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The conventional use of polyurethane in various applications is hindered by significant challenges, such as toxicity concerns, moisture sensitivity, and environmental impact. In response, there has been a notable surge in research focusing on bio-based alternatives, particularly non-isocyanate polyurethanes (NIPUs), aligning with sustainable development objectives. NIPUs offer a promising solution by eliminating the need for isocyanates, employing cyclic carbonates and diamines instead. Out of various sources available, non-traditional vegetable oils present a viable starting material for cyclic carbonate synthesis due to their availability, renewability, and affordability. However, despite the growing interest in NIPUs, there remains a scarcity of literature on the utilization of non-traditional oils for their development. This short review aims to fill this gap by providing an overview of bio-based NIPUs synthesized from non-traditional vegetable oils such as jatropha oil, castor oil, lignin oil, linseed oil, and rubber seed oil. The review covers the synthesis methods of NIPUs via polyaddition reactions of carbonates and amines, detailing properties, advantages, and applications of each oil-based NIPU. Furthermore, by identifying research gaps and proposing potential solutions, this paper aims to encourage researchers to consider non-traditional oils for NIPU synthesis, facilitating significant advancements in the field. [ABSTRACT FROM AUTHOR]

In this study, synthesis, characterization and photopolymerization of new type of castor oil-based monomer family are studied. Electrical properties of the synthesized polymers are also evaluated. The synthesis of these materials consists of two steps. Acrylation of the castor oil and methyl ricinoleate occur in the first step and epoxidation is then followed. Epoxidized acrylated castor oil (EACO) and epoxidized acrylated methyl ricinoleate (EAMR) are synthesized at the end of the reactions. FTIR (Fourier transform infrared) and 1H NMR (nuclear magnetic resonance) spectroscopy techniques are used to characterize of the starting materials and monomers. When acrylate groups are introduced to castor oil and methyl ricinoleate, a characteristic peak at 1722 cm−1 is observed in FTIR spectrum and peaks of acrylate hydrogens at 5.7, 6.0 and 6.3 are observed in 1H NMR spectrum. After epoxidation, a small peak is detected at 840 cm−1 in FTIR spectrum and new peaks appear at 2.5 and 3.0 ppm in 1H NMR spectrum. Photopolymerization of the synthesized materials are performed with DMPA (2,2-dimethoxy-2-phenylacetophenone) and AIBN (azobisisobutyronitrile) catalyst. It is found that DMPA catalyst is more effective than AIBN. EACO samples' DC (direct current) resistance and conductance values are measured as 146.4 MΩm and 6.83 nS/m, respectively, whereas EAMR samples' DC resistance and conductance values are calculated as 96 MΩm and 10.42 nS/m, respectively. AC (alternative current) analysis is conducted by using LCR meter for the polymeric samples where EACO samples' capacitances varies from 4.88 to 3.29 pF (picofarads) with respect to frequency (10 Hz–300 kHZ). On the other hand, EAMR samples' capacitances varies from 14.7 to 6.49 pF with respect to frequency. Impedance values of the EACO samples with respect to frequency are measured as 4.24 GΩ and 165 kΩ, respectively. Impedance values of the EAMR samples with respect to frequency are measured as 1.19 GΩ and 82 kΩ, respectively. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing demand for environmentally friendly epoxides made from vegetable oils, including castor oil. This study aims to produce epoxidized castor oil derived ricinoleic acid (ECORA) with applied synergistic sulfate-impregnated zeolite ZM-5 as catalyst. To date, there is no published work on production of ECORA by peracetic acids mechanism using hybrid homogenous–heterogenous catalyst. Peracetic acid produced in situ was used to produce ECORA. By combining acetic acid, which acts as an oxygen carrier, with hydrogen peroxide, which acts as an oxygen donor, peracetic acid was formed. The ratio of ricinoleic acid to acetic acid was used at a ratio of 1:1, while a 1:1 molar ratio of hydrogen peroxide to castor oil was introduced. The epoxidation process has been conducted at a temperature of 55 °C. The mixture was then stirred continuously at a fixed speed of 200 rpm. The maximum conversion to oxirane was achieved at 58%. Overall, ECORA was successfully produced via in situ epoxidation of castor oil with applied hybrid catalyst. [ABSTRACT FROM AUTHOR]

