herein, we prepared a new type of carboxyl-containing cross-linked rosin microspheres (CCRMs) using a renewable-resource rosin as the raw material through the suspension polymerization. For comparative purpose, vanillin methacrylate (VMA), styrene (St) and isobornyl methacrylate (IBOMA) were separately used to replace DAGMA as monomer for the preparation of microspheres. Our results indicated that the obtained porous CCRMs showed a broad size distribution ranging from mesopores (3–50 nm) to macropores (> 50 nm), whereas the counterparts derived from VMA, St or IBOMA showed a powder state. Moreover, the CCRMs exhibited moderately high thermal stability. The integration of DAGMA into polymer microspheres provided CCRMs with excellent adsorption ability, which exhibited robust selective cationic dye (e.g., methylene blue (MB) and crystal violet (CV)) adsorption from waste aqueous solution. The adsorption process was fitted well with the Langmuir isotherm and the pseudo-second-order kinetic model. The maximum adsorption capacity was observed to be 602.4 mg/g for CV at 40 °C, and 512.8 mg/g for MB at 20 °C. In general, the high dye adsorption properties suggest that CCRMs may be highly efficient in adsorption selectivity for some cationic dyes.

The effect of adhesive additives of polar and nonpolar nature on the properties of uncurable sealants based on butyl rubber was studied. It has been found that alkylphenol–formaldehyde resins and rosin are effective additives that increase the cohesive and adhesive strength.

To improve the effect of pine rosin in plant fungicides, four series of dehydroabietyl-1,3,4-thiadiazole derivatives from the natural product rosin were synthesized. Based on the evaluation of the in vitro antifungal activity against Sclerotinia sclerotiorum, Botrytis cinerea, Fusarium oxysporum, and Magnaporthe oryzae, rosin-based 1,3,4-thiadiazole compounds containing thiophene heterocycles were screened. Notably, compound 3e [dehydroabietyl-(1,3,4-thiadiazol-2-yl)-5-nitrothiophene-2-carboxamide] exhibited excellent antifungal property against F. oxysporum with an EC50 of 0.618 mg/L, which was lower than that of the positive control carbendazim (0.649 mg/L). The in vivo antifungal activity results showed that 3e exerted a protective effect on cucumber plants. Physiological and biochemical studies showed that the primary mechanism of action of compound 3e on F. oxysporum was it changed the mycelial morphology, increased the cell membrane permeability, and inhibited the synthesis of ergosterol in the mycelia. Furthermore, the quantitative structure-activity relationship studies revealed that the frontier orbital energy in the molecule had a key role in the antifungal activity through the conjugation and electrostatic interaction between compound 3e and the receptors of the target. Thus, the present study highlighted the application of rosin-based fungicidal candidates and exploited efficient plant pesticides for sustainable crop production.

In this study, investigation of the combustion properties of Oriental beech wood (Fagus orientalis Lipsky) impregnated with boron compound (borax (Na2B4O710H2O), boric acid (H3BO3) doped rosin (C19H29COOH) was aimed. For this purpose, Oriental beech wood samples were prepared according to ASTM E 160-50 and impregnated with boron compound doped rosin by the method of medium-term dipping (24 hours) according to ASTM D 1413 and producers’ definition. Combustion properties of samples after impregnated process were determined according to ASTM E 160-50. As a part of the research, 6 different combination and contents of impregnation materials have been used in order to especially investigate resistance against combustion of wood material treated with boron compounds in different concentrations. As a result of the study, retention performance and leaching resistance of boron compounds can be increased through rosin addition. Consequently, impregnation materials with rosin decreased the flame sourced combustion (Fsc) temperatures depending on kind of impregnation material, extended combustion period and decreased weight loss ratio of the test samples in comparison to the control samples. On the contrary, weight loss ratios were affected negatively in Oriental beech test samples up to 3% when compared with samples which were impregnated with borax. Meanwhile, combustion periods increased in test samples up to 30%. Rosin, in terms of its combustion performance, can be preferred in impregnation with boron compounds depending on kind of wood and using area.

The objective of present investigation was to synthesize and assess sub-acute toxicity of novel rosin esters using Swiss Albino mice. Assessment of the safety and toxicity of rosin esters is very important step before its use in pharmaceuticals. The solutions of rosin esters were prepared in corn oil to perform acute (28d) oral toxicity study in Swiss Albino mice as animal model of both sexes. The oral administration of rosin esters at the dose of 25 mg/kg of body weight and constant volume was administered to the mice. One group of mice was kept as a control group. Toxicity of the rosin esters was assessed by using various tests like behavioral changes, clinical signs, mortality and morbidity, biochemical tests, haematological tests, relative organ weights and histopathology tests. The body weights and food-water consumption by mice were recorded on weekly basis. The study results revealed that, there were no signs and incidences of toxicity or mortality in mice during the study period. No significant difference between treated (rosin ester administered) and control group of mice were recorded in the observations of different tests, body weights and food-water consumption. The histopathological examination of organs from the mice treated with rosin esters for 28d does not show any signs of toxic effects when compared with the control group. Therefore, the present investigation confirmed the non-toxic nature of novel rosin ester at 25mg/kg daily dose of body weight after oral administration in both the sexes.

