Polyol Formation Research Articles

Metathesis of butadiene rubber for the sustainable production of polyesters and polyols

Synthetic rubbers and elastomers are used extensively in different industries today, and more than 11.8 million tons are consumed annually. Butadiene rubber (BR) is the second most important synthetic rubber, with a worldwide consumption of about 3.44 million tons annually. In response to the high demand, production, and waste of BR and other industrial rubbers, a global effort has been made to reduce elastomeric, plastic, and microplastic pollution by studying various mechanisms of polymer degradation, including thermal degradation, mechanical treatment, UV exposure, and chemical processes.This work reported the synthesis of polyesters and polyols via metathesis degradation reaction from BR using the fatty acid methyl 10-undecenoate and the fatty alcohol 10-undecen-1-ol as chain transfer agents (CTA), using mild reaction conditions and a Ru catalyst. Polyesters and polyols were successfully produced with 94-97% yield. The formation of polyol, polyester, and by-products was assessed by FT-IR, NMR, GC/MS, and TGA. The molecular weights (Mn, Mw, Mz, and PDI) before and after degradation of BR and the products obtained were characterized by GPC. Different mole ratios BR:CTA were used to control the molecular weights; the Mw obtained ranged from 395 to 3963 Da.The proposed metathesis route may contribute to the reuse and recycling of BR to obtain sustainable products with added value for the synthesis of new materials.

Preparation of high‐performance polyurethane elastomers via direct use of alcoholyzed waste PET by high molecular weight polyester diols

AbstractProducts obtained by alcoholysis of waste PET are promising raw materials for the synthesis of polyurethane elastomers (PUEs). Alcoholysis of PET by low molecular weight diols such as ethylene glycol yields low molecular weight products. The latter need to be polymerized to high molecular weight polyols which are subsequently used as soft segments for the synthesis of PUEs. This work aims to look for suitable high molecular weight diols for the alcoholysis of waste PET to yield high molecular weight products which can be directly used as soft segments for the synthesis of PUEs. This approach allows to save the polymerization step for the formation of high molecular weight polyols. Specifically, polyester diols such as polycaprolactone diol (Mn = 2000) were used for the alcoholysis of waste PET. The resulting PUEs exhibited very good mechanical properties: a tensile strength of up to 40.95 MPa, an elongation at break of up to 1219%, and a toughness of up to 237 MJ·m−3, along with good transparency and thermal stability.

In Silico Investigation of the Impact of Reaction Kinetics on the Physico-Mechanical Properties of Coconut-Oil-Based Rigid Polyurethane Foam

Conventionally, designing rigid polyurethane foams (RPUFs) with improved physico-mechanical properties from new, bio-based polyols is performed by modifying foam formulations via experimentation. However, experimental endeavors are very resource-dependent, costly, cumbersome, time-intensive, waste-producing, and present higher health risks. In this study, an RPUF formulation utilizing a coconut-oil (CO)-based polyol with improved physico-mechanical properties was approximated through a computational alternative in the lens of the gel time of the RPUF formation. In the RPUF formation of most bio-based polyols, their very fast gel times negatively impact foam robustness. The computational alternative functioned by finding a CO-based RPUF formulation with a gel time in good agreement with a formulation based on commercial petroleum-derived polyol (control). The CO-based RPUF formulation with the best-fit catalyst loading was approximated by simulating temperature profiles using a range of formulations with modified catalyst loadings iteratively. The computational approach in designing RPUF with improved properties was found to effectively negate foam collapse (with a shrinkage decrease of >60%) and enhance foam strength (with a compressive strength increase of >300%). This study presents an economically and environmentally sustainable approach to designing RPUFs by enabling minimized utilization of material sources for experimentation and analysis and minimized dependence on waste-producing methods.

Spent coffee ground oil as a valuable source of epoxides and epoxidation derivatives: Quantitation and characterization using low-field NMR

Coffee waste, commonly referred to as spent coffee grounds (SCG), is currently discarded and has a negative impact on the environment. However, SCG are rich in valuable ingredients including 15–20% oil, which has a profile comparable to the vegetable oils used in the production of epoxides, biobased polyols, and polymers. Our first objective was to evaluate the efficiency of three different methods, namely Soxhlet, pressurized fluid extraction, and supercritical CO2 (scCO2) on SCG oil extraction. Additionally, we aimed to test the potential of low-field (LF) NMR to analyze SCG oil and monitor the formation of epoxides and biobased polyols. Finally, we evaluated epoxidized SCG oil as a plasticizer for improving the properties of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) bioplastic. Overall, SCG showed a promising potential as a source of biopolymer precursors, while LF NMR can be an efficient and economic tool for oil evaluation and reaction monitoring.