In this work, composites were prepared in polyurethane (PU) matrices with sawdust fibers at levels of 10, 20 and 30%. The PU was obtained using polyols, castor oil and wood tar pitch (bio-pitch), reacted with a polymeric 4,4′-diphenylmethane diisocyanate (MDI), in a ratio NCO/OH = 1:1, catalyzed by dibutyltin dilaurate. Two groups of composites were formulated: materials synthesized only with polyol castor oil (PU 0%), and those obtained with 25% bio-pitch and 75% castor oil (PU 25%). The sawdust fibers were previously modified by mercerization, followed by benzylation or reaction with toluene diisocyanate (TDI). The changes were confirmed by infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetry (TG), X-ray diffraction and X-ray photoelectron spectroscopy (XPS). The addition of bio-pitch to the matrix caused an increase in its porosity and a decrease in density. The sawdust showed good adhesion to the matrix containing bio-pitch, which was confirmed by the increase in the mechanical properties of its composites. The water absorption results showed that the matrix composites containing bio-pitch are more hydrophobic, with greater intercrossing, which corroborates the evaluation of good fiber–matrix interaction. Vegetable pitch seems to behave as a coupling agent between the fiber and the matrix, presenting itself as a suitable polyol for the synthesis of composites from renewable sources. [ABSTRACT FROM AUTHOR]

Urethanization of castor oil (CO), β-cyclodextrin (CD), and 1-adamantanol (AdOH) with hexamethylene diisocyanate (HDI) at a CD/AdOH molar ratio of 1:1 and various feed CO fractions produced castor oil-based polyurethane network films (CAPUs) incorporating cyclodextrin and adamantane units as host and guest components, respectively. For comparison, similar urethanization reactions were performed with CO/CD/HDI and CO/AdOH/HDI to produce network films that lacked guest or host moieties (CDPU and ADPU, respectively). The results of Fourier transform infrared spectroscopy and gel fraction measurements confirmed the formation of polyurethane networks. The glass transition temperatures, tensile strengths, and tensile moduli of the network films increased with decreasing CO fractions. All CAPU films demonstrated healing properties at room temperature; however, the CDPU and ADPU films did not. The healing efficiency also increased with decreasing CO fraction. [ABSTRACT FROM AUTHOR]

This work focuses on the improvement of the electrospinnability of low-sulfonate lignin (LSL)/polyvinylpyrrolidone (PVP) solutions by the addition of surfactants (SDS, CTAB and Tween-20) as well as on the ability of resulting nanofibers to structure castor oil. Solutions with two LSL/PVP weight ratios (70:30 and 90:10) in DMF were prepared by adding variable surfactant concentrations (0–1 wt.%), and physicochemically characterized. Electrical conductivity, surface tension and rheological measurements were performed. Variations of these physicochemical properties were explained on the basis of surfactant-polymer interactions. The addition of surfactants to LSL/PVP solutions improves electrospinnability, producing more compact and uniform fiber mats in 70:30 LSL/PVP systems, generally reducing the average diameter of the nanofibers and the number of beads. In contrast, nanofiber mats were not obtained with 90:10 LSL/PVP solutions, but different nanostructures composed of particle clusters. Dispersions of nanofiber mats obtained by electrospinning from 70:30 LSL/PVP solutions in castor oil were able to generate physically stable strong oleogels. In general, linear viscoelastic functions of oleogels increased with surfactant concentration. In addition, these oleogels exhibited excellent lubrication performance in a tribological contact, with extremely low values of the friction coefficient and wear diameters, which may lead to potential applications as lubricants. [ABSTRACT FROM AUTHOR]

