Addition Of Rosin Research Articles

Tough rosin-based reversibly crosslinked elastomers with anticorrosion and adhesion properties

Conventional polymer materials cannot repair hidden cracks that appear during use by themselves, which affects service life and reliability. The reversibility of dynamic covalent bonds provides an effective approach for the sustainable development of materials. In this study, we introduced rosin, a renewable resource, and dimethylglyoxime with an oxime bond into polyurethane elastomers to prepare tough, self-healing rosin-based crosslinked elastomers. Benefiting from their high crosslinking density, the prepared elastomers exhibit excellent mechanical properties (tensile strength up to 13.6 ± 0.5 MPa and toughness up to 21.3 ± 0.6 MJ m–3) and solvent resistance. Based on the dynamic reversibility of oxime–carbamate bonds, the elastomers exhibit excellent self-healing properties (97.2 ± 1.1 % self-healing efficiency for 3 h at 80 °C). Furthermore, the elastomers exhibit good adhesion and corrosion resistance. Notably, the addition of rosin improves the elastomers' hydrophobicity and heat resistance in addition to their mechanical properties. These findings suggest that the prepared self-healing rosin-based elastomers have promising applications in self-healing anticorrosive coatings and adhesives.

Construction of rough surface based on zein and rosin to hydrophobically functionalize cotton fabric with antibacterial activity

Hydrophobic and antibacterial functionalization of cellulosic fabric(cotton) were performed via a simple immersion process with two natural polymers: zein and rosin. Compared to zein-treated cotton fabric, the water contact angle (WCA) value of cotton fabric treated with zein-rosin complex increased from 119.62 ± 3.11° to 133.14 ± 2.5° and the water resistance was long-lasting. The micromorphology, roughness and chemical composition for the surface of different cotton fabrics were characterized by scanning electron microscopy, atomic force microscopy, infrared spectroscopy and X-ray photoelectron spectroscopy, respectively. The results showed that a rougher surface from zein was obtained with the addition of rosin, which contributed to the hydrophobic property of the fabric. In addition, the results showed that the functional cotton fabrics exhibited good antibacterial activity against E. coli and S. aureus and the bacterial inhibition rates were 92.2 % and 87.2 %, respectively. The functional fabrics retained their mechanical properties, air permeability and water vapor permeability.

Improvement of Microstructure and Properties of Q235 Steel by Iron-Based Laser Cladding Coating

Laser cladding is a repair and surface-strengthening technology for the protection of metal parts. It is an effective method for improving the properties of various metal substrates. The process involves melting and solidifying alloy powder on the surface of the substrate. The aim of the present study was to explore the effect of iron-based alloy laser cladding coating on Q235 substrate. Three types of specimens were obtained from Q235 base material using a 5 kW cross-flow CO2 laser beam. Sample 1 and sample 2 were obtained by the addition of rosin to the iron-based alloy powder. Sample 3 was obtained through the addition of rosin and vanadium to the iron-based alloy powder. A gas curtain was used to wrap the molten pool of samples 2 and 3. The surface hardness of the specimens was determined using a Rockwell hardness tester, and the tensile strength was evaluated using the universal mechanical testing machine. The microstructure of the cladding coating was explored using an Olympus optical microscope and SEM. The results showed that the average hardness of sample 2 and sample 3 was 6.42% and 19.84% higher than that of sample 1. The average tensile strength of samples 2 and 3 was 7.42% and 10.37% higher than that of sample 1. The grain of sample 3 was finer than that of sample 2, and that of sample 2 was finer than that of sample 1 under the same magnification. Rosin minimized oxidation of the substrate, whereas the gas curtain prevented the entry of air into the molten pool, hence the improved properties of samples 2 and 3 compared with that of sample 1. Rosin and the gas curtain protected the powder from oxidation loss and improved the quality of the cladding coating. The results of the present study show that rosin reduced the oxidation of iron-based powder, whereas vanadium improved the hardness and strength of the substrate as well as refined the grain size.