Lewis Adduct-Dissociating Hydrolysis of Boratrane for Water-Triggered Dehydration of Copolymers with a Hydrophobic Moiety.

As a new example of intrinsically water-triggered phenomena, we report underwater dehydration of the statistical copolymers synthesized from triethanolamine borate (TEAB) methacrylate and styrene (St) induced by the hydrolysis of the pendant TEAB group. TEAB possesses high polarity owing to its internal Lewis adduct structure, which is lost by hydrolysis to triethanolamine (TEA) with a lower dipole moment. Therefore, the hydration of the copolymers became unfavorable through the hydrolysis of the pendant TEAB to TEA, despite polyol formation, and through a hydrophobic interaction based on St moieties becoming alternatively dominant. The dehydration behavior of the copolymers, along with the hydrolysis of the pendant TEAB group, was systematically investigated. The water solubility of the copolymers was found to be dependent on the gradient of the hydrolysis equilibrium of TEAB on the side chains and was the lowest for the TEA state. These findings offer a novel concept toward designing water-responsive materials.

Pre-Treatment of Used Cooking Oil Followed by Transesterification Reaction in the Production of Used Cooking Oil-Based Polyol

Used cooking oil has been considered as an economical and sustainable material that can be used widely as a starting material in the production of polymer precursors such as polyol for polyurethane. Since the composition of fatty acids and glyceride in the structure of used cooking oil remain the same as virgin vegetable oil, used cooking oil can be synthesized using the same method. However, there are certain physicochemical modifications to the oil properties that arise during the process of oil fryings such as increases in viscosity, acid value, and color changes that will affect the conversion of used cooking oil into bio-based polyol. Thus, various pretreatment methods that can be applied to used cooking oil such as adsorption, chemical bleaching, and treatment with solvents will be reviewed in this paper. Transesterification of used cooking oil with alcohol in the presence of catalyst will produce used cooking oil-based polyol which will have two or more hydroxyl groups per molecule. The formation of polyol can be confirmed with the formation of O-H peak in the FTIR spectrum during the FTIR spectroscopy analysis. This paper will also discuss the type of alcohol and catalyst used in the transesterification reaction. Used cooking oil-based polyol obtained from transesterification reaction has been reported to be comparable to the commercial polyol.

Plasma Oxygen Interaction with Organic Polymer Films: A Mechanistic Study

In this presentation, first principles calculations combined with advanced surface diagnostics are used to unravel the mechanisms of plasma oxygen interaction with organic films, of interest for advanced patterning in semiconductor device manufacturing. Results from a combination of X-ray photoelectron spectroscopy (XPS) diagnosed oxygen plasma-exposed polystyrene films and first principles modeling of organic films (polystyrene, polyethylene and derivatives) provide insights into how organic films are oxidized by oxygen atoms. XPS measurements show the rapid formation of C-O structures and their saturation after oxygen exposure on both pristine and argon bombarded polystyrene samples. Quantum mechanics calculations confirm that C-OH formation can be immediate without recourse to previously formed dangling bonds. Multiple oxygen impacts are required for scission of pristine ethylene carbon strands. Therefore, ethylene films can be converted to polyols that are stable, whereas more likely strands are broken before polyol formation through the formation of water and C=O. On the contrary, intermediate compounds with adjacent C=O bonds are not likely to form stable structures. The combination of XPS measurements and modeling imply that the oxidation of polystyrene and polyethylene is self-limiting on both hydrogen saturated and de-hydrogenated (after argon ion plasma bombardment) surfaces.

Complex Organic Matter Synthesis on Siloxyl Radicals in the Presence of CO.