In this article, gum rosin-based hyperbranched vinyl ester resin (VPEMPAE) was synthesized from maleic anhydride-modified gum rosin adduct (MPA). This adduct (MPA) was reacted with pentaerythritol to obtain esterified adduct (PEMPA). The PEMPA adduct was epoxidized using epichlorohydrin and KOH as a catalyst to give epoxy resin (PEMPAE). The epoxide rings were then reacted with methacrylic acid to synthesize vinyl ester resin (VPEMPAE). The lignin modeled compounds (LMCs), methacrylated eugenol (ME), and methacrylated guaiacol (MG) were used as bio-based reactive monomers for vinyl ester resin. The chemical structures of all the products were studied using FT-IR, 1H-NMR, 13C-NMR, and DEPT-135° spectroscopic analysis. The dynamic curing study of cured samples was done using DSC. Thermogravimetric analysis of these samples was performed using TGA at a heating rate of 10 °C min−1. Mechanical properties such as compression, flexural, and tensile strengths of VPEMPAE samples were also determined using a universal testing machine. Some preliminary coating tests were also performed to determine the chemical resistance of these cured resins and morphological studies on these coatings were also conducted using SEM. The results of this study showed better performance of rosin-derived vinyl ester resin cured with reactive diluent ME as compared to MG and commercially based styrene.

Rosin-based polymer microspheres (RPMs) as stationary phases in HPLC were prepared using methyl acrylic acid as the functional monomer, ethylene glycol maleic rosinate acrylate as the cross-linker, and a carboxylic group as the major functional group. The obtained RPMs were characterized by different analytical techniques. The results indicated that the RPMs have a regular spherical shape with porous surfaces, an average particle size of 5.5 μm, a surface area of 96.73 m2 g−1, and an average pore size of 11.68 nm. Moreover, the RPMs displayed good thermal stability. Theophylline, caffeine, tetrahydropalmatine, and berberine hydrochloride were used as probes to study the separation properties of alkaloids and their analogs on an RPM chromatographic column. Theophylline/caffeine and tetrahydropalmatine/berberine hydrochloride were separated by a rosin-based chromatographic column under optimum chromatographic conditions, and their resolution factors were 5.29 and 3.72, respectively. Furthermore, the chromatographic thermodynamics and separation mechanism were also studied. Thermodynamic data obtained by van’t Hoff plots showed that their separation on the RPM chromatographic column was an enthalpy-driven exothermic process. Microcalorimetry and zeta potential were employed to investigate the separation mechanism of the binding of alkaloids to the rosin-based polymer surface. The RPM and theophylline (or caffeine) interact through hydrogen bonding interactions, whereas the interactions between the RPM and tetrahydropalmatine (or berberine hydrochloride) arose from hydrogen bonding and electrostatic attraction.

Natural resins such as benzoin, propolis and rosin have been widely employed in the pharmaceuticals. In this study, in situ forming gels (ISG) were prepared using natural resins as matrix forming agents to deliver vancomycin hydrochloride (VH) for periodontitis treatment. The formulations were investigated for their physicochemical properties, drug release and antimicrobial activities. Transformation from a solution to a solid matrix was achieved after the formulas were exposed to a simulated crevicular fluid. The rate of resin matrix formation was found to decrease with time and became more opaque owing to gradual phase separation with resin network formation. They flowed with pseudo-plastic behavior and provided appropriate injectability as well as good mechanical properties. Sustained VH release was attained for a 5-day period. VH-loaded natural resin ISGs inhibited against Staphylococcus aureus, Porphyromonas gingivalis, Candida albicans, and Streptococcus mutans. Natural resin-based ISGs comprising of propolis or benzoin showed a more effective delivery of VH than that of rosin. Thus, VH-loaded benzoin and propolis ISGs were found to have a possible application for infected periodontitis treatment.

It is known that the tremendous structural units in a polymer chain can result in a larger free volume of the bulk, which can effectively decrease the dielectric constant of the polymer. According to this design strategy, a novel rosin-based BCB monomer containing Si–O and characterized by a symmetrical molecular structure was successfully synthesized. Subsequently, an amorphous cross-linked network, with a dielectric constant of 2.44 and a dielectric loss of 2.02 × 10−3 at 1.0 MHz, was formed after the monomer was polymerized at an appropriate temperature. Additionally, the effects of the rosin skeleton on other properties of the modified BCB resin were studied. Compared with those of a BCB resin without a rosin skeleton, the dielectric properties, thermal stability, mechanical properties, and hydrophobicity of the rosin-modified BCB resin were significantly improved. The improvement of these properties is due to the presence of a hydrogenated phenanthrene ring in rosin, which is difficult to rotate and hinders the movement of the molecular chains in the modified BCB resin. Meanwhile, the rigidity and hydrophobicity of the hydrogenated phenanthrene ring can also improve the properties of the BCB resin. Thus, this study shows that the introduction of a rosin skeleton can significantly and comprehensively improve the properties of BCB materials.