Peculiarity for the stability of three different emulsion explosives

An investigation was performed into the stability of three emulsion explosives, namely bulk, packaged and powdery emulsion explosive. The dynamic stability is crucial for bulk emulsion explosive, and the experimental results show that it will possibly achieve both good dynamic stability and fluidity when polyisobutene succinic anhydride (PIBSA) based emulsifiers, such as PIBSA-DTEA, PIBSA-TEA and PIBSA-STEA etc, used alone in preparing explosive. Opposite with that, the long-term storage stability is much more important for packaged emulsion explosive. In several PIBSA based emulsifiers, polyisobutene succinimide (PIBSI) is more suitable for improving the stability of packaged emulsion explosive. Moreover, the stability also can be improved through rising the toughness of oil film, like adding a certain amount of microcrystalline wax. The caking of ammonium nitrate (AN) crystals with time is the key reason, which decreasing the stability of powdery emulsion explosive. The caking phenomenon will be weakened with the addition of rosin because the softened rosin can allow the repair of damaged oil film and prevent AN crystals breaking the oil film. Besides that, adding potassium nitrate to AN solution or a certain amount of talcum powder also can effectively improve the stability.

The adjuvant effects of rosin and coconut oil on nicosulfuron and mesotrione to control weeds

Natural adjuvants are novel options to reduce the doses of chemical herbicides. The aim of the current study was to examine the compositions and adjuvant effects of rosin and coconut oil on herbicides using a combination of indoor experiment and field trial. The GC-MS results showed that the main component of rosin was abietic acid (40.02%), and the main components of coconut oil were 2-pentanone, 4-hydroxy-4-methyl- (21.45%) and dodecanoic acid (14.59%). In greenhouse experiment, rosin showed a significant adjuvant effect on nicosulfuron against Digitaria sanguinalis and Amaranthus retroflexus, with the GR50 ratios of 1.47 and 1.69, respectively. The GR50 values of nicosulfuron in the present of coconut oil were 3.99 and 10.13g a.i./hm2 against D. sanguinalis and A. retroflexus, lower than that of individual application. The adjuvant effect of rosin and coconut oil on mesotrione was also found. In field trial, the fresh weight control efficiency of nicosulfuron (45g a.i./hm2) and mesotrione (112.5g a.i./hm2) was significantly improved after the addition of rosin and coconut oil, similar with that of recommended dose. Rosin and coconut oil could reduce the contact angle of nicosulfuron, with the results of 56.68° and 53.90°, respectively, lower than that of individual application. Furthermore, rosin and coconut oil could decrease the surface tension, wetting and penetration time; and increase the spreading diameter and maximum retention. Both rosin and coconut oil have adjuvant effects on herbicides in the lab & field with multiple mechanisms. Thus, they have the potential to be developed into natural adjuvants for herbicide formulation to control weeds.

Effect of Impregnation with Boron Compound Doped Rosin to the Combustion Resistance of Oriental Beech Wood (Fagus orientalis Lipsky)

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.

Activated Carbon Production by Co-Pyrolysis of Vacuum Residue and Gum Rosin

Vacuum residue (VR) is potential to be used as a feedstock for mesophase pitch (MP) production because of its low cost and aromatic content. MP, which is a liquid-crystalline state of VR, may be used as precursor of activated carbon (AC). Gum rosin containing conjugated double bonds may be added to and can improve crystallinity and pore surface area in further processes of carbonisation and activation. In the present study, co-pyrolysis was carried out in a stirred tank reactor at 450°C with holding time for 120 minutes. The amount of gum rosin mixed with VR was varied 0, 5, 10 and 15% wt of VR. The precursor products had C/H mole ratio of about 2.43, 2.37, 2.28, and 2.01 by increasing gum rosin added. Subsequently, this precursor underwent carbonization at 700°C with holding time for 120 minutes under N2 flow and activation. KOH solution was used as activating agent to the precursor of activated carbon. Activated carbon gave higher surface area and lower C/H atom ratio with increasing gum rosin added during co-pyrolysis. With gum rosin addition, surface areas of ACs were 120.81, 194.56, 312.36, dan 462.19 m2/g, respectively, and crystallite sizes increased from 8 to 22 Å.