Heterogeneous phase astrochemistry plays an important role in the synthesis of complex organic matter (COM) as found on comets and rocky body surfaces like asteroids, planetoids, moons and planets. The proposed catalytic model is based on two assumptions: (a) siliceous rocks in both crystalline or amorphous states show surface-exposed defective centers such as siloxyl (Si-O•) radicals; (b) the second phase is represented by gas phase CO molecules, an abundant C1 building block found in space. By means of quantum chemistry; (DFT, PW6B95/def2-TZVPP); the surface of a siliceous rock in presence of CO is modeled by a simple POSS (polyhedral silsesquioxane) where a siloxyl (Si-O•) radical is present. Four CO molecules have been consecutively added to the Si-O• radical and to the nascent polymeric CO (pCO) chain. The first CO insertion shows no activation free energy with ΔG200K = −21.7 kcal/mol forming the SiO-CO• radical. The second and third CO insertions show Δ ≤ 10.5 kcal/mol. Ring closure of the SiO-CO-CO• (oxalic anhydride) moiety as well as of the SiO-CO-CO-CO• system (di-cheto form of oxetane) are thermodynamically disfavored. The last CO insertion shows no free energy of activation resulting in the stable five member pCO ring, precursor to 1,4-epoxy-1,2,3-butanone. Hydrogenation reactions of the pCO have been considered on the SiO oxygen or on the carbons and oxygens of the pCO chains. The formation of the reactive aldehyde SiO-CHO on the siliceous surface is possible. In principle, the complete hydrogenation of the (CO)1−4 series results in the formation of methanol and polyols. Furthermore, all the SiO-pCO intermediates and the lactone 1,4-epoxy-1,2,3-butanone product in its radical form can be important building blocks in further polymerization reactions and/or open ring reactions with H (aldehydes, polyols) or CN (chetonitriles), resulting in highly reactive multi-functional compounds contributing to COM synthesis.

Repression of Polyol Pathway Activity by Hemidesmus indicus var. pubescens R.Br. Linn Root Extract, an Aldose Reductase Inhibitor: An In Silico and Ex Vivo Study

Development of diabetic cataract is mainly associated with the accumulation of sorbitol via the polyol pathway through the action of Aldose reductase (AR). Hence, AR inhibitors are considered as potential agents in the management of diabetic cataract. This study explored the AR inhibition potential of Hemidesmus indicus var. pubescens root extract by in silico and ex vivo methods. Molecular docking studies (Auto Dock tool) between β-sitosterol, hemidesminine, hemidesmin-1, hemidesmin-2, and AR showed that β-sitosterol (− 10.2 kcal/mol) and hemidesmin-2 (− 8.07 kcal/mol) had the strongest affinity to AR enzyme. Ex vivo studies were performed by incubating isolated goat lenses in artificial aqueous humor using galactose (55 mM) as cataract inducing agent at room temperature (pH 7.8) for 72 h. After treatment with Vitamin E acetate − 100 µg/mL (standard) and test extract (500 and 1000 µg/mL) separately, the estimation of biochemical markers showed inhibition of lens AR activity and decreased sorbitol levels. Additionally, extract also normalized the levels of antioxidant markers like SOD, CAT, GSH. Our results showed evidence that H. indicus var. pubescens root was able to prevent cataract by prevention of opacification and formation of polyols that underlines its potential as a possible therapeutic agent against diabetic complications.Graphic

Soybean Oil-based Polyol as a Modified Natural Binder for Polyurethane Turf-adhesive

Polyurethane turf adhesive is a two-component system formed by reacting diisocyante and petroleum-based polyether polyol. This polyol can be replaced by soybean oil as one of the main economical and common oils. In this article, soybean oil was epoxidized followed by oxirane ring-opening in the presence of methyl alcohol and orthophosphoric acid as a catalyst in order to create hydroxyl groups in the soybean oil which are responsible for reaction with the diisocyanate molecules. The epoxidation step was confirmed by ATR-FTIR spectroscopy and iodine value measurements. Iodine value was decreased from 135.6 g/100 g of neat soybean oil to be 5.98 g/100 g of epoxidized soybean oil. In addition, the effect of orthophosphoric acid contents (0.6%, 0.8%, 1.0%, 1.2%) on the ring-opening steps was investigated, considering the same reaction time, the same alcohol concentration and constant temperature. Successful oxirane ring-opening was confirmed by oxirane oxygen content (OOC) values which were decreased from 6.72% to 2.93%, 1.45%, 0.60% & 0.04% respectively. Hydroxyl value of oil-based polyols (OHV) were increased from 131, 180, 208 & 229 mg KOH/g respectively. Meanwhile, ATR-FTIR showed disappearance of the oxirane rings and appearance of hydroxyl groups as indication of polyol formation in the four samples. The four polyol samples were applied as modified natural binders in polyurethane turf adhesive formulations and showed comparable results against the standard and commercially used product SubFix 411.