The aim of this work is to obtain better water resistance properties with additives to starch at the size press. A further goal is to replace petroleum-based additives with environmentally friendly hydrophobic agents obtained by derivatization of wood rosin. A crude wood rosin (CWR) sample was methylated and analyzed with gas chromatography-mass spectrometry (GC-MS). Methyl abietate, dehydroabietic acid, and abietic acid were the main constituents of the sample. The crude wood rosin samples were fortified with fumaric acid and then esterified with pentaerythritol. Fortified and esterified wood rosin samples were dissolved in ethanol and emulsified with cationic starch to make them suitable as hydrophobic additives for surface treatment formulations in mixtures with starch. These hydrophobic agents (2% on a dry weight basis in a cationic starch solution) were applied to paperboard, bleached kraft paper, and test liner paper using a rod coater with a target pickup of 3-5 gsm. The solution pickup was controlled by varying the rod number. The amounts of hydrophobic material applied in the preparation of the paper samples were 32.2, 48.6, and 35.1 lb/ton pickup compared to three types of base papers. Basic surface features of fortified and fortified and esterified rosin-treated paper were compared with base paper and paper treated with starch alone. Lower Cobb(60) values were obtained for fortified and esterified samples than for linerboard samples that had been surface-sized just by starch. Thus, as novel hydrophobic additive agents, derivatives of CWR can be a green way to increase hydrophobicity while reducing starch consumption in papermaking.

Rosin is a sustainable resource, which is mainly composed of resin acid. Rosin-modified resin is widely used in adhesives, inks, coatings, and other fields, and its stability is very important for the production, storage, and use of products. Thermal stability and reactivity of three resin acids (levopimaric acid, neoabietic acid, and dehydroabietic acid) and four rosin-modified resins were studied using an accelerating rate calorimeter (ARC). They are stable, and exothermic reactions do not occur even when they were heated to 200 °C under a nitrogen atmosphere, but they are unstable under an oxygen atmosphere. The mechanism of the oxidation reaction process was found: first, resin acids absorb oxygen, and then an exothermic oxidation occurs. The initial exothermic temperature (T 0) of levopimaric acid, neoabietic acid, and dehydroabietic acid are 354.01, 353.83, and 398.20 K, the initial oxidation kinetics shows a second-order reaction, and the activation energies (E a) are 42.90, 58.05, and 46.60 kJ/mol, respectively. Peroxide concentration of three resin acids were determined by iodometry. The T 0 values of hydrogenated rosin, disproportionated rosin, hydrogenated rosin glyceride, and hydrogenated rosin pentaerythritol ester, the four rosin-modified resin, are 353.71, 348.32, 412.85, and 412.44 K. Levopimaric acid and neoabietic acid have higher oxidative reactivity and easily undergoes an oxidation reaction at lower temperature. Rosin-modified resins are stable and find it difficult to undergo oxidation reactions.

The esterification of rosin with pentaerythritol (PE) was studied, using pressurized CO2 as an intensified additive to high-temperature water (HTW), which formed the various esters with different s...

Polyol esters materials, which have been developed from ethylene glycol, glycerol, pentaerythritol and sorbitol with rosin, were investigated for their formed films and coating properties. Films were dried and characterized for chemical and mechanical resistances. Their films were highly resistant to water, solvents (acetone, toluene and methanol), and acids (10% hydrochloric acid and 20% sulfuric acid) and poorly resistant to alkali (10% sodium hydroxide) as well as adhesion, tensile strength, elongation test, modulus of elasticity, pinhole test and scratching and flexibility tests. Incorporation of ethylene glycol, glycerol, pentaerythritol and sorbitol with rosin was done to achieve good mechanical characteristics and high chemical resistance to these films. The prepared compounds were tested for antibacterial activity against Trametes versicolor and Gloeophyllum trabeum.

To explain the differences found in cytotoxicity, interactions of an optically pure rosin derivative 2-amino-5-dehydroabietyl-1,3,4-thiadiazole (L) and its two copper(II) complexes [CuL4Cl]Cl·2CH2C...

Wood polymer composites (WPCs) were prepared via compression molding technique using wood flour and methacrylic anhydride modified epoxidized soybean oil (MAESO) copolymerized with triallyl maleopimarate (TMPA). Various percentages of TMPA were incorporated into the composite system to compare the properties of the final WPCs. TMPA was synthesized from rosin acid and the chemical structure was characterized by 1H-nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. The interaction between wood flour, MAESO and TMPA were revealed by FTIR and scanning electron microscope (SEM) study. Results demonstrated that TMPA was effective in enhancing the mechanical and thermal properties of the composites. Flame retardancy, biodegradability, chemical resistance, and dimensional stability significantly improved after the incorporation of TMPA into the composites. Wood polymer composites loaded with 30 wt% of TMPA exhibited maximum improvement in properties compared to other systems.

