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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.

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.

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...

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.

Rosin was used to treat round bamboo culm using the impregnation method. The quantitative color and gloss measurements combined with a qualitative eye tracking experiment were used to evaluate the effect of rosin treatment under different temperatures on the visual characteristics of the bamboo surface. Surface morphology analysis was also used to explore the mechanism of modification. The results showed that proper heating of the modified system was conducive to the formation of a continuous rosin film, which increased the gloss value. The maximum gloss value of 19.6 achieved at 50 °C was 122.7% higher than the gloss value of the control group. Heating decreased the brightness of the bamboo culm and changed the color from the green and yellow tones to red and blue. Additionally, at temperatures higher than 60 °C, the bamboo epidermal layer was damaged or shed, and stripes formed on the culm surface. The density of these stripes increased with an increase in treatment temperature. Eye movement experiment and subjective evaluation showed that high gloss would produce dazzling feeling, such as at 50 °C, while low gloss will appear dim, such as at 80 °C, while the gloss at 40 °C and 60 °C were appropriate. Additionally, the solid color surface below 60 °C had a large audience of about 73%, and the striped surface above 60 °C was preferred by 27% of the subjects.

The rosin flux is commonly used in the welding process of the thick-film components for DC/DC power supply circuits. Under certain conditions, the organic acids in the flux react with Si-Al wire and hence diminish the wire bonding strength. Based on the reaction mechanism between Si-Al wire and flux, this paper investigates the impact of rosin flux on the bonding strength of Si-Al wire at the interface of Au. In particular, the micro-structure change of the bonding interface versus standing time of flux is researched with microscopic methods. The experimental results show that the rosin flux has a great influence on the bonding strength of the thick-film gold interface when the standing time is more than 6 hours. The wire bonding strength declines due to the dendritic structure formed in Si-Al wire. It is found that, by accurately controlling standing time of the flux, the reliability of wire bonding strength is significantly improved.

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...

At present, renewable and biodegradable biocomposites materials have drawn much attention as promising green materials in different domains of application such as intelligent food packaging, biomedical and drug delivery, bio-membranes, automotive, as well as in industrial composting applications. The current review deals with the advances in preparation methods and technical applications of these biocomposites. Different biomass materials obtained from renewable resources such as coffee grounds (CG), nanocellulose and date stones are developed to be used as smart reinforcing agents in biodegradable biopolymers for improving their overall properties. Conversely, some drawbacks are associated with the use of lignocellulosic materials as reinforcing agents, especially their high humidity absorption, poor wettability, and incompatibility with most biopolymers. Thus, novel processing techniques and different aspects are proposed in this review to produce high performance lignocellulosic reinforced materials with better properties. Facial and green modification of organoclay (OC) by antibacterial natural rosin and stearic acid to obtain toxicity-free expanded OC is also discussed. Green modification using OC can also be used as compatibilizing and reinforcing material for different incompatible biopolymers such as chitosan, carboxy methyl cellulose (CMC) and polylactic acid (PLA). Ultimately, the future vision on the challenges and the environmental issues towards CO2 emission which is associated to the risk assessment of these bionanomaterials are also discussed.

In this paper, the compound hot-melt adhesives were prepared by blending alkyl sulfonate polymer antistatic agent with modified rosin hot-melt adhesive and used for the preparation of polyethylene film/polypropylene-coated non-woven fabrics. The effects of the amount of antistatic agent on the melt viscosity, softening point, and thermal stability of the compounded hot-melt adhesives were studied. Then, the antistatic properties and its washing fastness of the coated non-woven fabrics were tested and analyzed. The results showed that the softening point and the melt viscosity of the hot-melt adhesives decreased after compounding, and the thermal stability of the compound hot-melt adhesives decreased in the high temperature range, which was not affected before 200℃. The surface inductive voltage, half-life, and specific resistance of the coated non-woven fabrics prepared from the compound adhesives decreased gradually with the increase of the amount of the antistatic agent, indicating that the antistatic property of the prepared fabrics was gradually improved. In addition, the fabrics still exhibited antistatic properties after soaping for several times. The influence of compound adhesive on the wettability of fabric surface was consistent with that of antistatic property. Finally, the mechanism of the hot-melt adhesive and antistatic agent compounding technology to improve the antistatic performance of the coated non-woven fabrics was elaborated, and the reason for its excellent soaping durability was also explained.

The viscoelastic properties of wood samples treated with various consolidants [polyethylene glycols (PEGs), lactitol and trehalose, Kauramin, polydimethylsiloxane (PDMS) and trimethoxymethylsilane (MTMS), rosin and polyethylene-L-tartaramide] were evaluated by means of dynamic mechanical analysis (DMA) in order to clarify their effects with regard to the conservation of wood objects. Two softwoods, medium-decayed silver fir (Abies alba) and highly decayed maritime pine (Pinus pinaster), and two differently decayed oak hardwoods (Quercus spp.) were used. In addition, the selected parameters [retention, volume variations and equilibrium moisture content (EMC)] were evaluated to assess the consolidation efficacy. The results showed that in treated wood, both the storage modulus and tanδ depend upon the level of degradation. The impact of the consolidating product was greater in more degraded wood (a higher product amount inside the artefact) compared to well-preserved material, where also wood played a role (also when the products were applied at high concentrations). The values of the different viscoelastic parameters also depend upon the ability of the products to interact with the wood matrix; this characteristic is fundamental to the nature of each consolidant. Lactitol-treated samples showed the highest stiffness increases, whereas those treated with selected PEG combinations and rosin displayed noticeable tanδ increases (high dissipative behaviour).