A series of lignin-based biological waterborne polyurethanes (LBWPU) with excellent properties were synthesized by prepolymerization with different contents of sodium lignosulfonate aqueous solution (NaLS) as dispersant. Biological isocyanate (1, 5-pentamethylene diisocyanate), biological polyether polyol (H-2000) and castor oil were used as the main reaction materials to prepare waterborne polyurethane with biological content up to 70%, which had excellent storage stability. The effects of different contents of NaLS on the thermo-mechanical properties, mechanical properties and thermal stability of polyurethane films were studied. With the increase in NaLS content, the mechanical properties, storage modulus and water resistance of LBWPU films were significantly enhanced. Meanwhile, the limiting oxygen index of the prepared LBWPU could reach 24.7% after blending with the flame retardant, showing good flame retardancy. In this work, the water-based polyurethane materials with high bio-base content could be used as a film-forming agent in the field of leather finishing agent, which has an important influence on improving the flame retardant of leather. [ABSTRACT FROM AUTHOR]

This study involves the development of sustainable technology/methodology for the production, characterization and numerical calculation of highly effective multi-component anti-hail seeding reagents (seeding composites) based on silver iodide and iodide of an alkali metal, homogenized in synthetic or bio polyurethane binder. Polyurethane-based seeding composites are produced via casting method and the results of uniaxial tensile tests, hardness and dynamic-mechanical analysis show that applied technique is more suitable compared to the conventional dry homogenization of the seeding active agents. Lower viscosity, uniform powdered seeding agents distribution and improved mechanical properties, e.g. higher tensile strength (5.05 MPa) and Shore A hardness (89 ShA) are achieved using castor oil as bio-polymer binder, compared to the synthetic polymer hydroxyl terminated poly(butadiene). In addition, significantly higher glass transition temperature obtained for seeding composite with castor oil as polymer binder indicating higher density and branched polymer network. Numerical models of the convective clouds are used to determine composition and mass of seeding agent which gives the best results concerning hail suppression or rain intensification. Results show that composite seeding reagents which contain silver iodide and potassium iodide in a molar ratio of 1:2 upon combustion generate freezing nuclei which are active above 0 °C, providing the most effective cloud seeding with 10.53% hail accumulations suppression. [ABSTRACT FROM AUTHOR]

Plastic waste has become a pervasive and global threat to every ecosystem, and the continuous surge in plastic production has triggered the need for sustainable alternatives. This study focuses on harnessing a hundred percent biodegradable composite sheets with a natural crosslinker, which can be used in several end applications like seedling trays, gardening pots, sampling trays, one-time plates, ear and nasal swabs, etc. The proposed composite is manufactured with all-natural ingredients and zero harmful chemicals. The waste Kibisu silk or filature silk fibre (Bombyx mori) is used here as the fibre reinforcement, and wheat gluten (WG) is used as the matrix material. For plasticising and crosslinking the WG, castor oil and fresh lemon extract (Citrus limon) are used. In addition, pellets of sodium hydroxide are also added as a dispersion agent for WG. All the significant constituents used here are industrial waste or abundantly available in nature. The properties obtained from the characterisation processes indicate that natural crosslinker adds better physio-chemical properties in the developed samples. [ABSTRACT FROM AUTHOR]

Castor oil was autoxidized for three months to obtain macroperoxide castor oil (PCO). Since this polymeric oil has peroxide groups and hydroxyl groups, free-radical polymerization (FRP), ring-opening polymerization, and one-pot polymerization both free-radical polymerization (FRP) and ring-opening polymerization in one step methods were used to synthesis of various types of the graft copolymers. PCO-g-Polystyrene, PCO-g-Poly(methyl acrylate), and PCO-g-Poly(tert-buytl acrylate) were synthesized using the free-radical polymerization method. PCO-g-Poly(ε-caprolactone) graft copolymer was obtained via ring-opening polymerization, and PCO-g-Polystyrene-g-Poly(ε-caprolactone) graft copolymer was obtained using one-pot polymerization method. All graft copolymers obtained were characterized by proton nuclear magnetic resonance (1H NMR), Fourier-transform infrared, differential scanning calorimetry, thermal gravimetric analysis, and elemental analysis. After the synthesis of castor oil-based copolymers, we determined the antimicrobial effects of them as well as the antiproliferative effects on breast cancer cell lines. Antimicrobial activity was carried out using the disc diffusion method and the dilution method. As a result of antimicrobial activity, the compounds showed moderate antimicrobial effects on microorganisms compared to standard antibiotics. In particular, the compounds have shown more antibacterial activity than antifungal activity. We also observed a prominent antiproliferative effect of synthesized compounds depending on increasing doses (1–25 µg/mL) and times (24–48 h) in MDA-MB-231 breast cancer cells. [ABSTRACT FROM AUTHOR]