In the current context, the development of bio-based and high-performance materials is one of the main research priorities. This study aims to combine the outstanding properties of cellulose nanofibrils (CNFs) or nanocrystals (CNCs) with those of bio-based poly(lactic acid) (PLA). Three-phase multilayered materials (TMLs) were built up by complexing a dry CNF- or CNC-based film with two PLA sheets, using a heat-pressing process. Before the preparation of the nanocellulosic films, CNFs and CNCs were modified by the adsorption of a rosin-based nanoemulsion. The rosin mixture as a natural compound is of interest because of its low cost, renewability, hydrophobicity, and its antimicrobial and antioxidant properties. After demonstrating the efficiency of the complexing procedure, we investigated the barrier properties of the multilayered materials against both oxygen and water vapor, with highly encouraging results. In fact, the presence of nanocellulose as an inner layer between the two PLA films significantly enhanced the oxygen barrier, with a decrease in oxygen permeability comprised between 84 and 96% and between 44 and 50% for neat nanocelluloses and nanocelluloses with rosins as the inner layer, respectively. On the other hand, the antioxidant properties of the final multilayered materials including rosins were highlighted, with a highly encouraging radical scavenging activity close to 20%. Because of the simplicity and the efficiency of the proposed method, this study paves the way toward the development of hybrid multimaterials that could be highly attractive for food packaging applications.

The rational combination of natural molecules is expected to provide new soft material building blocks. Herein, a rosin-based amino acid surfactant was synthesized using dehydroabietic acid and l-serine as the starting materials (denoted as R-6-Ser). Supramolecular hydrogels were formed when β-cyclodextrin (β-CD) was mixed with R-6-Ser at molar ratios of over 0.5:1 and above certain concentrations. The hydrogels were investigated using rheometry, small-angle X-ray scattering, CD spectroscopy, and cryo-transmission electron microscopy (cryo-TEM). The β-CD associated with the isopropyl benzyl group of the dehydroabietic acid unit in R-6-Ser and formed R-6-Ser@β-CD complexes. The complexes and R-6-Ser self-assembled to form elongated right-handed rigid fibers with a diameter of approximately 7-8 nm, which were responsible for the elasticity of the hydrogels. This work demonstrated the feasibility of preparing supramolecular hydrogels from a diterpenoid-based surfactant and β-CD and provides a new means of utilizing the secretions of pine trees.

A novel pH-responsive wormlike micellar viscoelastic solution was constructed by a rosin-based anionic surfactant (Na-MPA-AZO-Na) in the presence of cetyltrimethylammonium bromide (CTAB). The viscoelasticity, aggregate morphology, and pH-responsiveness of the pH-responsive wormlike micelles have been investigated through the method of rheology and cryogenic-transmission electron microscopy. Its corresponding mechanism has been studied using

In this study, the synthesis, characterization, and properties of a short oil length chain–stopped(rapid) alkyd resin is investigated. Gum rosin modified alkyd resin (RA-GR) was prepared using soybean oil, phthalic anhydride, glycerin and gum rosin acid. An alkyd modified with benzoic acid (RA-BA) was also prepared for comparison. FTIR analyses and GPC measurements of the alkyds were used for characterization. Other properties such as the viscosity, acid value, and solid content of the final resins were determined. Separately, the synthesized resins were used in paint formulations without any changes in other parameters such as filler, airdrying agents, solvents, etc. Paints were applied to metal and glass surfaces and the effect of gum rosin was investigated by looking at touch and hard drying times, adhesion to metals and gloss changes. Compared to the benzoic acid modified resin (RA-BA), gum rosin modified resin (RA-GR) exhibited remarkable positive effects on the paint with a better adhesion to the metals, and short drying times without any loses in the glosses.

UV absorption coating is an important function material, which can protect the substrates from photoaging. In this work, a class of sustainable UV-absorbent copolymers derived from ethyl cellulose (EC), fatty acid and rosin were prepared by a combination of atom transfer radical polymerization (ATRP) and click chemistry. To fulfill this strategy, the pendant azides were first attached onto the backbone of EC. Then, ATRP was applied to fabricate well-defined poly(lauryl methacrylate) (PLMA) bearing terminal alkynes. Finally, click chemistry between the pendant azides in EC and the alkynes in PLMA as well as in rosin esters (DAPE), was performed to achieve the cellulose-rosin graft copolymers (EC-(g-DAPE)-g-PLMA) with UV absorption property. The chemical structure of cellulose-rosin graft copolymers was confirmed by FTIR, 1H NMR and GPC. Thermodynamic performance analysis indicated that these EC-rosin graft copolymers showed better thermal stability than EC. Due to the synergistic hydrophobic interaction of rosin and the hydrophobic lauryl groups in PLMA, these graft copolymers showed excellent hydrophobic property, and the static contact angles were all above 90°. In addition, all the EC-rosin graft copolymers showed outstanding and stable UV absorption capability, and maintained excellent UV absorption capability after continuous UV-irradiation for 1 h or being heated to 100 °C for 0.5 h, which had potential application in UV absorption materials.

Abietic acid is one of the main compositions of rosin and tall oil, it has a tricyclic molecular structure, which could be further modified into a branched saturated bicyclic substance with the process of hydro-creaking treatment. Branched decalin and its derivatives are main creaking products from abietic acid, which are promising aviation fuel components since they owe high density, good thermal stability, and low freezing point. In this work, two routes for the target aviation fuel production with abietic acid as raw material were investigated, and their reaction conditions were optimized. Under the optimal conditions, target aviation fuel with a yield of 45.8% saturated bicyclic products was obtained through the route of hydrogenation-cracking process. Meanwhile, a yield of 42.2% was obtained with the route of cracking-hydrogenation process. The branched saturated bicyclic compounds obtained from both processes had excellent fuel properties. Especially, the pour point of the fuel was below −75 °C, which makes the product could be potentially used as bio-aviation fuel in special areas, or as additive to improve low temperature performance of conventional bio-jet fuels. The investigation of this paper provided an efficient and green way for the bio-refinery of rosin or tall oil.