Introduction of bio-composites into aircraft interior and airframe secondary structures is subjected to major technical challenges such as the enhancement of mechanical, thermal, electrical and electromagnetic shielding properties of bio-sourced materials. In this paper, electrical conductivity and electromagnetic shielding effectiveness of two bio-composites have been studied by tests and numerical models. Two monolithic composites with partly bio-based content were manufactured. The first bio-composite is made of a carbon fibre fabric prepreg and a partly bio-based (rosin) epoxy resin (CF/Rosin). The second bio-composite is a combination of prepregs of carbon fibre fabric / epoxy resin and flax fibre fabric / epoxy resin (CF-Flax/Epoxy). A single line infusion process has been used prior to the curing step in the autoclave. Both variants are exemplary for the possibility of introducing bio-based materials in high performance CFRP. In-plane and out-of-plane electrical conductivity tests have been conducted according to Airbus standards AITM2 0064 and AITM2 0065, respectively. Electromagnetic shielding effectiveness tests have been conducted based on the standard ASTM D 4935-10. Materials were prepared at the German Aerospace Center (DLR) while characterization tests were conducted at the University of Patras. In addition to the tests, numerical models of representative volume elements have been developed using the DIGIMAT software to predict the electrical conductivity of the two bio-composites. The preliminary numerical results show a good agreement with the experimental results. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 690638 and the Special Research Plan on Civil Aircraft of Ministry for Industry and Information of the People’s Republic of China (MIIT) under Grant No MJ-2015-H-G-103.

A high temperature epoxy resin was formulated by using a rosin-sourced anhydride-type curing agent, i.e., maleopimaric acid (RAM), and a two-component epoxy consisting of an E51-type epoxy and a solid phenolic epoxy to form a bio-sourced green matrix resin. The glass transition temperature of the final resin was 238 &deg, C Carbon fiber composite prepreg and was manufactured and laminated into composite specimens. Interleaving Toughening Technology (ITT) was applied to the laminates by using Polyamide interleaf veils. The interlaminar fracture toughness and compression after impact (CAI) strength were investigated and showed that the opening Mode I interlaminar fracture toughness GIC and the Mode II interlaminar fracture toughness GIIC of the specimens with interleaves were significantly improved from 227.51 J/m2 to 509.22 J/m2 and 1064.3 J/m2 to 1510.8 J/m2, respectively. Correspondingly, the drop-weight impact test shows that the interleaves reduced the impact damage area from 20.9% to 11.3% of the total area, and the CAI residual strength was increased from 144 MPa to 191 MPa. Meanwhile, mechanical tests showed that the in-plane properties of the interleaved laminates were slightly reduced due to carbon fiber volume fraction reduction. In conclusion, the high glass transition temperature, fracture toughness and CAI behaviour make the green resin matrix composite a potential candidate for aerospace applications.

Rosin is a naturally available organic material obtained especially from pine trees. It finds many usages and applications in areas like soldering, pharmaceuticals, building work, engineering field etc. In this work, an attempt has been made to study experimentally the improvement in strength of rosin at normal stove top temperature by means of combining rosin in various ratios with some important organic hardeners and chemicals of literature importance. A table top book press was fabricated for the purpose of rosin pressing using simple tools like teak wood, bolt and nuts. Experiments were conducted using commonly used kitchen gas stove, fabricated book press, rosin raw material, aluminium sulfate powder, maleic anhydride chemical, acetone, ethanol and saw dust particles for making different combination materials using rosin as the main element. Results showed that, rosin on its own without additives showed higher viscosity and brittleness. When combined with organic hardener aluminium sulfate, rosin produced an improved material with reduced brittleness, good hardness and good energy absorption. And by combining with maleic anhydride chemical, rosin produced a hard monomer with an improvement in energy absorption with better future scopes. Comparatively better material was obtained using saw dust particle reinforced rosin and chemical hardener combination. Improvement in characteristics like viscosity and energy absorbed were observed using experiments at three different temperatures. With this improvements, rosin promises to be a possible future material or material additive like filler in composites with regard to anti-plastic materials or plastic alternatives.

Polybutylene adipate-co-terephthalate (PBAT) is a biodegradable polymer with good features for packaging applications. However, the mechanical performance and high prices of PBAT limit its current usage at the commercial level. To improve the properties and reduce the cost of PBAT, pine resin derivatives, gum rosin (GR) and pentaerythritol ester of GR (UT), were proposed as sustainable additives. For this purpose, PBAT was blended with 5, 10, and 15 wt.% of additives by melt-extrusion followed by injection moulding. The overall performance of the formulations was assessed by tensile test, microstructural, thermal, and dynamic mechanical thermal analysis. The results showed that although good miscibility of both resins with PBAT matrix was achieved, GR in 10 wt.% showed better interfacial adhesion with the PBAT matrix than UT. The thermal characterization suggested that GR and UT reduce PBAT melting enthalpy and enhance its thermal stability, improving PBAT processability. A 10 wt.% of GR significantly increased the tensile properties of PBAT, while a 15 wt.% of UT maintained PBAT tensile performance. The obtained materials showed higher hydrophobicity than neat PBAT. Thus, GR and UT demonstrated that they are advantageous additives for PBAT&ndash, resin compounding for rigid food packaging which are easy to process and adequate for industrial scalability. At the same time, they enhance its mechanical and hydrophobic performance.