Co(III)/Alkali-Metal(I) Heterodinuclear Catalysts for the Ring-Opening Copolymerization of CO2 and Propylene Oxide.

The ring-opening copolymerization of carbon dioxide and propene oxide is a useful means to valorize waste into commercially attractive poly(propylene carbonate) (PPC) polyols. The reaction is limited by low catalytic activities, poor tolerance to a large excess of chain transfer agent, and tendency to form byproducts. Here, a series of new catalysts are reported that comprise heterodinuclear Co(III)/M(I) macrocyclic complexes (where M(I) = Group 1 metal). These catalysts show highly efficient production of PPC polyols, outstanding yields (turnover numbers), quantitative carbon dioxide uptake (>99%), and high selectivity for polyol formation (>95%). The most active, a Co(III)/K(I) complex, shows a turnover frequency of 800 h–1 at low catalyst loading (0.025 mol %, 70 °C, 30 bar CO2). The copolymerizations are well controlled and produce hydroxyl telechelic PPC with predictable molar masses and narrow dispersity (Đ < 1.15). The polymerization kinetics show a second order rate law, first order in both propylene oxide and catalyst concentrations, and zeroth order in CO2 pressure. An Eyring analysis, examining the effect of temperature on the propagation rate coefficient (kp), reveals the transition state barrier for polycarbonate formation: ΔG‡ = +92.6 ± 2.5 kJ mol–1. The Co(III)/K(I) catalyst is also highly active and selective in copolymerizations of other epoxides with carbon dioxide.

Detection of glyceraldehyde and glycerol in VUV processed interstellar ice analogues containing formaldehyde: a general formation route for sugars and polyols

ABSTRACT Complex organic molecules (COMs) have been identified toward high- and low-mass protostars as well as molecular clouds. Among them, sugar-like and polyol two carbon-bearing molecules such as glycolaldehyde (GA) and ethylene glycol (EG) are of special interest. Recent laboratory experiments have shown that they can efficiently be formed via atom addition reactions between accreting H-atoms and CO molecules or via energetic processes (UV, electrons) on ice analogues containing methanol or formaldehyde. In this study, we report new laboratory experiments on the low-temperature solid state formation of complex organic molecules – the first sugar glyceraldehyde and its saturated derivative glycerol – through VUV photolysis performed at three different temperatures (15, 50, and 90 K) of astrochemically relevant ices composed of water and formaldehyde. We get evidence that the species production depends on the ice temperature during photolysis. The results presented here indicate that a general scheme of aldose and polyol formation is plausible and that heavier COMs than GA and EG could exist in interstellar environments. We propose a general pathway involving radical-formaldehyde reactions as common initiation step for aldose and polyol formation. Future telescope observations may give additional clues on their presence in star-forming regions as observations are currently limited because of the detection thresholds.

Interaction of oxygen with polystyrene and polyethylene polymer films: A mechanistic study

In this work, first principles calculations combined with advanced surface diagnostics are used to unravel the mechanisms of plasma oxygen interaction with organic films of interest for advanced patterning in semiconductor device manufacturing. Results from a combination of x-ray photoelectron spectroscopy (XPS) diagnosed oxygen plasma exposed polystyrene films and first principles modeling of organic films (polystyrene, polyethylene, and derivatives) provide insights into how organic films are oxidized by oxygen atoms. XPS measurements show the rapid formation of C-O structures and their saturation after oxygen exposure on both pristine and argon bombarded polystyrene samples. Quantum mechanics calculations confirm that C-OH formation can be immediate without recourse to previously formed dangling bonds. Multiple oxygen impacts are required for scission of pristine ethylene carbon strands. Therefore, ethylene films can be converted to polyols that are stable, whereas more likely strands are broken before polyol formation through the formation of water and C=O. On the contrary, intermediate compounds with adjacent C=O bonds are not likely to form stable structures. The combination of XPS measurements and modeling implies that the oxidation of polystyrene and polyethylene is self-limiting on both hydrogen saturated and dehydrogenated (after argon ion plasma bombardment) surfaces.