A database of historic paper properties was developed using 729 samples of European origin (1350–1990), analysed for acidity, degree or polymerisation (DP), molecular weight of cellulose, grammage, tensile strength, as well as contents of ash, aluminium, carbonyl groups, rosin, protein, lignin and fibre furnish. Using Spearman’s rank correlation coefficient and principal component analysis, the data were examined with respect to methods of manufacture, as well as chemical stability of paper. Novel patterns emerged related to loss of DP and accumulation of carbonyl groups and acidity with time and the role of lignin and rosin, as well as rate of degradation (k = 10−5 year−1) at room conditions. In-depth understanding of long-term degradation of lignin and rosin is needed to better understand the relationships between composition and degradation of historic paper. This study highlights the importance of mining significant volumes of analytical data, and its variability, obtained from real historic objects.

High-intensity ultrasound (HIUS) energy performance was evaluated using different probe diameters (10 and 20 mm) and specific energies (0.5, 1.0, 3.0, and 5.0 kJ/g) to recover rosavin and rosin from Rhodiola rosea roots. Also, intensified HIUS process conditions (5, 10, 15, and 20 kJ/g) assisted by a cold bath were studied. HIUS energy performance depended on probe diameter at the same nominal power. The larger diameter probe was more energy-efficient, however, the smaller diameter had more ultrasonic intensity (W/cm2). The diameters evaluated did not influence the extraction yields, however, the increase of the HIUS specific energy from 0.5 to 5.0 kJ/g increased phenolic compounds content, antioxidant activities, and rosavin and rosin yields. The HIUS process intensification confirmed that the main extraction mechanism was diffusion and the role of the ultrasound was to increase the diffusion coefficients by increasing the turbulence in the liquid medium due to acoustic cavitation.

The search for renewable fuels or components which may improve or replace fossil fuels is an important step towards a sustainable future. In particular, the pine oleoresin produced by conifer trees, which is composed by turpentine oil and non-volatile rosin, may be transformed into alternative fuels. In this work, combustion of six molecules which can be obtained from oleoresin either by distillation (i.e., α- and β-pinene) or by further oxyfunctionalization (nopol, terpineol, myrtenol, and borneol) was studied to assess the potential of pine oleoresin as raw material for biofuels. Emission indices of the main pollutants (carbon monoxide-CO, unburned hydrocarbons-UHC, and nitrogen oxides-NOx) were obtained in non-premixed co-flow laminar flames of the oleoresin-derived molecules blended with n-heptane. The main characteristics of the flames (i.e., temperature and height) were also determined. Significant increase in flame temperature and reduction in CO and UHC emissions with respect to n-heptane were observed with nopol, terpineol, and myrtenol, along an increase in NOx emissions, suggesting an improvement in combustion performance. In addition, differences in emission indices, evidenced for these molecules (even between α- and β-pinene), suggest the importance of the molecular structure in the combustion reaction.

Conversion of rosin to its pentaerythritol ester provides a means of improving its water resistance, alkali resistance, and oxidation resistance, thereby increasing its stability. Rosin pentaerythritol ester is much more amenable to industrial applications than the parent compound. To overcome the difficulty of catalyst recovery and its associated high cost during the synthesis of rosin pentaerythritol ester, Fe3O4-supported ZnO catalysts, such as Fe3O4@ZnO and Fe3O4@SiO2–ZnO, have been designed and synthesized. The structures, morphologies, and compositions of the materials have been characterized by TEM, XRD, and XPS. The results of esterification reactions demonstrate that Fe3O4@SiO2–ZnO has excellent catalytic performance and stability. The degree of esterification in the production of rosin pentaerythritol ester reached 87.9%, far exceeding the yields attained with other catalysts. Moreover, the catalyst could be reused five times without incurring a loss of activity. The effects of zinc source, zinc loading, and reaction conditions on the esterification have been investigated in detail. This study provides a class of heterogeneous catalysts with excellent properties for the synthesis of rosin pentaerythritol ester. In our paper, the optimum process conditions for obtaining rosin pentaerythritol ester have been identified as zinc nitrate as the zinc source, a theoretical loading of zinc source of 0.45 g, a reaction temperature of 250 °C, a reaction time of 5 h, and a catalyst loading of 0.2 g, when starting from rosin (15 g) and pentaerythritol (1.7 g). The conversion rate was 87.9%, and the acid value was 25.0 mg KOH g−1. This research provides an improved protocol for the rosin esterification reaction.