Polysaccharide chitin (CH) was modified by antimicrobial natural gum rosin as a biocompatible agent within the thermoplastic polyurethane (TPU) elastomer to form the TPU/CH composite. This blend was then mixed with different ratios of ZnO-doped-SiO2 nanoparticles (ZnO-SiO2-NPs) to chelate chitin and to improve the properties of TPU nanocomposites. The topology and surface roughness of chitin and nanoparticles within the TPU matrix, besides their effect on the crystallinity degree of TPU were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). The TPU nanocomposites are subjected to different measurements such as mechanical, thermal, hydrophobicity, flammability, water vapor, and oxygen barrier properties, as well as antimicrobial activity. The results showed that the major properties were improved when the nanoparticles were added, especially at 5 wt%. Furthermore, the TPU/CH blend reinforced with high contents of NPs (i.e., 5–7 wt%) exhibited efficient antimicrobial activities against Gram-negative, Gram-positive bacteria and, pathogenic fungi.

Curcumin (CUR) chewing gums have potential therapeutic benefits to head and neck cancer patients. The objective of this work was to develop medicated chewing gums (MCGs) with high CUR loading and desirable mastication properties. This was accomplished by evaluating the effect of five gum ingredients: (X1) polyisobutene, (X2) polyvinyl acetate, (X3) wood rosin, (X4) wax, and (X5) CUR on the mechanical properties of the MCGs using a 25-run, five-factor, two-level D-Optimal mixture design. CUR MCGs were prepared by the conventional fusion method for making chewing gums. They were characterized by a two-bites texture and uniaxial tension tests to generate force–displacement curves from which the cohesiveness (Y1), springiness (Y2), chewiness (Y3), compressibility (Y4), resistance to extension (Y5), and extensibility (Y6) were measured. Observed responses were used to generate polynomial models correlating the independent with the dependent variables. Elasticity and stiffness of the gums were found to be readily impacted by PIB and CUR levels. Fitted models were then used to predict a gum composition that has comparable mechanical properties to commercially procured chewing gums. The optimized MCG was loaded with 50% of either CUR or CUR/SBE-β-CD inclusion complex and tested in vitro for drug release. Although no differences in mechanical properties were observed, substituting CUR with the inclusion complex was found to significantly enhance drug release. This study highlighted the impact of each gum ingredient on the quality of the MCGs and demonstrated the feasibility of preparing chewing gums with up to 50% drug loading.

International audience; The temperature of pine rosin softening point was studied to better understand the phenomenon of resin exudation on the surface of pine boards. This problem may decrease strongly the aesthetical performance of wood used outside and is an important concern for the industry. To perform a reliable measurement of rosin properties with a small amount of sample, differential scanning calorimetry (DSC) and thermo mechanical analysis (TMA) techniques were investigated and the results compared. DSC curves on industrial rosin and acetone rosin extractives from maritime pine show a behavior similar to a glass transition in polymers. TMA measurements carried out on the same industrial rosin showed that the softening point is in the midpoint of the transition phase observed by DSC. The softening point temperature is about 45 °C for industrial rosin and about 50 °C for rosin extractives from maritime pine boards. These values are significantly lower than those usually found on other rosins measured by the ASTM E28-14 standard using the ring-and-ball method. When using heat treatment, it was observed for the first time that the thermal history of the sample can change its softening point temperature. With these results, it could be possible to develop a new strategy to reduce rosin exudation for exterior wood siding.

This work investigates the effect of a polycarboxylate superplasticizer (SP) and a rosin resin type air-entraining agent (AE) on the rheological properties of powder-viscosity modifying admixture (VMA) combination type self-compacting concrete (SCC). The modified Bingham model was applied to describe the shear thickening behavior of this specific SCC. The results showed that both the yield stress and plastic viscosity of SCC deceased significantly while the shear thickening behavior of mixtures was intensified with an increase of SP dosage. The addition of AE led to an increase of yield stress and a decrease of plastic viscosity, whereas a high air content weakened the shear thickening behavior of SCC. The shear thickening behavior was found to be completely disappeared and shear thinning behavior occurred when the air content reached 8.7%, which indicated that increasing the air content was an easy and effective way to reduce the shear thickening behavior of SCC.

A poly(lactide-b-β-methyl-δ-valerolactone-b-lactide) (LVL) triblock copolymer was used to create fully sustainable pressure-sensitive adhesives (PSAs) that have promising commercial viability due to the low cost of both monomers. A common rosin ester tackifier was found to preferentially solubilize the midblock and was miscible up to 50% by weight. It was used to lower the modulus of the LVL triblock to satisfy the Dahlquist criterion. Small amplitude oscillatory shear, nonlinear shear creep, and uniaxial extensional data were correlated to tack, 180° peel, and shear resistance adhesion results. “Viscoelastic windows” were constructed for PSAs with 30%, 40%, and 50% tackifier and were used to identify potential candidates for general-use PSAs like Post-it® Notes.

