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Pressure-sensitive adhesives (PSAs) made from norbornene-functionalized terpenoid-based monomers are reported as a possible alternative to the conventional petrochemically based PSAs. For this, tetrahydrogeranyl, menthyl, and isobornyl norbornenate monomers, with a renewable carbon content up to 72%, are synthesized and copolymerized via ring-opening metathesis polymerization (ROMP) with cyclooctadiene and 5-norbornene-2-carboxylic acid. ROMP enables a much faster and controlled polymerization process in comparison to free radical polymerization techniques when targeting high molecular weights and therefore unlocks a potential to design a unique class of PSA materials. The moduli at bonding and debonding frequencies of the obtained PSAs are plotted in the Chang classification system and are used to predict their adhesive performance. Tack and peel measurements indicate that the terpenoid-based norbornenate formulations show similar adhesive properties in comparison to the previously investigated acrylic counterparts.

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

Purpose This study aims to prepare low-cost biomaterials from renewable natural resources (rosin). Design/methodology/approach Preparation of different biomaterials, ethylene glycol maleic rosin (EGMR), glycerol maleic rosin, pentaerythritol maleic rosin and sorbitol maleic rosin (SMR) esters, then evaluated by stability studies, moisture absorption, swelling index parameters, thermogravimetric analysis and skin irritation studies. Findings The prepared rosin derivatives had excellent moisture safety, according to the results. From EGMR to SMR, the swelling indices increase. Research limitations/implications These rosin biomaterials were used in coating, especially in the field of pharmaceutical coating, and good results were obtained in this study. Practical implications As these biomaterials rosin derivatives have excellent moisture resistance, they are recommended for use as coating materials for moisture-sensitive drugs. Originality/value There has recently been a lot of interest in researching the effects of rosin derivatives in various drug delivery systems.

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.

Rosin is renewable biomass with the potential to enhance wood properties. However, its high leaching rate restricts the durability of rosin impregnation. To immobilize rosin in wood structure, poly...

Pyrolysis behavior of resins is essential for their high-temperature application. Herein, the high-temperature stability and pyrolysis kinetics and mechanism of rosin glyceride (RGE), hydrogenated ...

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.

Purpose This study aims to provide control of liquids, especially against water-based ink on the paper and paperboard surface with natural substances, in also practical and greenway. Design/methodology/approach The paper surface was treated with natural rosin and its derivatives to obtain a hydrophobic effect and to improve printing properties. The oleoresin samples collected from Pinus nigra Arnold and Pinus pinaster Aiton trees in the controlled area and turpentine content removed was by hydrodistillation. The gum rosin (GR), fortified 10% with maleic anhydride (MGR) and esterified with 10% pentaerythritol (PMGR) samples solved in a simply alcohol and sprayed the base paper surface directly with a spray gun. Base paper samples were paperboard, bleached paper and test liner paper. Then, flexo printing was applied and printability properties were measured. Findings The treatment weights of these paper samples were 1.8 ± 0.5, 1.3 ± 0.5 and 0.7 ± 0.2 g/m2, respectively, compared to the base paper. Greater Cobb60 results were obtained from modified rosin samples than unmodified gum rosin-sized paperboards and the PMGR surface treatment reduces Cobb60 values by 20% and MGR treatment reduces 15% comparing to the base sheet. Then, the printing procedure was applied to the surface of the treated materials using a flexo printing system. As a result of the treatment better print density, chroma and print lightness value consumed a less hydrophobic agent and controlling water-based flexo ink on the base paper surface. Originality/value The unique aspect of this work was improving the hydrophobicity of the paper surfaces was achieved by spraying with natural rosin and derivatives.

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.

Localized delivery systems have been typically designed to enhance drug concentration at a target site and minimize systemic drug toxicity. A rosin/cinnamon oil (CO) in situ forming gel (ISG) was developed for the sustainable delivery of imatinib mesylate (IM) against colorectal cancer cells. CO has been claimed to express a potent anticancer effect against various cancer cells, as well as a synergistic effect with IM on colorectal cancer cells; however, poor aqueous solubility limits its application. The effect of rosin with the adding CO was assessed on physicochemical properties and in vitro drug release from developed IM-loaded rosin/CO-based ISG. Moreover, in vitro cytotoxicity tests were conducted against two colorectal cancer cells. All formulations exhibited Newtonian flow behavior with viscosity less than 266.9 cP with easier injectability. The adding of CO decreased the hardness and increased the adhesive force of the obtained rosin gel. The gel formation increased over time under microscopic observation. CO-added ISG had a particle-like gel appearance, and it promoted a higher release of IM over a period of 28 days. All tested ISG formulations revealed cytotoxicity against HCT-116 and HT-29 cell lines at different incubation times. Thus, CO-loaded rosin-based ISG can act as a potentially sustainable IM delivery system for chemotherapy against colorectal cancer cells.