To protect pore structures of metal foam in the machining process, a new milling method was proposed that different filling materials were used for solidification of pore structure. In this way, the milling process was performed using the copper foams with three different types of filling materials (paraffin, rosin, and mixture of hydrogenated rosin and sodium stearate with a mass ratio of 4:1). During milling process of copper foam, the cutting forces and cutting temperatures were measured and analyzed. The surface morphology of copper foam was observed according to the SEM results. Moreover, the conformal rate, which was considered an index to estimate the quality of milling process, was calculated using pore size statistics. Our results show that with the increased spindle speed and feed rate, the conformal rate of pore structure was firstly increased and then decreased. With the increase of feed rate, the cutting temperature was slightly decreased. When the spindle speed was increased, the cutting temperature was increased, while the highest cutting temperature was much lower than the melting temperature of the filling materials. Better conformal performance and high conformal rate were obtained with the hydrogenated rosin and sodium stearate at a ratio of 4:1, at a spindle speed of 300 r/min and a feed rate of 160 mm/min. When the optimized processing parameters were adapted to milling the copper foam with filling material, the conformal rate can reach 96.4%. Correspondingly, the highest cutting temperature and the maximum cutting force perpendicular to the feeding direction and along the feeding direction were 37.4 °C, 44.91 N, and 24.60 N, respectively.

Plant derived bio-based materials are environmental-friendly and provide a cheap and an attractive source for synthesis of controlled release urea fertilizers which have positive impact on plants’ ...

Present work focused on synthesis of green hydrogel polymer of gum rosin alcohol/psyllium crosslinked poly (acrylic acid) [(GrA-Psy)-cl-PAA] under vacuum condition. Use of both psyllium and gum rosin alcohols as backbones could lessen the burden on the environment, as more natural aspect is drawn in the hydrogel polymer. The various reaction parameters for the synthesis of hydrogel polymer were systematically optimized as a function of percentage swelling. The optimized ecofriendly hydrogel polymer was characterized using XRD, FTIR, FE-SEM and TGA techniques, which supported the successful formation of crosslinked three-dimensional network structures. (GrA-Psy)-cl-PAA was further studied as an adsorbent for the removal of methylene blue dye from an aqueous solution. Adsorption parameters such as the amount of adsorbent and pH were optimized to obtain the maximum percentage of dye removal. Kinetics of the adsorption process was analyzed using pseudo-first-order, pseudo-second-order and Elovich kinetic models. Adsorption kinetics followed pseudo-second-order model (non-linear) for all the concentrations studied. Non-linear forms of Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich isotherm models were studied for the adsorption process and it was observed that it goes well with both Langmuir and Freundlich isotherms. Thermodynamic parameters were also evaluated which indicated that the adsorption process was exothermic and spontaneous. Furthermore, the candidate polymer retained a reusability tendency for two consecutive cycles of adsorption/desorption. Thus, the synthesized novel material was taken as a potential to act as green adsorbent in treatment of industrial wastewater.

A nonionic surfactant based on chitosan and rosin, i.e. dehydroabietyl glycidyl ether grafted hydroxypropyl chitosan (DAGE-g-HPCS), was synthesized for the first time through reaction between hydroxypropyl chitosan (HPCS) and dehydroabietyl glycidyl ether (DAGE). The surface activities of DAGE-g-HPCS in aqueous solution were investigated via determination of surface tension, and its emulsifying ability was evaluated according to the stability time of emulsion composed of benzene-water with DAGE-g-HPCS as emulsifier; the foam stability was evaluated using the oscillation method. Through modulating the molecular weight of HPCS and the grafting degree (DG) of DAGE-g-HPCS, the emulsion stability and foam stability were surprisingly controllable. Compared to HPCS and specific emulsifier, the stability time of emulsion composed of benzene-water with DAGE-g-HPCS showed a remarkable performance with DG of 16.5% as the emulsifier was 7320 s, and the foam retention of DAGE-g-HPCS with 2.0 g·L-1 was 91.5%. Simultaneously, the critical micelle concentration (CMC) of DAGE-g-HPCS decreased with increased DG, while the emulsifying ability and foam stability exhibited opposite trend. The CMC, emulsifying ability, and foam stability of DAGE-g-HPCS increased with decreased HPCS molecular weight. These results demonstrated that the DAGE-g-HPCS was an excellent surfactant that should be considered as a promising substitute for petrochemical nonionic surfactant.

Rosin and cellulose nanocrystals (CNCs) are easily extracted from agricultural pines/conifers and natural cellulose, and poly(3-hydroxybutyrate- co-3-hydroxyvalerate) (PHBV) are extracted from agri...

The aim of this study is to estimate antifouling and anticorrosion potential of organic extracts from Pseudoalteromonas piscicida 2202. Field tests of rosin-based experimental paint indicate that butanol extract of P. piscicida 2202 effectively prevents biofouling for 3 months. A protective film forms at the metal/solution interface in the presence of butanol extract, which leads to a decrease in the mild steel corrosion rate. The EIS method has shown that the incorporation of butanol extract in rosin-based paints improves the barrier properties of the coating by reducing the water uptake.

A self-designed mini gas–solid reaction device was applied as promising equipment to investigate the oxidation characteristics and kinetics of the glycerol ester of rosin (GER) under 254 nm UV irradiation in air. Peroxide formation during the photo-oxidation process was analyzed by iodimetry. The peroxide concentration is related to the light intensity (I) and the temperature (T), and increasing I and T would destabilize the GER by accelerating peroxide generation. The photo-oxidation of GER followed pseudo-first-order reaction kinetics under a given hypothesis. A linear relationship was observed between activation energy and the logarithm of light intensity (ln I), which can be expressed as Ea = −3.575 ln I + 34.943 under the experimental conditions. This research indicated that under 254 nm UV irradiation GER could be easily oxidized even at room temperature.