Natural and bio-based thermal insulation materials play an important role in the lifecycle impact of buildings due to their influence on the amount of energy used in indoor temperature control and the environmental impact of building debris. Among bio-based materials, cork is widespread in the Mediterranean region and is one of the bio-based materials that is most frequently used as thermal insulation for buildings. A particular problem is the protection of the cork-agglomerated panels from external stress and adverse weather conditions; in fact, cork granulates are soft and, consequently, cork panels could be damaged by being hit or by excessive sun radiation. In this study, an innovative external coat for cork-agglomerated panels made of a blending composite of beeswax and rosin (colophony) is proposed. The performance of this composite, using different amounts of elements, was analysed to discover which mix led to the best performance. The mix of 50% beeswax and 50% rosin exhibited the best performance out of all the mixes. This blend demonstrated the best elongation and the lowest fracture density, characteristics that determine the durability of the coating. A performance comparison was carried out between cork panel samples coated with lime render and beeswax–rosin coating. The coating of beeswax and resin highlighted a detachment value about 3.5 times higher than the lime plaster applied on the side of the cork.

The information of rosin penetration and distribution along the longitudinal axis of round bamboo culm is of great significance for hydrophobic treatment of round bamboo with rosin. In this study, mercury intrusion porosimetry and scanning electron microscopy were used to determine the rosin distribution at the cellular and subcellular levels. The results showed that rosin penetrated to the middle of bamboo culm with a length of 150 mm from both ends. For the longitudinal direction of bamboo culm, rosin is concentrated in the two ends of bamboo culm, and almost evenly distributed in the rest parts. Moreover, rosin mostly penetrated into small pores (diameter ≤ 0.08 μm), while larger pores such as lumen (diameter > 8.00 μm) were penetrated less. The results of water permeability tests showed that both water absorption and absorption rate gradually decreased along the longitudinal axis, which coincides with the amount of penetrated rosin.

This study reports the synthesis of rosin-based epoxy and imidoamine curing agent encapsulated microcapsules for self-healing coatings. The microcapsules were prepared through an in-situ polymerization technique and were characterized via particle size analysis and scanning electron microscopy (SEM). The core content analysis was done using the extraction method and further verified via FT-IR and 1H NMR spectroscopy. The stability of synthesized microcapsules was evaluated by solvent wash testing and thermal degradation analysis using thermogravimetric analysis (TGA). The self-healing coatings were applied on mild steel specimens using rosin-based epoxy/imidoamine containing 10 wt% & 20 wt% epoxy microcapsules and both 10 wt% epoxy & 10 wt% curing agent microcapsules. The self-healing effect was examined by applying artificial scratches to the prepared coatings which displayed healing of the scratched planes within 24 h. Also, salt spray, adhesion, and tensile tests were conducted on the coated specimens with and without microcapsules to determine the chemical resistance and mechanical strength of self-healing coatings. The epoxy/imidoamine coating containing both 10 wt% epoxy & 10 wt% curing agent microcapsules exhibited preeminent performance among all.

The unique features of cellulosic paper including flexibility, biodegradability, and low cost enables it as a versatile, sustainable biomaterial for promising applications. In the paper industry, microsized mineral particles are widely used in the production of printing/writing paper grades, while rosin derived from trees is the earliest internal sizing agent for paper hydrophobication. On the basis of existing commercial practices associated with the use of mineral particles and rosin in paper production, we present a process concept of converting cellulosic fibers (paper-grade pulp) into "sticky" superhydrophobic paper involving the use of microsized mineral particles and rosin (a tree-derived natural product, mainly a mixture of resin acids, especially abietic acid with chemical formula of C19H29COOH). Internal filling of cellulosic networks with mineral particles was basically used to hold out the mineral particles added at the surface, and the delicate integration of wet-end/surface applications of mineral particles with paper surface engineering with rosin/alum led to the development of "sticky" superhydrophobicity, i.e., ultrahigh water-repellency and strong adhesion to water. This proposed concept may provide valuable implications for expanding the use of paper-based products to unconventional applications, e.g., ultrahigh-performance ink jet printing paper for mitigating the "coffee-ring effect" and paper-based microfluidic devices for biomedical testing.

Wood polymer composite (WPC) recognized as sustainable green polymer composite is widely used for its high durability, low maintenance, acceptable relative strength and stiffness, economy relative to other competing materials, and the fact that it is derived from a natural resource. This paper recounts the fabrication and investigation of physico-mechanical properties of Sagwan Teak Wood Flour/Polyester Composites with and without gum rosin binder. Polyester/wood flour ( Tectona grandis ) composites with and without gum rosin were fabricated in a wide range of compositions by hand lay-up technique. Wood flour (WF) percentage was varied from 5 to 20% by weight and tensile, flexural, impact and three-body abrasive wear tests were performed to the as-fabricated composites. It was observed that WPC having 10 wt% WF had the best tensile and impact strength. At this optimum weight percentage of wood flour (i.e. 10 wt%), the polyester resin was further blended with various wt% natural gum rosin and the sustainable composites were further optimized for best mechanical properties. The ranking of all these composites has been evaluated by TOPSIS technique by optimizing the various properties. TOPSIS optimization demonstrated that the composite consisting 10% WF mixed with 15% gum rosin yielded excellent impact strength, high abrasive wear resistance and high ductility as demanded in sandwich composite material.