Catalytic Hydrogenolysis of Biomass-derived Polyhydric Compounds to C2–C3 Small- Molecule Polyols: A Review

Biomass energy has attracted much attention because of its clean and renewable characteristics. At present, C2–C3 polyols such as glycerol, 1,2-propanediol, and ethylene glycol, widely used as platforms for downstream chemicals or directly used as chemicals in diversified industries, mainly depend on the petrochemical industry. In terms of the feedstock for C2–C3 polyol production, the C3-derived glycerol is a side product during biodiesel synthesis, whereas the C5-derived xylitol and C6-derived sorbitol can be mainly obtained by hydrolysis–hydrogenation of hemicellulose and cellulose from lignocellulosic biomass, respectively. In this review, we summarize the catalysts and catalysis for selective hydrogenolysis of these polyhydric compounds to C2–C3 polyols and introduce the reaction pathways for the target polyol formation based on the C3, C5, and C6 polyhydric alcohol hydrogenolysis. Finally, state-of-the-art technologies are described and the remaining challenges and further prospects are presented in view of the technical aspects.

Scratch Hardness Properties of Waste Palm Cooking Oil Based Polycaprolactone Urethane Coatings

Polyurethane has been widely used in various coating industries due to its good weathering resistance, promising appearance, excellent elasticity and good mechanical properties. The present work reports the development of polycaprolactone urethane coatings based on waste palm cooking oil (WPCO). WPCO was recycled to synthesis polycaprolactone (PCL) polyol using two-steps methods; transesterification and ring opening polymerization with various ratios of ε-CL to WPCO based polyesteramide. The WPCO based PCL polyols were reacted with isophorone diisocyanate (IPDI) to produce polycaprolactone urethane coatings. FTIR analyses were employed to confirm the formation of polyols and the scratch resistance properties of coatings were characterized by scratch hardness testing. The results revealed that the scratch resistance of polycaprolactone urethane coatings increased by increasing the ε-CL composition in the formulation.

Waterborne polyurethane-silica nanocomposite adhesives based on castor oil-recycled polyols: Effects of (3-aminopropyl)triethoxysilane (APTES) content on properties

Waterborne castor oil-recycled polyol based polyurethane-silica nanocomposite adhesives (WPU) with polymer matrix and silica nanoparticles chemically bonded have been successfully prepared through a sol-gel process. A series of waterborne polyurethane adhesives with hard segment contents from 71.3 to 74.5 wt%, were synthesized using an isophorone diisocyanate, 2-bis(hydroxymethyl) propionic acid, recycled castor oil-based as soft segments and (3-aminopropyl)triethoxysilane (APTES) as chain extender. The depolymerized oligoester obtained from glycolysis of poly(ethylene terephthalate) (PET) waste using triethylene glycol (TEG), was transesterified with castor oil (CO) which resulted in the formation of hydroxyl-functional polyester polyol, with hydroxyl value of 414 mgKOH g−1. The molecular structures and mass of glycolyzed PET oligoesters, castor oil-based polyol and castor oil-based polyurethane-silica nanocomposite adhesives were estimated by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The structure and properties of the resulting films were investigated by FTIR, wide angle X-ray diffraction measurement (XRD), thermogravimetry (TG) and differential scanning calorimetry (DSC). TG analysis indicated that APTES can improve the thermal stability of WPU. XRD showed that the crystallinity of WPU decreased with the increase alkoxysilane content. The extent of crosslinking was investigated to show a dependence on silica concentration, which increased the glass transition temperature and particle size of polyurethane nanocomposites with increasing alkoxysilane content due to the condensation of the alkoxysilane groups. The hardness, adhesion and gloss quality of the polyurethane films were also determined considering the effect of APTES content, so this paper confirmed the suitability of using these castor oil-based waterborne polyurethane-silica nanocomposites as new adhesive materials with high performance coatings materials. The experimental results reveal that the APTES and the hard segment content play a key role in controlling the structure and properties of the PU cast films based on castor oil-recycled polyols.