[EN] The present study aims to investigate the effects of gum rosin (GR) microspheres coating over the hydrophobicity of the outer layer of a polypropylene (PP) based surgical face mask. The gum rosin coating was deposited over the surface of the face mask outer layer by electrospraying technique. The deposition of GR microspheres was confirmed by field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR) analysis. The thermal analysis determined a cooperative effect between the microspheres and the mask fibre to increase the maximum degradation rate temperature and the onset degradation temperature. To follow the effect of the GR microspheres coating over the hydrophobicity of the surgical face mask, FESEM and wettability analyses were conducted before and after 3, 6, and 9 h of wearing time. In the FESEM image, it was seen that the microsphere was homogeneously distributed over the nonwoven fibre and its presence increases the roughness of the fibres due to the bulge of microspheres. The wettability measurements suggest that the microspheres coating helps to keep the original hydrophobicity of the outer layer of the surgical face mask even after 6 h of wearing time. Indeed, after 9 h of wearing time, the water contact angle (WCA) of the GR coated face mask is higher than the WCA of the surgical face mask without the coating at 3 h of wearing time. Therefore, the gun rosin microspheres coating improved the hydrophobicity of the surgical face mask which may allow improved protection and/or extended lifetime of use., This research was funded by the Spanish Ministry of Economy and Competitiveness (MINECO), project: PROMADEPCOL (MAT2017-84909-C2-2-R). Cristina Pavon thanks Santiago Grisolía fellowship (GRISOLIAP/2019/113) from Generalitat Valenciana. Miguel Aldas thanks Secretaria de Educación Superior, Ciencia, Tecnología e Innovación (SENESCYT, Ecuador) and Escuela Politécnica Nacional.

The morphology and physicochemical properties of ordered molecular aggregates are closely related to surfactant molecules. Herein, a rosin-based amine oxide surfactant containing a large hydrophobic group (abbreviated R-10-AO) was synthesized from dehydroabietic acid, which is an important derivative of rosin. Cryogenic transmission electron microscopy (cryo-TEM) images and small-angle X-ray scattering (SAXS) showed that at a concentration of ∼5 mM, R-10-AO molecules formed flexible nanobelts with a thickness of only 2–3 nm. The width of these nanobelts was 50–150 nm and the length was more than 1 μm. The formation of the stable nanobelts arose from the strong van der Waals forces of the bulky hydrophobic portions of R-10-AO in solution, facilitating the stability of the asymmetrical aggregates. Rheological tests showed that the formed nanobelts were thermodynamically stable. The entanglement of these nanobelts led to significant viscoelasticity of the solutions. The zero-shear viscosity (η0) of the R-10-AO solution reached 10 Pa s at a concentration of 5 mM, which is much greater than that of most wormlike micellar solutions. This work provides the inspirations of preparing aggregates with novel properties using natural products.

The vaping liquid additive vitamin E acetate (VEA) was strongly linked to the 2019 United States nationwide outbreak of pulmonary lung illness (EVALI) associated with e-cigarettes or vaping liquids. Our laboratory received over 1,000 vaping liquid products for identification of the vaping liquid additives, including hundreds of vaping products from EVALI patients. In this work, we present results obtained for the GC-MS identification of numerous vaping liquid additives in a large subset of ca. 300 Cannabis vaping liquids, including vitamin E acetate, medium chain triglycerides oil (MCT oil), polyethylene glycols, squalane, triethyl citrate, dipropylene glycol dibenzoate (DPG dibenzoate), pine rosin acids, pine rosin methyl esters, and sucrose acetate isobutyrate (SAIB). Confirmation of DPG dibenzoate and SAIB using LC-HRMS is also presented. GC-MS analysis for additives identified as the parent compounds was conducted after separation on a commercial 5% phenyl phase. GC-MS analysis for additives identified as the trimethylsilyl derivatives was conducted after separation on a commercial 35% silphenylene phase. LC-HRMS analysis was conducted using gradient elution with either C18 or phenyl-hexyl phases and determination of exact masses for the target compounds. In addition to providing rapid methods for the identification of vaping liquid additives, this work highlights the variety of Cannabis vaping liquid additives in current use.

Rosin is an abundant natural product. In this paper, for the first time, a rosin derivative is employed as a monomer for the preparation of polyurethane vitrimers with improved properties. A novel rosin-based polyurethane vitrimers network was constructed by the reaction between isocyanates (HDI) as curing agent and monomers with alcohol groups modified from rosin. The dynamic rosin-based polyurethane vitrimers were characterized by FTIR and dynamic mechanical analysis. The obtained rosin-based polyurethane vitrimers possessed superior mechanical properties. Due to the dynamic urethane linkages, the network topologies of rosin-based polyurethane vitrimers could be altered, contributing self-healing and reprocessing abilities. Besides, we investigated the effects of healing time and temperature on the self-healing performance. Moreover, through a hot press, pulverized samples of 70%VPUOH could be reshaped several times, and the mechanical properties of the recycled samples were restored, with tensile strength being even higher than the of that of the original samples.