Process Variables and the Performance of Cationic Rosin as an Internal Sizing Agent in Recycled Corrugated Container Pulp

Cationic rosin has many uses in papermaking; however, its performance as an internal sizing agent differs depending on the circumstance, especially in the recycling of pulps. In this study, a comprehensive laboratory approach was used to investigate the process variables affecting the cationic rosin application in the paper recycling process. In this respect, four levels of alum (0.5, 1.0, 1.5, and 2.0%) and four levels of cationic rosin (0.5, 1.0, 1.5, and 2.0%) were considered to find the best alum/cationic rosin combination in acidic conditions (pH 5). After considering all aspects of the paper, such as the mechanical properties (tensile, burst, and tear indices), wet resistance (Cobb test and dynamic contact angle test), and chemical usage (economically and environmentally-friendly procedures), the 1.0% alum and 0.5% cationic rosin levels were selected for optimum performance. This research also showed that the combined effect of alum with cationic rosin was favorable. Moreover, the sequence of alum and cationic rosin addition, which is a challenge in paper mills, also should be considered. The results indicated that the addition of cationic rosin after alum obtained the best mechanical and wet resistance results. In addition, the results showed that both acidic and neutral pH were acceptable in this sizing process.

Application of a bio-derivative, rosin, as a binder additive for lithium titanium oxide electrodes in lithium-ion batteries

Rosin, which is an extract of pine trees, is used as an eco-friendly binder additive to a conventional solvent-based binder, polyvinylidene fluoride (PVdF). The composite binder system is used to evaluate the performance of the Li4Ti5O12 (LTO) electrodes using a range of physical and electrochemical characterization techniques. The addition of rosin decreases the crystallinity of PVdF, disperses the conducting agent and binder well, and ultimately leads to an increase in the diffusivity and cyclic capacity of lithium ions. When the amount of rosin additive to the PVdF binder is 40 wt%, the LTO electrode exhibits the highest cyclic capacity and diffusivity; of 164 mAh g−1 at the 110th cycle and 4.28 × 10−10 cm2 s−1, respectively.

New Polyurethane Sealants Containing Rosin for Non-Invasive Disc Regeneration Surgery

Different polyurethane sealants were prepared by reacting methylene dyísocyanate and polyadipate of 1,4 butane diol (Mw : 2500 daltons) by using the prepolymer method and different mixtures of rosin and 1,4 butane diol were used as chain extenders. The polyurethanes were characterized by plate-plate rheology, molecular weight distribution, Differential Scanning Calorimetry (DSC), and Laser Confocal Microscopy. The tack of the polyurethanes sealants was obtained by using a modified probe tack method, and their adhesion was obtained by T-peel test of leather/polyurethane sealant/leather joints and by single lap-shear tests of aluminium/polyurethane sealant/aluminium joints. Depending on the rosin content in the chain extender the structure of the polyurethanes was different, i.e. more urethane and urethane-amide hard segments were created up to 50 eq% rosin in the chain extender, and separation of domains was prevailing in the polyurethanes with higher rosin content. Furthermore, the addition of rosin caused an increase in the length of the polymer chains and in the storage modulus (particularly in the polyurethane containing 50 eq% rosin), and decrease in the melting enthalpy. Moreover, the crystallinity of the polyurethanes containing up to 50 eq% rosin showed lower number and smaller spherulites, Finally, the tack at 37 °C and the peel strength increased in the joints made with the polyurethane sealants containing rosin whereas the adhesive shear strength decreased when the polyurethane sealant contained 50 eq% rosin or less.