Castor oil (CO) as an inexpensive green polyol possesses antimicrobial and anti-inflammatory and wound healing properties. The castor oil/nanohydroxyapatite (nHA) modified chitosan (CS) composite (CO/nHA-CS) with 1. 2.5, 5, and 7.5 wt% of nHA-CS were synthesized via solution mixing and casting technique. The crystal structure, surface functional group, thermal stability, morphology, water absorption capacity, porosity, biodegradability, antibacterial activity, and cytocompatibility properties of CO/nHA-CS bionanocomposites have been evaluated. FESEM images showed random and uniform dispersion of nHA-CS fillers throughout the cured CO resin. The degree of porosity, water absorption, and biodegradability of the nanocomposites increased with the increase in nHA-CS loading. Antibacterial activity of scaffolds against Escherichia coli and Staphylococcus aureus bacteria was identified by the diffusion method. The scaffolds were more effective against the growth of Staphylococcus aureus than Escherichia coli. Cell viability results confirmed that CO/nHA-CS composites have no toxic effects against MRC-5 fibroblast cells. In conclusion, CO/nHA-CS has the potential to be explored as a cheap and effective wound healing material. [ABSTRACT FROM AUTHOR]

The aim of this study was to synthesize organo-hydrogels, by using agar, glycerol and different amounts of castor oil in one step, with biocompatible, blood-compatible and antioxidant properties using a new approach to the synthesis of smart polymers. Then, the target was to investigate the applicability of these organo-hydrogels as a drug release system. In the synthesis of organo-hydrogels, crosslinking was achieved with MBA or GA reagent and the redox polymerization technique was applied in the emulsion medium. The swelling behaviors of organo-hydrogels, which were synthesized using different crosslinkers and varying amounts of castor oil, were investigated in different solvent systems (ethanol, acetone, ethanol/DI water (1:1), acetone/DI water (1:1) and gasoline) and in different pH (2.0–12) media. In addition, FTIR, antioxidant, blood clotting and hemolysis analyses were evaluated in light of the results obtained. In the last stage of the study, drug-loaded organo-hydrogels were synthesized by the direct drug loading method and used as a drug delivery vehicle. Vitamin D3, which is of great importance in the human body and used as an antibiotic, was selected as a model drug. Release studies were carried out in different pH media because various areas of the human body were the main targets in this study and the plan was to provide controlled release of the drug substance in these regions. The pH values of these regions were important in terms of application. Therefore, pH (2.0–12) values for various parts of the human body were imitated in the laboratory environment and release behaviors were examined in experimental studies. It can be said that the synthesized organo-hydrogels were suitable for use as drug transport systems in light of the obtained results. [ABSTRACT FROM AUTHOR]

Present study focuses on the development of sustainable green-sourced carbon nano-sphere (CNSp) from Betel Leaf by thermal decomposition method for high-performance Polyurethane coating. The obtained carbon black was then functionalized with acid solution. FTIR analysis confirms the presence of carboxyl group. The graphitic domain present in the nano-sphere were found using XRD and Raman spectroscopy. TEM analysis clearly shows the mono-dispersed sized nano-spheres of about ~ 40 nm. The nano-sphere was further incorporated into castor oil based Polyurethane coatings. The nanoscale incorporation of the CNSp (0.2 and 0.5%) into the PU shows good increment in the resultant mechanical and thermo-mechanical properties of the polyurethane/carbon nano-sphere hybrid in comparison to the virgin PU film. The DMTA result shows an increase in the storage modulus from 3730 to 4454 MPa. Moreover, an accretion in the tensile strength was observed from 5.55 to 9.77 MPa Overall increments of 76.03% and good surface roughness observed by SEM analysis. [ABSTRACT FROM AUTHOR]