Rosin-based antifouling paint with the incorporation of butenolide, a promising antifoulant, possesses the potential to deter the settlement of marine organisms on submerged surfaces. With the purpose to extend the antifouling duration, this research investigated the respective contribution of paint ingredients, including butenolide concentrations (5%, 10% and 15%), pigment choices (TiO2, Fe2O3, Cu2O and ZnO) and binder compositions (acrylic copolymer to rosin at 1: 2.5, 1.5: 2 and 2.5: 1), to the field antifouling performance of butenolide. A raft trial was carried out at Yung Shue 0, Hong Kong after the application of antifouling paints on PVC panels. Biofouling dynamics on panel surfaces, such as coverage percentage and biomass accumulation, were monitored until submersion for 6 months to allow for the assessment of antifouling efficiency. Field results showed that butenolide incorporation generally inhibited the settlement of fouling species on the coated panels as demonstrated by the decreased surface coverage and biomass weight. Coatings with 1: 2.5 paints containing 10% butenolide exhibited the best antifouling performance with only 34% of the surface covered by fouling organisms, which mainly consisted of algae and slime. The smallest biomass increase of the fouling community was also observed for 1: 2.5 coatings. An increased proportion of rosin in binder compositions yielded better antifouling performance following the order of 1: 2.5 > 1.5: 2 > 2.5: 1. Laboratory experiments were also conducted to examine the behavior of paint coatings in stirring artificial seawater. Butenolide addition decreased the film hardness and inhibited water uptake, but resulted in weight loss of paint coatings. Along with the gradual release of butenolide, the hardness of paint films increased gradually. Overall, a service life of 6 months, while eliminating the use of heavy metals, highlights the effectiveness of butenolide-incorporated paint formulation, especially 1: 2.5 paint, as an environmentally benign and fouling-resistant candidate for future antifouling application.

We have designed an innovative protocol for the consolidation of waterlogged archaeological woods by using acetone mixtures of halloysite clay nanotubes and a chemically modified colophony (Rosin). Firstly, we have investigated the thermal properties of HNTs/Rosin nanocomposites, which have been prepared by means of the casting method from acetone. The HNTs content have been systematically changed in order to study the influence of the inorganic filler on the thermal stability and glass transition process of Rosin. We have observed that the thermal properties of the hybrids are affected by the specific HNTs/Rosin interactions. Then, acetone dispersions of HNTs/Rosin composites at variable filler content have been employed as consolidants for waterlogged archaeological woods. The quantitative analysis of the thermogravimetric curves have provided the amount of consolidants entrapped into the wood structure. These results have been successfully correlated to the consolidation efficiencies estimated from the analysis of the wood shrinkage volume upon drying. The attained knowledge represents the basic step to develop a green protocol for the long term protection of wooden art-works. © 2017, Springer Science+Business Media B.V.

In this study, a novel bio-based thermosetting system has been developed from epoxy resin (EP), with rosin-sourced anhydrides (maleopimaric acid, RAM) as curing agent and imidazole type latent catalyst (two amino imidazole salt complex, IMA), to be used as matrix for hot-melt prepreg curing at mid-temperature. For comparison, the epoxy resin system with petroleum sourced hardener methylhexahydrophthalicanhydride (MHHPA) was also examined. The curing behaviour and mechanism were investigated by non-isothermal differential scanning calorimeter (DSC) analysis and Fourier transform infrared (FTIR) spectra. The results showed that the curing course of bio-based epoxy resin system containing RAM included two stages, which were the reaction between the free carboxyl group of RAM and oxirane ring under the acceleration of IMA, and the main reaction attributed to the reaction between anhydride and oxirane. According to Kissinger method, the reaction activation energy (E a ) of two stages were 68.9 and 86.5 kJ mol‒1, respectively. The E a of EP/MHHPA and EP/IMA resin system were 81.04 and 77.9 kJ mol‒1. The processing property of EP/RAM/IMA system, i.e. the relationship between viscosity-temperature-time, was characterized by cone-plate viscometer aim to decide the processing parameter of prepreg preparation. The effect of RAM content on mechanical performance and dynamic mechanical property was investigated. Noteworthily, compared with the laminates with EP/MHHPA as matrix, the laminates with RAM as hardeners achieved a 44%, 73% and 70°C increase in bending strength, bending modulus and the glass transition temperature, respectively, due to the bulky hydrogenated phenanthrene ring structure incorporated into the cross-linking networks. When the fiber volume fraction reached 47%, the mechanical property of the laminates prepared with hot melt prepreg was superior or comparable to that of composites with pure petroleum sourced matrix. RAM as cross-linking agent of epoxy resin holds a great potential to satisfy the requirement of composites such as structure and secondary structure parts preparation.

International audience; The use of biodegradable polymers is of great importance nowadays in many applications. Some of the most commonly used biopolymers are polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) due to their superior properties and availability. In this manuscript, we use a facile and green modification method of organoclay (OC) by antimicrobial natural rosin which is considered as a toxicity-free reinforcing material, thus keeping the green character of the material. It increases the interlayer spacing between the clay platelets. This was proven by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) and found to impart antimicrobial properties to PLA/PBAT blends. The morphology of the resulting blends was conducted using scanning and transmission electron microscopies (SEM and TEM), and evidence of exfoliation and intercalation was observed. The thermal properties of the blends were studied using differential scanning calorimetry (DSC), and a detailed study of the crystallization of both PLA and PBAT was reported showing cold crystallization behavior of PLA. The final effect on mechanical and antimicrobial properties was also investigated. The obtained results reveal excellent possibility of using expanded OC modified PLA/PBAT polymer blends by adding a green material, antimicrobial natural rosin, for food packaging and biomembranes applications.