Synthesis and characterization of polyurethane sealants containing rosin intended for sealing defect in annulus for disc regeneration

Thermoplastic polyurethanes containing rosin or mixtures of rosin and 1,4 butane diol in the chain extender were proposed as potential sealants for defects in disc regeneration surgery. The polyurethane sealants were prepared by using the prepolymer method and different mixtures of rosin and 1,4 butane diol were used as chain extenders. The existence of one carboxylic moiety in the rosin structure allowed the reaction with the isocyanate end groups in the prepolymer during polyurethane synthesis, creating additional urethane-amide hard segments. The polyurethanes were characterized by ATR-IR spectroscopy, differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMA), thermal gravimetric analysis (TGA), scanning electron microscopy, X-ray diffraction and laser confocal microscopy. The adhesion of the polyurethane sealants were tested by T-peel test of leather/polyurethane sealant/leather joints and by single lap-shear tests of aluminium/polyurethane sealant/aluminium joints. Depending on the rosin content in the chain extender the structure of the polyurethanes was different, i.e. more urethane and urethane-amide hard segments were created up to 50eq% rosin in the chain extender and separation of domains was prevailing in the polyurethanes with higher rosin content. Furthermore, the addition of rosin caused an increase in the length of the polymer chains but a decrease in the storage modulus was produced (particularly in the polyurethane containing 50eq% rosin), likely due to the bulky structure of the rosin as compared to the linear structure of 1,4 butane diol, allowing the separation of the linear polyurethane chains. On the other hand, the melting of the soft segments in the polyurethanes started at 40–57°C and the addition of more than 50eq% rosin in the chain extender decreased the melting enthalpy. Moreover, the crystallinity of the polyurethanes containing up to 50eq% rosin showed lower number and smaller spherulites. Finally, the peel strength increased in the joints made with the polyurethane sealants containing rosin whereas the adhesive shear strength decreased when the polyurethane sealant contained 50eq% rosin or less.

Efficient preparation of mesocarbon microbeads by pyrolysis of coal-tar pitch in the presence of rosin

Mesocarbon microbeads (MCMB) were prepared by pyrolysis of coal-tar pitch in the presence of rosin, and characteristics of the pitch-rosin mixtures and the MCMB were studied. Pyrolysis behavior of the pitch-rosin mixtures was investigated by thermogravimetric analysis (TGA), and chemical structures of the pyrolysated pitch-rosin mixtures were studied using Fourier transform infrared spectroscopy (FTIR) technique. Optical textures of the pyrolysated pitch-rosin mixtures were characterized by polarized-light microscopy. In addition, morphologies and microstructures of the MCMB, extracted from the pyrolysated pitch-rosin mixtures, were studied using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. Results show that the rosin addition contributes to a notable increase of MCMB yield as well as a decrease in the aromaticity index of the pyrolysated pitch-rosin mixtures. Moreover, the pyrolysis conditions have great effect on the morphologies and yields of MCMB. When the pitch-rosin mixtures are pyrolysated at 450 °C for 1.5–2.5 h, the MCMB yields arrive at 33.8–54.6 wt.% of the pyrolysated pitch-rosin mixtures.

Near-surface morphology effect on tack behavior of poly(styrene- b-butadiene- b-styrene) triblock copolymer/rosin films

The correlation between near-surface morphology and tack behavior of poly(styrene- b-butadiene- b-styrene) triblock copolymer (SBS)/rosin ester films was investigated using probe tack tests, transmission electron microscopy and small-angle X-ray scattering. The SBS/rosin films with rosin composition between 10 and 20 wt% rosin, prepared by slow evaporation of toluene during solvent casting, exhibited uniform near-surface morphology of lamellae oriented parallel to the surface. However, due to the limited solubility of rosin in the PS domains, the rosin started to phase-separate from the PS domains at 15 wt%, and formed fully separated micron-sized domains above 20 wt% rosin. The probe tack force of the SBS/rosin films increased steadily when the near-surface domain orientation changed from perpendicular cylinder to parallel lamellae on addition of rosin. Specifically, for a given lamellar morphology and surface orientation, macrophase separation of rosin plays a critical role in determining the tack properties of SBS/rosin films.