A series of tung oil-rosin-based polyester (TRP) used as internal sizing agents were prepared using rosin, tung oil, maleic anhydride, and glycerol. TRP structure and properties were examined using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC). The TRP latexes were subsequently used as internal sizing agents, and the sizing properties were evaluated using a scanning electron microscope (SEM), a video-based dynamic contact angle measuring device and a Cobb absorbency tester. The optimal conditions for preparing the TRP sizing agent were as follows: the hydroxy-carboxyl ratio of the material was 0.25; the maleic anhydride dosage was 20 % of rosin; and the tung oil dosage was 40 % of rosin. Under the best conditions, the sized paper Cobb-60 was 15.6 g / m 2 \text{g}/{\text{m}^{2}} , the tensile index was 45.1 N·m/g, the burst index was 3.1 kPa· m 2 {\text{m}^{2}} /g, and the tear index was 15.6 mN· m 2 {\text{m}^{2}} /g.

Natural chemicals obtained from the renewable resources were widely used in the modification of plant fibers. In this report, in order to develop thermoplasticity of materials, the bamboo powder (BP) after hydrothermal pretreatment (BP-LHW) was efficiently modified with natural rosin acid (BP-LHW-RA) by esterification reaction under heterogeneous condition. The results indicate that the modified BP-LHW-RA presents a strong peak at 1743 cm−1 in the FT-IR spectra, which attributed to the –C = O vibration of the ester group formed by the reaction between rosin acid and the BP-LHW, confirming that BP-LHW was successfully grafted with rosin acid. The C1/C3 ratio of BP-LHW-RA increased 1.35 times as compared with BP-LHW in XPS analysis. Meanwhile, the crystallization index of BP-LHW-RA decreased by 4.62%, and its surface became smooth and full. Moreover, the glass transition temperature of BP-LHW-RA was 200 °C. The work presents a green and feasible route to prepare bio-based materials with desired thermoplasticity by grafting natural rosin onto biomass substrate. The bio-based material with desired thermoplasticity was prepared by grafting natural rosin onto bamboo powder.

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 effectiveness of Air entraining agent (AEA) in concrete under low air pressure in the plateau area decreased. A type of new AEA, named MRE was synthesized to increase bubbles` stability in fresh concrete under low air pressure. The performance of MRE solution and concrete with MRE were tested under 60 kPa and 100 kPa compared with commercially gemini AEA (DCC). The test results showed that the foam volume of MRE and DCC solution under 60 kPa was reduced by 3% and 9% than under 100 kPa. The bubble liquid film strength of MRE is 63% higher than that of DCC. For concrete with MRE and DCC under 60 kPa, the air content was 2% and 16% lower, the relative dynamic modulus of concrete reduced by 6% and 15%, and the bubble spacing factor under 60 kPa increased by 17% and 39% respectively compared with that under 100 kPa. MRE can increase the freeze-thaw resistance of concrete under low air pressure without affecting concrete strength and is suitable for high altitude concrete.

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.

Solvent-based polychloroprene (CR) adhesive was formulated using four different types of tackifiers. Wood rosin (WD), coumarone-indene resin (CI), terpene-phenolic resin (TP) and para-tert-butyl ph...

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 possibilities of regulation of the physicomechanical properties of construction materials based on diatomite by changing the recipe and technological parameters of their synthesis are studied. It is proposed to use a modifying additive, change conventional glass formers by an alkaline solution of rosin or foaming agents based on resinous plant raw materials, and simplify standard technologies of obtaining diatomite materials. The materials having a wide range of characteristics are obtained; namely, materials with density from 0.6 to 1.07 g/cm3 and strength from 2 to 18 MPa are obtained by semidry pressing, and materials with density from 0.32 to 0.63 g/cm3 and compressive strength from 0.6 to 4.5 MPa are obtained by the foaming method and the method of combustible additives.

The antimicrobial activity of resin acid derivatives was studied. The highest inhibitory activity Escherichia coli and Bacillus subtilis was found to be characteristic of isomerized rosin and 12-bromodehydroabietic acid, as well as their potassium salts. Potassium 12-sulfodehydroabietate only slightly inhibits growth of Candida tropicalis cells. PASS online calculation showed that all of the resin acids derivatives and their potassium salts have high mucosal (Pa 93‒98%) and pronounced antiviral (influenza) protective activities (Pa 70‒80%).

With the development of rubber technology the requirements for rubber products are becoming more and more strict. Enhancing the interfacial bonding strength between vulcanized natural rubber (NR) a...

Fruit coating is an effective method in the post-harvest industry to replace the natural wax that is removed during cleaning and processing. Recently, there has been a growing interest in using natural edible coatings instead of non-prescription synthetic waxes for human health and the environment. Today consumers prefer natural products to synthetic ones. Therefore, natural fruit coatings are developed from natural ingredients (Sherak, rosin, gum Arabic, sugar industry water, ethanol) without the use of ammonia or morpholine as an alternative to synthetic coatings. Many studies have shown that fruit coatings significantly slow down changes in weight, hardness, ascorbic acid, and overall physiological loss of sensory quality during storage compared to uncoated fruits. On the other hand, this has led to a positive method, showing small variations in total soluble solids and fruit. Acidity was recorded for all treatments. Furthermore, the difference between natural and synthetic fruit coatings was not important. Therefore, natural fruit coatings are assumed to be a great alternative to synthetic fruit coatings.