Surfaces of nano-hydroxyapatite (n-HA) particles were modified by grafting of etidronic acid (ETD, 0.1 M) and were reinforced into polyurethane scaffolds prepared by foaming method to develop porous modified nano-hydroxyapatite/polyurethane (m-HA/PU) nanocomposite scaffolds for bone tissue engineering. Particle size and morphology of nanoparticles were studied using X-ray diffraction, transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. TEM and SEM results revealed that the surface of obtained modified hydroxyapatite (m-HA) particles was completely changed from grain- to plate-type structure with the size of 40 nm. Chemical structure, mechanical properties and biomedical application were studied using Fourier transform infrared spectroscopy (FTIR), universal testing machine and in vitro studies. In FTIR spectra, disappearance of peak around 2270 cm−1 confirmed the formation of polyurethane nanocomposite scaffolds and bands in the spectral range of 1400 and 800–900 correspond to the presence of calcium and phosphate groups due to hydroxyapatite. As the concentration of m-HA increased from 0 to 30 wt%, the compressive strength of the resulting PU/m-HA nanocomposites increased from 0.094 to 22.4 MPa. In vitro study with simulated body fluid (SBF) for 4 weeks indicated that surface was partially hydrolysed. Cell culture study showed that m-HA/PU nanocomposite scaffold is well suited for application in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Intrinsic cross-linked waterborne polyurethane (CWPU) was successfully synthesized for the first time through solvent-free condensation polymerization, in which green castor oil (CO) was used as the cross-linking agent. The totally solvent-free process was realized by using hydrophilic polypropylene glycol as hydrophilic segment, which was synthesized by the esterification of polypropylene glycol with pyromellitic dianhydride. The effect of CO content in the soft segment of the prepared CWPU on emulsion properties was investigated by laser particle size distribution test, and the prepared CWPU emulsion showed uniform size distribution (0.117–0.275 µm) and milky white appearance after storing at ambient temperature for 6 month. Additionally, the effect of CO content in CWPU films on static mechanical properties, dynamic mechanical properties, hydrophilicity and thermal stability was also studied by tensile test, dynamic mechanical analysis, water absorption and contact angle measurement as well as thermogravimetric analysis. The prepared cross-linked CWPU films have good stability and outstanding mechanical strength (11.94–34.51 MPa), making them adequate supplement for the conventional waterborne polyurethanes. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate and compare the effects of two different types of polyols on properties of synthesized polyurethanes (PUs), to develop biomedical applications of these materials. Polyurethane membranes were prepared from two different polyols (castor oil and CAPA 7201) as wound healing films. The chemical, physical, mechanical and biological properties of the prepared membranes were studied. Both films had smooth surfaces, with no signs of pores and cracks. CAPA-based polyurethane showed higher crystallinity and lower thermal stability compared to the other polyurethanes. Results of contact angle and water vapor transmission rate (WVTR) showed no significant differences between two different polyols used in PU synthesis. The water absorption of the CAPA-based PU (5.67%) was higher than the castor oil-based PU (0.76%) after immersion in water for 3 days at 37 °C. The values of WVTR were obtained as 260 and 285 g/m2/day for PCL and castor oil-based PUs, respectively. CAPA-based PU membrane showed 4 MPa tensile strength and about 550% elongation at break which is higher than the other samples (1.7 MPa and 100%). The viability of L-929 mouse cell line in contact with CAPA-based PU film was greater than 80% and showed a lack of toxicity of the synthesized polymer. The in vivo wound healing model evaluation using a full-thickness rat model experiment was carried out within 13 days. The wound size reduction of castor oil and CAPA-based PUs reached to 99% compared to 68% in gauze sample on the 13th day after surgery. The in vivo results revealed that PUs derived from CAPA 7201 was milder and led to less inflammatory response compared to castor oil which consequently was completely filled with new epithelium without any significant adverse reactions. Consequently, results confirmed the potential use of CAPA-based PU in biomedical field. [ABSTRACT FROM AUTHOR]