In vitro and in vivo evaluation of pterostilbene for the management of diabetic complications

BackgroundAldose reductase (AR) and Advanced glycation end product (AGE) are known to play important roles in the development of diabetic complications. The inhibitors of AR and AGE would be potential agents for the prevention of diabetic complications. ObjectiveThe present study was aimed to evaluate the aldose reductase (AR) and advanced glycation end product (AGE) inhibitory potential of pterostilbene for its possible role in the treatment of diabetic complications such as cataract. Materials and methodsThe compound was studied for its inhibitory activity against rat lens AR (RLAR) and rat kidney AR (RKAR) in vitro along with its ability to inhibit the formation of AGEs. Anticataract activity of pterostilbene was demonstrated using sugar induced lens opacity model in isolated cattle lens. Further, the involvement of pterostilbene in galactosemia in rats was investigated by assessing the key markers in the polyol pathway and the results were compared with that of a potent AR inhibitor, fidarestat. ResultsPterostilbene exhibited inhibitory activity against RLAR and RKAR with IC50 values of 5.49 mg/ml (21.4 mM) and 6.40 mg/ml (25.02 mM), respectively. In sugar-induced lens opacity model, pterostilbene displayed a significant protective effect by preventing opacification and formation of polyols in cattle lens. Besides, the compound exhibited in vivo inhibition of galactitol accumulation in lens and sciatic nerves of galactose fed rats. ConclusionThe results obtained in the study underline the potential of pterostilbene as possible therapeutic agent against long-term diabetic complications.

Preparation of Renewable Bio-Polyols from Two Species of Colliguaja for Rigid Polyurethane Foams.

In this study, we investigated the potential of two non-edible oil extracts from seeds of Colliguaja integerrima (CIO) and Colliguaja salicifolia (CSO) to use as a renewable source for polyols and, eventually, polyurethane foams or biodiesel. For this purpose, two novel polyols from the aforementioned oils were obtained in a one-single step reaction using a mixture of hydrogen peroxide and acetic acid. The polyol derivatives obtained from the two studied oils were characterized by spectral (FTIR, 1H NMR, and 13C NMR), physicochemical (e.g., chromatographic analysis, acid value, oxidizability values, iodine value, peroxide value, saponification number, kinematic viscosity, density, theorical molecular weight, hydroxyl number, and hydroxyl functionality) and thermal (TGA) analyses according to standard methods. Physicochemical results revealed that all parameters, with the exception of the iodine value, were higher for bio-polyols (CSP and CIP) compared to the starting oils. The NMR, TGA, and FTIR analyses demonstrated the formation of polyols. Finally, the OH functionality values for CIP and CSP were 4.50 and 5.00, respectively. This result indicated the possible used of CIP and CSP as a raw material for the preparation of polyurethane rigid foams.

Effect of the silica nanofiller on the properties of castor oil-based waterborne polyurethane hybrid dispersions based on recycled PET waste

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.

Synthesis of polyurethane dispersion from polyesteramide polyol

Purpose The study aims to synthesise polyurethane dispersion from polyesteramide polyol. The polyesteramide polyol is a novel polyol for the synthesis of polyurethane dispersion. Design/methodology/approach Polyesteramide polyol has been synthesised from phthalic anhydride and fatty amide of mustard oil. Aminolysis of mustard oil had been carried out with diethanolamine. The novel polyurethane dispersion had been synthesised using a polyesteramide polyol as a precursor. Isophorone diisocyanate was used as an isocyanate component and polyurethane dispersion (PUDs) had been synthesised by an anionic method where DMPA was introduced to introduce –COOH groups as via grafting to the resin backbone. Triethylamine was used for neutralisation and, hence, for further dispersion in water. Hydroxyl ethyl methacrylate was used for the synthesis to introduce unsaturation in the backbone of PUDs. The coating was made by an UV curing process. The coating was characterised for mechanical properties, chemical properties, thermal properties as well as stain resistance. Findings The polyurethane dispersion formed through it has ester and amide linkage present in it. The acetone process is used for its synthesis. The nuclear magnetic resonance spectroscopy confirms the successful formation of polyesteramide polyol and PUDs. Even though long aliphatic chains present in polyol which may impart hydrophobicity the synthesis PUDs well dispersed in water. It is observed as the coating made from it have hardness and scratch resistance properties. The coating also exhibits good stain resistance properties. Practical implications The method is an easy one to synthesise polyurethane dispersion from polyesteramide polyol, which is based on ester and amide linkage. Originality/value To the best of the authors’ knowledge, this is the first report on synthesised polyurethane dispersion from polyesteramide polyol. The polyesteramide resin already proves its excellence and upcoming technology in the coating industry. Here, they are incorporated into the synthesis of polyurethane dispersion.