Disposal of fallen leaves in city area has become serious issue because of increasing amount of the fallen leaves and of decreasing handling amount of daily waste incinerating facility or landfill. In order to increase the usability of fallen leaves, the sheet-like composite was prepared through pretreatment processes and manufacturing processes of fallen leaves. The crushed fallen leaves were fractionated by using 10 mesh and 40 mesh screen, which could divided the stem and the lamina because the lamina of the fallen leaves was more breakable than the stem. The effects of fallen leaves particles size on the properties of the sheet-like composite were evaluated. The fraction between 10~40 mesh of the crushed fallen leaves resulted in the higher strength properties of the composite than that of the larger size particles or the smaller size particles. The bulkier structure of the composite made of 10 mesh fraction showed higher water resistance property and lower water holding capacity. The density and the strength property of the composite was controlled by addition of red clay as filler. The surface treatment with rosin resulted in the higher water resistance and the neutralization of alkali pH.

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.

In situ forming matrix (ISM) is an injectable drug delivery system containing a drug-loaded polymeric solution. It was applied for local drug administration such as into a periodontal pocket for periodontitis treatment with an antimicrobial agent. ISM can transform with phase inversion into the solid-like matrix after contact an aqueous environment by solvent exchange mechanism. This study aims to develop ISM which various concentrations of rosin (R) as matrix former dissolved in organic biocompatible and biodegradable solvents such as N-methyl-2-pyrrolidone, dimethyl sulfoxide and 2-pyrrolidone. Physicochemical characterization and matrix formation behavior owing to phase inversion of R ISM were evaluated including pH, density, viscosity, contact angles, surface tension, expelling force through a syringe, matrix formation behavior and morphological change. The density of all R ISM exhibited in the range of 1.03-1.11 g/cm3 and contact angles (9.04-44.13°) indicated a good wetting property. Higher R concentration decreased pH of ISM owing to increased amount of abietic and pimaric acid from R while the viscosity, contact angles and force for expelling a syringe were increased. The viscosity of R ISM in dimethyl sulfoxide was less than that in 2-pyrrolidone; thus, ISM using dimethyl sulfoxide as a solvent exhibited good injectability. ISM comprising R concentration > 30%w/w promoted a faster matrix growth in which the amount of occurred R matrix was enhanced with time and the rate of matrix formation was lower with time. Doxycycline Hyclate (Dx)-loaded 40%w/w ISM in dimethyl sulfoxide (Dx-DR) had pH of 3.70, density of 1.1084 ± 0.0005 g/ml, viscosity of 35.72 ± 0.00 cPs, contact angles of 26.87 ± 2.40°, surface tension of 37.11 ± 0.11 mN/m and expelling force of 23.98 ± 0.18 N. It showed the sustainable Dx release in simulated crevicular fluid and the efficient antimicrobial activity against Staphylococcus aureus and Porphyromonas gingivalis. Thus, this phase inversion induced R ISM using dimethyl sulfoxide as a solvent showed potential as an antimicrobial agent-loaded drug delivery system for periodontitis treatment.

The aim of this study was to investigate the effect of gum rosin impregnation upon a low quality young teak wood in order to enhance its quality. The main objective of the treatment was to enhance the dimensional stability, as well as strength and to reduce the hygroscopicity. A 15-years old thinned teak wood (Tectona grandis L.f.) and gum rosin from Pinus merkusii Jungh. et de Vries were used for wood modification treatment by impregnation. Three kinds of non-polar solvents, i.e. turpentine oil, petroleum oil and n-hexane-, were used to make gum rosin solution. The results indicated that gum rosin impregnation did not markedly enhance the quality of young teak wood in terms of either dimensional stability or hygroscopicity; however, a little enhancement was delivered by using 15% gum rosin solution with n-hexane as the solvent. The treatment with petroleum oil solvent (at concentration of 7.5%) and at 15% concentration with n-hexane solvent resulted in highest bending properties. The highest bonding strength in dry condition was resulted by treatment with turpentine oil solvent.

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.

Gelatin-rosin gum complex nanoparticles (GGRNPs) have been synthesized by complex coacervation method. The particles were extensively characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and particle size analysis based on dynamic light scattering (DLS). The GGRNP3 were stable and their average particle size was ~ 153 nm. GGRNPs were evaluated as the carrier matrix for 5-fluoro uracil (5-FU), and the release behavior of 5-FU was examined by swelling and in vitro dissolution tests in simulated gastrointestinal fluid (SGF) for first 2 h followed by 14 h in simulated intestinal fluid (SIF). About 71% drug release was witnessed (SGF = 21%; SIF = 50%) over a time span of 16 h, in contrast to native gelatin or rosin gum where under identical conditions the release exhausted within 7 h and 10 h, respectively. The release profile followed the first-order kinetics and the diffusion exponent (n) values obtained from the Korsemeyer−Peppas model ranged between 0.5