Ring-opening polymerizations of d-lactide, l-lactide and ɛ-caprolactone initiated from hydroxy groups of castor oil (CO) produced three kinds of branched oligomers (CODLAO, COLLAO and COCLO). The reactions of CODLAO, COLLAO and COCLO with hexamethylene diisocyanate (HDI) produced polyester–urethane networks (PUCO-scLAO/CLOs 100/0, 75/25, 50/50, 25/75 and 0/100) with different feed ratios of stereocomplex oligolactide (scLAO, that is a mixture of equal parts of COLLAO and CODLAO) and COCLO. Also, the similar reactions of COLLAO and COCLO with HDI produced homochiral networks (PUCO-LLAO/CLOs). X-ray diffraction and differential scanning calorimetry analyses revealed that stereocomplex crystallites were exclusively formed for all of the PUCO-scLAO/CLOs except for the 0/100 sample, whereas the oligo(l-lactide) segments of PUCO-LLAO/CLOs 100/0 and 75/25 did not homo-crystallize. Scanning electron microscopic analysis revealed that the compatibility for the PUCO-scLAO/CLO and PUCO-LLAO/CLO 75/25–25/75 conetworks slightly decreased with increasing CLO fraction. Dynamic mechanical analysis revealed that the lowering of storage modulus due to glassy-to-rubbery transition for PUCO-scLAO/CLOs 100/0–25/75 was much smaller than that for PUCO-LLAO/CLOs 100/0–25/75. Although the incorporation of CLO segments was effective to increase the elongation at break, the tensile strengths and moduli of the 75/25–25/75 conetworks were considerably lower than those of the 100/0 and 0/100 networks. Consequently, the 100/0 and 0/100 networks exhibited more balanced tensile properties than the 75/25–25/75 conetworks. It is noteworthy that the tensile toughnesses and elongations at break of the CO-modified 100/0 networks are much higher than those of the similar networks using glycerol instead of CO. [ABSTRACT FROM AUTHOR]

The paper describes the chemical depolymerization of the polyethylene terephthalate (PET) waste from postconsumer soft drink bottles and a search for the way to use this product. The depolymerized oligoester obtained from glycolysis of PET waste using tiethylene glycol was transesterified with castor oil which resulted in the formation of hydroxyl-functional polyester polyol, with hydroxyl value of 391 mg KOH g−1. In the presented paper, series of castor oil-based waterborne polyurethane (CPU)/silica hybrid dispersions were prepared using dimethylolpropionic acid as an ionic center. The polyurethane prepolymers with pendent castor oil groups were prepared first, and then different concentrations of hydrophilic fumed silicas (0, 0.5, 0.75, 1.0 and 2.0 wt%) were added. For waterborne polyurethane dispersions of hydrophilic fumed silica with the surface area (50 ± 15 m2/g) and a primary particle size of 40 nm in the polymer matrix, ultrasound waves were used. The hybrid dispersions were prepared by adding the required amount of triethylamine and water. The molecular structures and mass of glycolyzed PET oligoesters, castor oil-based polyol and castor oil-based polyurethane-silica hybrid dispersions were estimated by FTIR method and gel permeation chromatography.The incorporation effect of SiO2 nanoparticles into the PU matrix on the thermal and mechanical properties of resulting polyurethane films has been examined by Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis, differential scanning calorimetry (DSC), SEM microscope, and measurement of the coatings properties. The DSC data results suggest that hard segment glass temperature decreases, but mixed-phase glass transition temperature increases with increasing SiO2 content. The FTIR deconvolution result of the degree of phase separation between oxide nanoparticles and hard segment supports to the DSC analysis. The addition of silica oxide caused the increase in the thermal stability. The T10% and T50% of CPU films (the temperatures where 10 and 50% weight loss occurred) increased with increasing the SiO2 content. UV-Vis spectrophotometry showed that introduction of nanosilica particles into polyurethane enhanced the shielding property of obtained films for UV light. The hardness, adhesion, and gloss quality of the polyurethane films were also determined considering the effect of the phase separation and the SiO2 content, so this paper confirmed the suitability of using these castor oil-based waterborne polyurethane/silica hybrid dispersions as new materials with high-performance coatings materials. [ABSTRACT FROM AUTHOR]