Supramolecular hydrogels have attracted great attention due to their special properties. In this research, bio-based supramolecular hydrogels were conveniently constructed by heating and ultrasounding two components of dehydroabietic acid with a rigid tricyclic hydrophenanthrene skeleton and morpholine. The microstructures and properties of hydrogels were investigated by DSC, rheology, SAXS, CD spectroscopy, and cryo-TEM, respectively. The critical gel concentration (CGC) of the hydrogel was 0.3 mol·L−1 and the gel temperature was 115 °C. In addition, the hydrogel showed good stability and mechanical properties according to rheology results. Cryo-TEM images reveal that the microstructure of hydrogel is fibrous meshes, its corresponding mechanism has been studied using FT-IR spectra. Additionally, oil-in-water gel emulsions were prepared by the hydrogel at a concentration above its CGC, and the oil mass fraction of the oil-in-water gel emulsions could be freely adjusted between 5% and 70%. This work provides a convenient way to prepare bio-based supramolecular hydrogels and provides a new method for the application of rosin.

Several well-preserved polychrome lacquered coffins were found in Zhang Dong family’s tombs in Shaanxi, China, rare in the history of archaeological excavation. In the lacquered coffins, a large amount of dark solid of suspected natural resin was unearthed with mysterious compositions and uses, exerting a tremendous fascination on archaeologists. In this work, a new method was explored for the identification of the suspected natural resin, mainly based on thermogravimetry (TG), elemental analysis (EA), scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) and Fourier transform infrared spectrometry (FT-IR). The results suggested that the sample was mainly composed of organics with a content of 81.66% and little inorganics with a content of 2.21% by water excluded. Rosin with the main component of abietic acid (molecular formula C20H30O2) was identified as the principal component of the sample. Dehydrogenated abietic acid (DHA) and other oxides were also tested out. FT-IR confirmed the identification results. SEM revealed the rough surfaces evenly covered with holes of similar sizes. The use of this method directly obtained integral quasi-molecular ion fragments and molecular components of the sample. As a result, intricate multi-stage mass spectrometry is avoidable, which dramatically simplifies the analysis procedure. This approach is simple and effective for the identification of precious relic samples, requires no references, and has potential for the analysis of these kinds of unknown samples. Especially, for the first time, EA is used to identify natural resins from archaeological sites.

The poor mechanical properties and disadvantages of catalysts limit the application of self-healing materials. To address these issues, catalyst-free self-healing bio-based polymers (AESO-EMPA polymers) with robust mechanical properties were prepared using epoxidized maleopimaric anhydride (EMPA) and aminated epoxidized soybean oil (AESO). The AESO-EMPA polymers are recyclable and exhibit self-healing and shape memory because of the dual-dynamic network of multiple H-bonds and dynamic ester bonds in the structure. Under the synergistic catalysis of the tertiary amines and hydroxyl groups originated from the polymers, the polymers in this study achieve network rearrangement without the need for additional catalysts. The polymers also exhibit excellent mechanical properties with a tensile strength of 29.1 ± 0.25 MPa and a Tg of 80.2 °C owing to the unique rigid backbone of rosin and the dual-dynamic network. The AESO-EMPA polymers can be used as reusable adhesives and exhibit excellent shear strength and repair rates.

Preparation and application of sustainable polymers derived from renewable resources are of great significance. The aim of this study is to synthesize a kind of sustainable polymeric micelles from rosin and vegetable oils via atom transfer radical polymerization (ATRP) and to investigate the doxorubicin delivery properties of these micelles. Dehydroabietic acid–based poly lauryl methacrylate (DA-PLMA) with narrow PDI of 1.13 was prepared in a well-controlled process using rosin as an ATRP initiator. Thereafter, carboxylic groups were introduced to form poly methacrylic acid (PMAA) moieties in DA-PLMA polymer via acid hydrolysis. The resulted DA-PLMA-PMAA could self-assemble in water to form pH-dependent polymeric micelles with a diameter of ∼65 nm and PDI as low as 0.105. Owing to the existence of rosin, DA-PLMA-PMAA micelles also showed self-fluorescence properties. In addition, Dox-loaded micelles were prepared in aqueous solution with the drug-loading capacity as high as 16.0% and showed sustained-release characteristics. These results demonstrate great promise for designing polymeric micellar from rosin and vegetable oils.

The current investigation presents a green mechanochemical procedure for the synthesis of a special kind of rubber-compatible organo-montmorillonite (OMMT) for use in the inner liner compound of tires. The compatibility character of the OMMT arises from the mechanochemical reaction of the raw bentonite mineral and gum rosin as some of the organic constituents of the inner liner composition. The monitoring of OMMT synthesis by various characterization techniques reveals that gum rosin gradually intercalates into the montmorillonite (MMT) galleries during milling and increases the interlayer spacing to 41.1 ± 0.5 Å. The findings confirm the simultaneous formation of single- or few-layered OMMT platelets with average sizes from the sub-micron range up to several micrometers during the milling process. The mechanical properties of the OMMT/rubber nanocomposite, such as tensile strength, tear resistance and elongation, present a good enhancement in comparison to the un-modified material. Moreover, the organo-modification of the inner liner composition also leads to a property improvement of about 50%.

This work deals with the synthesis of biodegradable and UV resistant wood polymer composites (WPCs) via compression moulding technique. As outdoor applications become more widespread, durability be...