Neopentyl Glycol Research Articles

Optimization and lubrication properties of Malaysian crude palm oil fatty acids based neopentyl glycol diester green biolubricant

Green biolubricant base stock based on crude palm oil fatty acids (CPOFAs) was produced through acid catalyst esterification of palm oil fatty acids with neopentyl glycol (NPG). The response surface methodology (RSM) of D-optimal design was employed to optimize the esterification process. The resultant polyol ester, crude palm oil fatty acids-NPG diester (CPOFAs-NPGDE) was evaluated its lubrication properties. The optimal condition for the esterification process was obtained at CPOFAs:NPG molar ratio of 2.26:1, 1.12% H2SO4 catalyst, reaction temperature of 138 °C for 4.79 h reaction time, respectively. The optimal CPOFAs-NPGDE produced was 87.6% yield with 100% diester selectivity. The resultant ester showed good lubrication properties with oxidative stability temperature at 184 °C, pour point at 10 °C, flash point at 235 °C and viscosity index of 190. Tribological tests showed that COFAs-NPGDE has shown low coefficient friction of hydrodynamic regime of 0.20 at 40 °C and 0.19 at 100 °C and comparable with some commercial lubricants. Rheological tests show that CPOFAs-NPGDE can be classified as a Newtonian fluid with good lubrication properties within ISO VG 46 lubricant grade. This make it plausible to be used for green industrial lubrication applications such as hydraulic oil, compressor and turbine fluids.

Design of Deep Eutectic Systems: Plastic Crystalline Materials as Constituents.

Deep eutectic solvents (DESs) are a class of green and tunable solvents that can be formed by mixing constituents having very low melting entropies and enthalpies. As types of materials that meet these requirements, plastic crystalline materials (PCs) with highly symmetrical and disordered crystal structures can be envisaged as promising DES constituents. In this work, three PCs, namely, neopentyl alcohol, pivalic acid, and neopentyl glycol, were studied as DES constituents. The solid–plastic transitions and melting properties of the pure PCs were studied using differential scanning calorimetry. The solid–liquid equilibrium phase diagrams of four eutectic systems containing the three PCs, i.e., L-menthol/neopentyl alcohol, L-menthol/pivalic acid, L-menthol/neopentyl glycol, and choline chloride/neopentyl glycol, were measured. Despite showing near-ideal behavior, the four studied eutectic systems exhibited depressions at the eutectic points, relative to the melting temperatures of the pure constituents, that were similar to or even larger than those of strongly nonideal eutectic systems. These findings highlight that a DES can be formed when PCs are used as constituents, even if the eutectic system is ideal.

A Convenient U-Shape Microreactor for Continuous Flow Biocatalysis with Enzyme-Coated Magnetic Nanoparticles-Lipase-Catalyzed Enantiomer Selective Acylation of 4-(Morpholin-4-yl)butan-2-ol

This study implements a convenient microreactor for biocatalysis with enzymes immobilized on magnetic nanoparticles (MNPs). The enzyme immobilized onto MNPs by adsorption or by covalent bonds was lipase B from Candida antarctica (CaLB). The MNPs for adsorption were obtained by covering the magnetite core with a silica shell and later with hexadecyltrimethoxysilane, while for covalent immobilization, the silica-covered MNPs were functionalized by a layer forming from mixtures of hexadecyl- and 3-(2-aminoethylamino)propyldimethoxymethylsilanes in 16:1 molar ratio, which was further activated with neopentyl glycol diglycidyl ether (NGDE). The resulting CaLB-MNPs were tested in a convenient continuous flow system, created by 3D printing to hold six adjustable permanent magnets beneath a polytetrafluoroethylene tube (PTFE) to anchor the MNP biocatalyst inside the tube reactor. The anchored CaLB-MNPs formed reaction chambers in the tube for passing the fluid through and above the MNP biocatalysts, thus increasing the mixing during the fluid flow and resulting in enhanced activity of CaLB on MNPs. The enantiomer selective acylation of 4-(morpholin-4-yl)butan-2-ol (±)-1, being the chiral alcohol constituent of the mucolytic drug Fedrilate, was carried out by CaLB-MNPs in the U-shape reactor. The CaLB-MNPs in the U-shape reactor were compared in batch reactions to the lyophilized CaLB and to the CaLB-MNPs using the same reaction composition, and the same amounts of CaLB showed similar or higher activity in flow mode and superior activity as compared to the lyophilized powder form. The U-shape permanent magnet design represents a general and easy-to-access implementation of MNP-based flow microreactors, being useful for many biotransformations and reducing costly and time-consuming downstream processes.

Synthesis of Unsaturated Polyester Resin Based on Pet Waste

Abstract: Polyethylene terephthalate (PET) flakes are widely used as raw material for manufacturing of packaging materials. The worldwide production of PET is 30.5 million metric tons/year. With such a large consumption, the effective application of PET waste is of considerable commercial and technological significance. In this paper we used PET flakes for the synthesis of unsaturated polyester resin to go green. PET flakes were depolymerized by using Neopentyl glycol (NPG) and propylene glycol (PG). Glycolyzed product was reacted with maleic anhydride and phthalic anhydride. Then it was mixed with styrene monomer to get unsaturated polyester (UP) resins. Molecular weight, Hydroxyl value and Acid value of all synthesized UP resins were studied.