TiO 2 price rises posted for North American papermakers & Asia/Pacific

A study was conducted to determine a more efficient means of preparing paper resistant to liquid penetration through addition of rosin and papermakers' alum to cellulose. Paper sizing is accomplished by depositing a hydrophobic aluminum-rosin precipitate on the cellulose fibers. In order to optimize the interaction with cellulose, it is necessary that the precipitate be positively charged. It was hoped that proper control of the particle size and the electrokinetic potential of the precipitate prior to addition to the pulp would result in a more efficient sizing of the cellulose fibers. The appropriate conditions were determined under which a highly dispersed stable positively charged colloidal suspension of rosin acid in the presence of aluminum salts could be prepared. Considerable differences were observed with Al2(SO4)3 and Al(NO3)3 as a result of the presence of the divalent sulfate ion. A series of sized paper handsheets were prepared using preformed positively charged aluminum rosinate suspensions and their resistance to liquid penetration was determined. Inferior results were obtained with the preformed suspensions when compared to the normal means of in situ sizing where rosin size is added to the cellulose suspension followed by alum. Further paper handsheet trials were carried out in an attempt to determine the reasons for decreased sizing efficiency obtained with the preformed precipitate. The results are discussed in terms of the most important mechanisms involved in the sizing of paper.

Characterization of thermoplastic polyurethane adhesives with different hard/soft segment ratios containing rosin as an internal tackifier

Three thermoplastic polyurethanes (TPUs) containing different hard/soft (h/s) segment ratios (1.05-1.4) were prepared using the prepolymer method. MDI (diphenylmethane-4,4′diisocyanate) and polyadipate of 1,4-butanediol (M w = 2440) were allowed to react to produce the prepolymer. To provide the polyurethanes with high immediate adhesion to different substrates, a rosin + 1,4-butanediol mixture (1 : 1 equivalent%) was used as chain extender (TPU-Rs). These TPU-Rs had two types of hard segments: (i) Urethane hard segments, produced by reaction of the isocyanate and the 1,4-butanediol, and (ii) Urethan-amide hard segments, produced by reaction of the isocyanate and the carboxylic acid functionality of the rosin. The TPUs and TPU-Rs were characterized using FTIR spectroscopy, gel permeation chromatography, differential scanning calorimetry, stress-controlled plate-plate rheology, stress-strain measurements, and Brookfield viscosity. The TPUs and TPU-Rs were used as raw materials to prepare solvent-based polyurethane adhesives, the adhesion properties of which were obtained from T-peel tests on PVC/polyurethane adhesive/PVC joints. The addition of rosin as an internal tackifier increased the average molecular weight, more markedly in the TPU-Rs containing higher hard/soft segment ratios, but the elastic and viscous moduli decreased. An increase in the hard/soft segment ratio of the TPU-Rs retarded the kinetics of crystallization (which was determined by the soft segment content in the polyurethane), and increased the immediate T-peel strength in PVC/polyurethane adhesive/PVC joints (which was determined by the urethan-amide hard segments). Furthermore, addition of rosin to the polyurethanes decreased the final adhesion, although always reasonably high peel strength values were obtained.

Lead free solder alloys Sn-Zn and Sn-Sb prepared by mechanical alloying

The mechanical alloying (MA) processes of tin-9zinc (Sn-9Zn) and tin-5antimony (Sn-5Sb) were analyzed using an X-ray diffractometer, a differential scanning calorimeter (DSC) and a scanning electron microscope (SEM). The results showed that supersaturated solid solution and intermetallic compound were produced during the MA process. The size of powder particles could be controlled under the proper MA conditions and was reduced to 5 to 20 μm. As a surfactant, proper addition of rosin allows MA to occur smoothly. However, it may also be a source of contamination of the metallic powder. It is considered that MA may be a technique analogous to casting to prepare solder alloys.