The incorporation of metallic nanoparticles (NPs) into a biomass-based matrix has been intensively investigated because the obtained nanocomposites exhibited effective antibacterial activity to intractable resistance of bacteria. However, the nanocomposites present limitations, such as a multi-step preparation process and a low loading capacity of nanoparticles. A facile preparation route for the preparation of antibacterial metallic nanocomposites would be especially beneficial for industrial fabrication. In this study, we provided a facile strategy for the preparation of a rosin-derived biochar matrix loaded with silver nanoparticles (Ag NPs) as the fillers. The results demonstrated that the preparation of these rosin-derived biochar silver nanocomposites (Rc/Ag nanocomposites) was achieved by a rapid pyrolysis process and a large amount of Ag NPs were in-situ obtained and homogeneously dispersed on the matrix. More importantly, these materials exhibited satisfying antibacterial activities against E. coli and S. aureus. Thus, the Rc/Ag nanocomposites exhibit promising filler for wooden furniture against bacterial infection and could be used as a filter for indoor antibacterial air filtration.

Acknowledgements: This work is supported by the Fundação para a Ciência e a Tecnologia (FCT) and Centro2020 through the Project references: UID/Multi/04044/2013; PAMI – ROTEIRO/0328/2013 (Nº 022158) and MATIS (CENTRO-01-0145-FEDER-000014 – 3362). Rosins are the non-volatile exudates of pine resins with hydrophobic characteristics that are widely used as a precursor for many industrial applications. In this paper we discuss the nature, process and its applications as a matrix for a composite material for additive manufacturing. The composite material has been tailored to chemical and mechanical properties with respect to their applications. info:eu-repo/semantics/publishedVersion

International audience; The interactions between rosin and turpentine during the drying process were studied to better understand wood pine resin exudation in outdoor use under solar heat. Resin exudation is an important concern for industrials, as it may strongly decrease the wood’s aesthetic value. Resin viscosity change with temperature variations induced an alteration in the resin’s appearance from 65 °C. Resin, which is opaque at ambient temperature, becomes translucent above 65 °C. Resin samples were dried at temperatures respectively lower and higher (60 °C and 90 °C for 16 h) than the threshold. For all measurements, eight resins from different trees were harvested using an isolation technique developed by Biogemme®. After drying, samples were kept at room temperature, and the softening point temperature and the remaining turpentine amount were measured over time using Thermomechanical Analysis (TMA) and Thermogravimetric Analysis (TGA) respectively. After three months, the results show that a majority of samples dried at 90 °C have a softening temperature under 25 °C, while all the samples dried at 60 °C have a softening temperature above 60 °C. These results can be explained by a modification of the physical properties of the samples dried at 90 °C: they start to behave like gels, preventing the evaporation of their liquid phases. These new results highlight some properties of resin that may be interesting to develop a new strategy for reducing resin exudation on outdoor wood siding, by fixing the resin inside the wood during the industrial drying process.

This paper studied two alternative polymeric films based on natural latex and rosin as a waterproofing coating for 3-layer sugarcane-bamboo-based particleboards (3LP). To study the roughness as well as evaluate the coating surfaces on the 3LP, scanning confocal electron microscopy (SCEM) was used. The wettability performance of the coatings was evaluated by the surface energy through the contact angle method. The 3LP coated thermal, physical and mechanical properties were evaluated following ASTM-E1530: 2011 and ABNT NBR 14810 standards, respectively. Physical results indicated latex and rosin coatings significantly decreased water permeability in the 3LP showing swelling in thickness (TS) values of 1.72 and 2.43%, respectively, when compared 3LP without coating (3LP-Control) of 12.90%. The latex and rosin coatings on the 3LP did not influence the thermal properties. Mechanical properties of modulus of rupture (MOR)and modulus of elasticity (MOE) under bending solicitation shown that all 3LP met the ANSI Standard A208.1–1999 requirements. Latex successfully formed a smooth and continuous film which covered the surface pores of the 3LP, whereas rosin did not form a smooth and continuous, forming only a thin film on the 3LP.

Round bamboo culm maintains the natural texture, shape, and mechanical structure of raw bamboo materials compared with modern bamboo engineering materials, which break down bamboo culms into small elements. Promoting the use of round bamboo is an efficient and sophisticated way to utilize bamboo resources. However, the high hygroscopicity and poor dimensional stability are disadvantages that obstruct the utilization of round bamboo culm in construction and building applications. To solve these problem, rosin was used to modify the bamboo culm material in this work. The results show that the weight percentage gain of rosin was 9.98% after 8 h of impregnation. Part of the rosin formed transparent hydrophobic films on the surface of the bamboo culm, and decreased its surface wettability. Moreover, rosin was introduced into internal pores of bamboo where it decreased the porosity and total pore volume of bamboo by 14.42% and 23.81%, respectively. Additionally, the moisture absorption for 144 h at 65% relative humidity decreased by 39.27%, while rosin treatment decreased the swellings of wall thickness and diameter of bamboo culm from oven-dry to water saturation by 42.20% and 25.40%, respectively.

Carbon-neutral policy and technological race on the powder coatings market force to develop more advanced, safer, cheaper, and naturally sourced products. To meet the market needs, powder coating compositions and coatings were prepared from safe and natural-origin hardeners, resins, and fillers prepared from rosin, bio-diols, bio-epichlorohydrin, and halloysite, to investigate their thermal, mechanical, and functional properties in comparison with petroleum-based references: cross-linking behavior, glass transition temperature, thermal stability, hardness, cupping resistance, adhesion, chemical resistance, gloss, color, and anti-corrosive behavior in salt chamber. As a result, compositions containing up to 83 wt.% of natural resources, and showing comparable or better properties, as compared to references, were successfully prepared. Their application includes binders for future ecological powder paints for demanding protection of steel substrates.