The present work deals with surface properties of chlorine containing polyurethane-urea (PU-urea)-coating films. First, isocyanate-terminated pre-polymers were synthesized using castor oil as renewable resource, isophorone diisocyanate, and different weight percentages of 2-chloroethanol and 2,2,2-trichloroethanol. The resultant isocyanate-terminated pre-polymers were cured under atmospheric moisture to obtain chlorine containing PU-urea coatings. The surface properties of the coating films were characterized using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, and X-ray diffraction. All characterization techniques suggest that the presence of chlorine species on the surface results in different surface properties when compared to control PU-urea (without the chlorine group)-coating film surface. The viscoelastic, swelling, and contact angle (CA) properties were studied for the prepared coating films. The glass-transition temperatures (Tg) were obtained in the region 29.2-35 °C for the coating films. Tg increased by increasing the chlorine content in polyurethane-coating formulations. The CA for the coating films was found to be in the range of 76°-64° and these properties were found to be decreased with increase in the weight percent content of the chlorine moiety in the final coating formulation. Similarly, the higher chlorine content-coating films have shown more water uptake properties. The overall comparative results indicate that the chlorine containing PU-urea-coating films have different surface-coating properties and these depend upon the chlorine content in the final coating formulation as compared with PU-urea surfaces. [ABSTRACT FROM AUTHOR]

The article investigates the performance of polymers prepared from castor oil and dodecyl acrylate as biodegradable multifunctional additive in the formulation of eco-friendly lubricant. Homopolymer of castor oil and its copolymers with dodecyl acrylate (DA) at different percentage ratios (w/w) were synthesized using azobisisobutyronitrile (AIBN) as initiator without any solvent. The polymers were characterized by spectral techniques (FT-IR and NMR spectroscopy). The molecular weight of all the prepared polymers was determined by gel permeation chromatography (GPC). The thermal stability of the polymers was determined by thermogravimetric analysis (TGA). Performance evaluation of all the prepared polymers in SN150 mineral oil as viscosity index improver (VII), pour point depressant (PPD) and antiwear were carried out according to standard ASTM methods. The action mechanism of the additives as PPD was studied by photo micrographic image. Biodegradability of all the samples was tested through soil burial test (SBT). [ABSTRACT FROM AUTHOR]

In the present study, the effects of architecture and structural building blocks of the polyurethane chains on their properties were studied. New linear and hyperbranched polyurethanes (LPU and HPU) were prepared via A2 + B2 and A2 + B3 methodologies, respectively. Polyethylene glycol (PEG-1000) and castor oil (CO) were used as bi- and trifunctional monomers (B2 and B3), respectively. However, A2 monomers were synthesized by the reaction between ethylene glycol (EG) with terephthaloyl chloride (TPC) and reacting the product with excess toluene diisocyanate (TDI) to produce isocyanate-terminated PU (NCO-PU). NCO-PU was reacted with PEG to synthesize LPU; however, its reaction with CO synthesized HPU. NCO-PU, LPU and HPU were characterized by FTIR, H-NMR, GPC, TEM, TGA, DSC and XRD. The prepared PUs were applied as coatings and their physical, chemical and mechanical properties were investigated. The results showed that the degree of branching of HPU was 79%. No phase separation was observed in NCO-PU as indicated by its DSC curve. However, two phases are detected in HPU and LPU that represent to the hard and soft segments. NCO-PU displayed the highest crystallinity index (CrI = 89.26%). However, the high degree of branching in HPU led to lower CrI than LPU. The lack of entanglements in HPU led to its slightly lower solution viscosity than LPU. TEM images showed spherical PU nano-particles. The surface of HPU coating showed the highest gloss which is due to its low degree of crystallinity. HPU and LPU exhibited excellent chemical resistivity. [ABSTRACT FROM AUTHOR]