Internal Treatment of Paper Sheets from Wood and Bagasse Pulps with Polyvinyl Alcohol

Mechanical strength and optical properties of paper sheets prepared from polyvinyl alcohol (PVA)-treated wood and bagasse pulps were investigated. The effects of the percentage of added PVA, the amount and type of polymer precipitant, and the manner of polymer addition (before or after the beating stage) on the properties of prepared sheets were presented. Studies were also carried out to compare the properties of loaded paper sheets produced from PVA-treated pulp and fillers (kaolin, TiO2, talc, and CaCO3), with those produced from conventional rosin-alum-filler loaded paper sheets. The obtained results show that 4% PVA (based on pulp) and 100% borax (based on polymer) were the optimum additives required to attain the maximum improvement in the strength properties of the paper sheets obtained from both pulps. It was found that the pH value of the pulp slurry has a profound effect on the filler retention and strength properties of produced sheets, whereas it has a weak effect on the optical properties of sheets. The optimum strength properties were noticed at pH 7.0. Also, the addition of PVA was more efficient for improving the strength and optical properties of paper sheets loaded with a high percentage of Filler, especially kaolin, compared with conventional rosin-alum addition. However, the reverse trend was noticed in the case of the oil resistance property for ail paper samples under investigation, except the case of paper sheets made from 4% PVA addition to bagasse pulp, as the beating additive, whereas its oil resistance property was nearly the same as the case of rosin addition.

Effect of rosin addition and thermal treatment on rice straw hardboard

AbstractAddition of rosin to rice straw pulp decreased the strength properties of the finished product, while it improved its water resistance. The effect of rosin addition was lower in the presence of phenol formaldehyde resin.

The effect of pH of rosin on setting time of root canal cements

Most root canal cements contain rosin, as well as zinc oxide, in their powder component. The purpose of rosin is to impart adhesiveness to the cement. It was found that the rosins used in dentistry have a wide variation in pH, ranging from 4.5 to 7.9. In this study, rosins having a pH of 6.2 or lower accelerated the setting time of cements; whereas, those having a pH of 7 or higher retarded or interferred with the setting of the cements. Zinc oxide-eugenol cement without rosin did not set hard in 24 hours and was friable when it did set. The addition of rosin to zinc-oxide powder gave it body, coherence, and allowed it to set in a reasonable time. Most root canal cements contain rosin, as well as zinc oxide, in their powder component. The purpose of rosin is to impart adhesiveness to the cement. It was found that the rosins used in dentistry have a wide variation in pH, ranging from 4.5 to 7.9. In this study, rosins having a pH of 6.2 or lower accelerated the setting time of cements; whereas, those having a pH of 7 or higher retarded or interferred with the setting of the cements. Zinc oxide-eugenol cement without rosin did not set hard in 24 hours and was friable when it did set. The addition of rosin to zinc-oxide powder gave it body, coherence, and allowed it to set in a reasonable time.

The formation of positively charged aluminum rosinate precipitates and their effect on paper sizing efficiency

A study was conducted to determine a more efficient means of preparing paper resistant to liquid penetration through addition of rosin and papermakers' alum to cellulose. Paper sizing is accomplished by depositing a hydrophobic aluminum-rosin precipitate on the cellulose fibers. In order to optimize the interaction with cellulose, it is necessary that the precipitate be positively charged. It was hoped that proper control of the particle size and the electrokinetic potential of the precipitate prior to addition to the pulp would result in a more efficient sizing of the cellulose fibers. The appropriate conditions were determined under which a highly dispersed stable positively charged colloidal suspension of rosin acid in the presence of aluminum salts could be prepared. Considerable differences were observed with Al 2(SO 4) 3 and Al(NO 3) 3 as a result of the presence of the divalent sulfate ion. A series of sized paper handsheets were prepared using preformed positively charged aluminum rosinate suspensions and their resistance to liquid penetration was determined. Inferior results were obtained with the preformed suspensions when compared to the normal means of in situ sizing where rosin size is added to the cellulose suspension followed by alum. Further paper handsheet trials were carried out in an attempt to determine the reasons for decreased sizing efficiency obtained with the preformed precipitate. The results are discussed in terms of the most important mechanisms involved in the sizing of paper.