Although polyurethane pressure-sensitive adhesives (PSAs) have been widely used, there are still some deficiencies in adhesion and heat resistance. To make up for these shortcomings, rosin is introduced into polyurethane/polysiloxane copolymer to improve its heat resistance and adhesion, while its hydrophobicity is also improved. The vinyl-terminated polyurethane/polysiloxane copolymer is synthesized by a one-pot polymerization method, and finally PSA with different content of rosin is obtained by UV radiation. The effects of rosin on heat resistance, hydrophobicity, viscoelasticity, adhesion and antibacterial of PSA have been studied. The results show that the heat resistance index, the contact angle and the peel strength of PSA are increased by 4%, 31 % and 88 % respectively when rosin content is 6 wt%. In addition, the storage modulus and loss modulus of PSAs enhance with the increase of frequency, and the storage modulus of PSAs is always higher than the loss modulus. All PSAs have good antibacterial properties, with an antibacterial rate above 99.2 %. This will help expand the application of polyurethane/polysiloxane PSA such as food packaging materials.

Bamboo is an eco-friendly and sustainable material that has great potential in construction. However, the excellent hydrophilic properties of bamboo restrict its further application in building materials. Rosin is a natural resin with low molecular weight. Its main component is resin acid, which is highly hydrophobic. It is also an eco-friendly material for treating bamboo. The objective of this study was to improve the hydrophobicity of bamboo with rosin. A rosin-ethanol solution was prepared, and bamboo was subjected to vacuum pressure impregnation with this solution at room temperature. During treatment, the rosin retention rate in bamboo increased rapidly with increased soaking time and tended to become stable after 4 h. After rosin treatment, the water uptake of bamboo decreased by 24.7%, meanwhile the swelling coefficient from air-dry to water-saturated conditions in the radial and tangential directions decreased by 23.11% and 21.36%, respectively. The water vapor sorption behavior of bamboo was investigated using a dynamic vapor sorption apparatus, and the results were analyzed using the Guggenheim-Anderson-de Boer model. After rosin treatment, the sorption isotherms of bamboo were still type II, with a decrease in the equilibrium moisture content of bamboo across relative humidity values. Bamboo surface wettability also decreased after rosin treatment, with an initial contact angle of 93°. Scanning electron microscopy revealed that the rosin formed a continuous and uniform film on the surface of bamboo and covered the vessels and pits.

Room temperature vulcanized (RTV) silicone rubber shows many excellent properties, but its applications are limited due to the poor mechanical properties. To improve the mechanical properties of RTV silicone rubber, dehydroabietic acid-modified glycidyloxypropyltriethoxysilane (DAG) was firstly used as the cross-linking agent to select a best DAG modified RTV silicone rubber with higher tensile strength of 0.65 MPa (DAG/RTVSR). Then different amount SiO2 was added to prepare the SiO2 reinforced DAG/RTVSR and further enhance the properties. The micro- morphology of RTVSR, DAG/RTVSR, and SiO2-DAG/RTVSR confirmed the uniform dispersion of DAG and SiO2, which results a well chain entanglement and increasing intermolecular interaction. Then, SiO2-DAG/RTVSR exhibit an obvious improvement of mechanical properties and thermal stability compared with unmodified RTVSR and DAG/RTVSR. This work indicates that the mechanical properties and thermal stability of RTV silicone rubber can be effectively enhanced by the synergistic effect of rosin derivative DAG and SiO2.

A series of bio-based non-isocyanate polyurethane (NIPU) coatings were successfully prepared via the ring-opening polymerization of rosin-based cyclic carbonate with amines. Then the NIPUs were modified with epoxy and cyclic carbonate-functionalized polyhedral oligomeric silsesquioxanes (POSS) to form NIPU/POSS coatings, respectively. The properties of the NIPU and NIPU/POSS coatings were determined, and the influences of POSS on mechanical and thermal properties of the resulting coatings were investigated. The results showed that by introducing POSS into the NIPU networks, the water tolerance, pencil hardness and thermal stabilities of the NIPU/POSS coatings were improved obviously with the increasing of the POSS content, but the impact strength, adhesion and flexibility of NIPU/POSS coatings were not observed to be affected to a significant extent.

A bio-based shape memory epoxy resin (DGEAPA) was synthesized from rosin to achieve the sustainability of shape memory epoxy resin, and its chemical structure was determined by FTIR and 1H NMR. For comparison, a petroleum-based epoxy, diglycidyl ester of terephthalic acid (DGT) having one benzene ring, was also synthesized. The properties, including thermal and mechanical properties, as well as shape memory properties of the epoxy resins cured with poly(propylene glycol)-bis (2-aminopropyl ether) (D230), were studied by differential scanning calorimeter, dynamic mechanical analysis, thermogravimetric analysis, tensile test, and U-type shape memory test. The effect of the stoichiometric ratio nDGEAPA/nDGT on the properties was studied as well. The thermal and mechanical properties, including thermal stability, glass transition temperature, tensile strength, and modulus of the cured epoxy systems, were found to be increased with DGEAPA incremental content, and the cured neat rosin-based epoxy system exhibited the highest properties. Both the cured rosin-based epoxy and the cured DGEAPA showed significant shape memory performance. Meanwhile, the rosin ring structure made the cured rosin-based epoxy systems display excellent shape recovery fixity, while small lower shape recovery and shape recovery rate relative to the cured neat DGT system. Therefore, the rosin-based epoxy resin has a great potential in the shape memory material applications.