Hybrid polyurethanes with double-decker silsesquioxane (DDSQ) in the main chains were synthesized using castor oil and isophorone diisocyanate (IPDI) as feedstock. Double-decker octaphenylsilsesquioxanetetraol (DDSQ) was prepared and characterized by H NMR and MALDI-TOF-MS. Meanwhile, FTIR, TGA, DSC, SEM, UV-Vis spectrophotometer, tensile test techniques and static contact angle were also carried out to investigate the structures and properties of the hybrid polyurethanes. The DDSQ-containing hybrid polyurethanes exhibited improved thermal stability in terms of thermogravimetric analysis (TGA). DSC analysis demonstrated that the hybrid polyurethanes with DDSQ displayed enhanced glass transition temperature. According to the results of SEM and UV-Vis spectrophotometer, the aggregates of DDSQ were dispersed homogeneously in the hybrid polyurethanes matrix. With the inclusion of DDSQ, the hydrophobicity of the hybrid material was significantly improved as the results of the static contact angles revealed. [ABSTRACT FROM AUTHOR]

Four polyurethane/polyamide copolymer dispersions (PUCON- co-APAS) were prepared from castor oil-based polyol (CON). Castor oil (CO) was firstly transesterified with triethanolamine at 210 °C for different time intervals: 30, 60, 90 and 120 min, to produce CON30, CON60, CON90 and CON120 polyols, respectively. The hydroxyl and acid values, density, viscosity, chemical structure analysis of the CON polyols were determined. The polyols were used to prepare PUCON30- co-APAS, PUCON60- co-APAS, PUCON90- co-APAS, and PUCON120- co-APAS copolymer dispersions in five steps using prepolymer self-emulsification solvent process. The first step is the prepolymer preparation step, in which CON was reacted with dimethylolpropionic acid and excess toluene diisocyanate to produce PUCON. The second step is the copolymerization step, in which PUCON was reacted with amino-terminated aromatic polyamide sulfone. The following processes are neutralization, chain extension and dispersion steps. The prepared copolymer dispersions were characterized using FTIR, DLS, TGA, DSC and GPC. Additionally, the physical, chemical and mechanical properties of the prepared copolymers were studied. The results showed an increase in the hydroxyl number of CON with increasing transesterification time. Stronger H-bonds and smaller particle sizes are produced using CON with higher transesterification time in the preparation of the copolymer dispersions. Graphical abstract: [ABSTRACT FROM AUTHOR]

The aim of this work was to obtain and evaluate the thermal properties of castor oil polyurethane composites reinforced with lignin and cellulose from sugarcane bagasse. Sugarcane bagasse was pretreated and then delignified; then, the cellulose and lignin were milled. To produce the polyurethane, the mass ratio between polyol (castor oil) and diisocyanate was set to 1.5:1.0. The matrix was reinforced with a range of cellulose and lignin concentrations. The cellulose and lignin obtained by this process were chemically characterized. The composites were analyzed through SEM micrographs of fractured surfaces and thermal analysis. The presence of lignin or cellulose fibers in the polyurethane matrix decreases the thermal stability compared with the neat matrix. [ABSTRACT FROM AUTHOR]

In this study, castor oil-based polyurethanes-organoclay (COPUs-Cloisite 30B) nanocomposites are synthesized by mixing polypropylene glycol polyol and dehydrated castor oil (15 %), enforced with C30B nanofillers, at different weight percentages. The physico-chemical behaviors were evaluated by Fourier transform infrared spectroscopy, Fourier scanning electron microscopy, scanning electron microscopy and X-ray diffraction. Thermal stability was found improved up to ~30 °C in the sample with 5 wt% of C30B. Tensile properties depicted an improvement of ~240 % in tensile strength and decrease of ~30 % in elongation with 5 wt% organoclay, respectively. Improved physico-chemical properties of COPUs-C30B signify the usage of COPUs-C30B in the industrial and commercial applications, i.e. coatings, adhesives and automotive applications. [ABSTRACT FROM AUTHOR]