Purpose This study aims to synthesize polyethylene glycol (PEG)-rosin derivatives from rosin and PEG for the production of solid soldering fluxes. The PEG-rosin derivatives would be water soluble, and the resulting solid soldering fluxes would have reasonable wetting ability when combined with a low-halide-content activator. Design/methodology/approach This paper presents a synthetic process for PEG-rosin derivatives. The reaction conditions (including catalyst type, catalyst concentration, reaction temperature and PEG type) were optimized for the synthesis of PEG-rosin derivatives. The chemical and physical properties of PEG-rosin derivatives were characterized by Fourier transform infrared spectroscopy, carbon-13 nuclear magnetic resonance spectrometry, differential scanning calorimetry and gel permeation chromatography. The production and characteristics of water-soluble rosin fluxes (WSRFs) were studied according to the standards of the Japanese Industrial Standards (JIS) Committees. Findings WSRs were successfully synthesized from rosin and PEG using 2 per cent ZnO as a catalyst, with a 2:1 molar ratio of rosin:PEG at 250°C over 9 h. The resulting WSRs were completely soluble in water. As the PEG3000-rosin had the highest melting point (55.2°C), it was chosen for the preparation of the WSRFs. Activators such as succinic acid, glutaric acid, ethylamine hydrochloride and diethylamine hydrobromide were selected for use in the production of the fluxes. It was found that WSRF 09 and WSRF 04 gave the best performance with the lead-free Sn-0.7Cu solder alloy in terms of good solderability, low halide content (less than 1,500 ppm), high insulation resistance and low corrosion. These fluxes were applied to produce solder pastes with Sn-3.0Ag-0.5Cu alloy and they passed the performance tests as expected for solder paste. Research limitations/implications Further studies are necessary on large-scale production and to compare the performance of these fluxes to those from conventional water-soluble fluxes currently available in the market. Application of these fluxes on low-temperature solder alloys such as SnZn and SnBi (Ren et al., 2016) worth further study. Originality/value The classification of flux systems according to the JIS 3283 standard does not specify PEG-rosin derivatives in the flux; nevertheless, ranking of the flux systems based on the halide content and corrosion properties of activators would be useful information when selecting flux systems for electronics soldering in water-washable applications. The application of these fluxes in solder paste gave very promising results and is worth investigating into more detail, as well as field test.

Composite films from sesame protein isolate and gum rosin were prepared at different ratios by casting method. The effect of gum rosin (GR) addition on the physical, mechanical, thermal, optical, and morphological properties were investigated. Maximum tensile strength and minimum water vapor permeability was observed for composite film at 80:20 ratio. Transparency of sesame protein film was observed to be lower as compared with composite films. ΔE values increased with increase in concentration of GR. X-ray diffraction of sesame protein film and composite films indicated amorphous structure of films. Differential scanning calorimetric curves of all films showed single Tg in the range of 108°C–158.66°C. All films exhibited weight loss in three stages (temperature ranged between 130°C and 590°C). Sesame protein film exhibited high degree of porosity. With the addition of GR porosity decreased and compactness increased. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers

The adhesion properties of magnesium oxide filled epoxidized natural rubber (ENR 25)/acrylonitrile-butadiene rubber (NBR) blend adhesives were studied using petro resin and gum rosin as tackifiers. Toluene was used as the solvent throughout the experiment. Five different loadings, i.e. 10, 20, 30, 40 and 50 phr magnesium oxide was used in the adhesive formulation. The SHEEN hand coater was used to coat the adhesive on polyethylene terephthalate at 30 and 120 µm coating thickness. The tack, peel strength and shear strength were determined by a Lloyd adhesion tester operating at 30 cm min−1. Results shows that all the adhesion properties of the ENR 25/NBR adhesives show a maximum value at 10 phr filler loading. Loop tack and peel strength pass through a maximum, an observation which is associated to the optimum wettability of adhesive on the substrate. For the shear test, maximum shear strength occurs due to the optimum cohesive strength of the adhesive. Results also show that all petro resin based adhesives have higher adhesion properties than gum rosin based adhesive. In all cases, the adhesion properties of adhesives also increase with increasing coating thickness.

In order to prepare bio-nanocomposites with no-cytotoxicity, the rosin-based epoxy resin (MPAER) and castor oil-based polyurethane (COPU) were synthesized and carbon nanotubes (CNTs) was used to enhance the properties of curing MPAER/COPU materials. The curing reaction, dynamic mechanical and thermal properties of this system were characterized by FTIR, NMR, DMA, TG et al. The cytotoxicity of materials is evaluated for HeLa cells using a MTT cell-viability assay. The results showed that COPU can cure MPAER and CNTs can increase effectively the properties of MPAER/COPU nanocomposites. The Tg of MPAER/COPU/CNTs has the highest value when CNTs content is 0.4 wt%, which is 52.4 °C higher than the pure MPAER/COPU. Thermal stability of the nanocomposites is enhanced by the addition of CNTs, the initial decomposition temperature Td5 of the sample No. 0.4 has increased from 284.5 to 305.2 °C, which is 20.7 °C higher than No. 0. The impact strength of the No. 0.4 film is 15 kg cm higher than the pure resin system. The survival rate of HeLa cells to the products is greater than 90% within 48 and 72 h, which demonstrate that this material has excellent biocompatibility and no obvious cytotoxicity for HeLa cells, which may be used in the medical treatment.