Liquid-liquid phase equilibria for the ternary (neopentyl glycol + sodium formate + water) system

ABSTRACT. Liquid–liquid equilibrium data and the phase diagrams were measured for the ternary (neopentyl glycol + sodium formate + water) system at various temperatures of 303.15, 313.15 and 323.15 K. The effect of temperature on the conjugate phase and the tie-line length of the investigated system have been studied. The results showed that the length of the tie-line increases and the two-phase area was slightly increased by decreasing temperature. The fitting parameters of the Pirdashti and Merchuk equations were obtained with the temperature dependence expressed in the linear form, respectively. Compared with the Pirdashti equation, the binodal curves were satisfactorily described using the Merchuk equation at T = (303.15, 313.15 and 323.15) K, and the critical points at different temperatures were estimated by extrapolation. Furthermore, the Hand, Othmer-Tobias and Bachman models were used for the correlation of the phase behavior of the studied system. According to the reported correlation coefficients values, it was found that the measured tie-line data have acceptable consistency and the better fitness was with Othmer-Tobias equation. 
 
 KEY WORDS: Liquid–liquid equilibrium, Neopentyl glycol, Phase diagram, Merchuk
 Bull. Chem. Soc. Ethiop. 2022, 36(4), 915-922. 
 DOI: https://dx.doi.org/10.4314/bcse.v36i4.16

A Liquid Chromatography-Mass Spectrometry Method to Study the Interaction between Membrane Proteins and Low-Molecular-Weight Compound Mixtures.

Molecular interaction analysis is an essential technique for the study of biomolecular functions and the development of new drugs. Most current methods generally require manipulation to immobilize or label molecules, and require advance identification of at least one of the two molecules in the reaction. In this study, we succeeded in detecting the interaction of low-molecular-weight (LMW) compounds with a membrane protein mixture derived from cultured cells expressing target membrane proteins by using the size exclusion chromatography-mass spectrometry (SEC-MS) method under the condition of 0.001% lauryl maltose neopentyl glycol as detergent and atmospheric pressure chemical ionization. This method allowed us to analyze the interaction of a mixture of medicinal herbal ingredients with a mixture of membrane proteins to identify the two interacting ingredients. As it does not require specialized equipment (e.g., a two-dimensional liquid chromatography system), this SEC-MS method enables the analysis of interactions between LMW compounds and relatively high-expressed membrane proteins without immobilization or derivatization of the molecules.

Probing hydrogen-bond networks in plastic crystals with terahertz and infrared spectroscopy

A molecular-level understanding of phase changes in hydrogen-bonded solid-state systems is of great importance in fields spanning thermal science to medical therapeutics. Polyols have recently emerged as prime targets for deployment, given their versatility in phase-induced changes, and occupy a deep space in eutectic solvents. Here, we explore the hydrogen-bond network of neopentyl glycol (NPG) with terahertz time-domain spectroscopy, attenuated total reflection spectroscopy in the far- and mid-infrared regions augmented by electronic structure calculations. A picture emerges where vibrational spectroscopy can exquisitely probe a crystalline to amorphous solid-solid phase transition while spectroscopy in the mid-infrared region provides a molecular picture of the phase transition. These methods are then applied to understand the thermal properties and phase changes in NPG upon incorporation of bis(trifluoromethane)-sulfonimide lithium salt, to demonstrate that vibrational spectroscopy can directly probe the disruption of hydrogen-bond networks in plastic crystals.

The Effect of Glycol Derivatives on the Properties of Bio-Based Unsaturated Polyesters.

The scope of the present study was to prepare fully bio-based unsaturated polyester resins (UPRs) with comparable properties to the commercial formulations. The focus was set on the determination of the optimal prepolymer formulation using the same set of diacids (itaconic and succinic acid) and different diols (propylene glycol, isosorbide and neopentyl glycol) or its equimolar mixtures, keeping the fixed molar ratio of 1:1:2.1 in all feed compositions. Instead of commonly used styrene, bio-based dimethyl itaconate was used as a reactive diluent (RD). The rheology of the obtained resins was studied in detail. The effect of the used diol on structural (FTIR), thermal (DSC), thermomechanical (DMA), and mechanical (tensile) properties was explained. The properties of UPRs were found to be highly dependent on the diol used in the prepolymer formulation. The UPR with an equimolar ratio of propylene glycol and neopentyl glycol was shown to be the most promising candidate to compete with the commercial petroleum-based resins.

A novel class of bio-lubricants are synthesized by epoxidation of 10-undecylenic acid-based esters

Mineral-based lubricants are being supplanted by bio-based lubricants because of environmental concerns and the depletion of fossil resources. The derivatives of edible and non-edible oils are considered potential alternatives to existing natural mineral oil base stocks in certain lubricant applications, where immediate intraction with the environment is predicted. A new class of epoxides were synthesized from the undecylenic esters of 2-ethyl hexanol, neopentyl glycol (NPG), and trimethylolpropane (TMP). These unsaturated esters were epoxidized by using meta chloro perbenzoic acid. The synthesized epoxides were characterized by spectral studies (1HNMR, 13CNMR, IR) physio-chemical (density, specific gravity) and lubricant properties (kinematic viscosity, viscosity index, flash point, fire point, cloud point, pour point, copper strip corrosion). TMP epoxide has a high viscosity index, high flash point, and low pour point compared to 2-ethyl hexyl epoxide and NPG epoxide.

Improvement of CO2 absorption and inhibition of NH3 escape during CaCO3 precipitation in the presence of selected alcohols and polyols

This research aims to investigate the effect of selected organic substances containing hydroxyl groups on the reduction of NH3 escape and the improvement of CO2 capture during the precipitation of calcium carbonate by carbonation method using post-distillation liquid from the Solvay process and gas stream containing CO2 in the amount corresponding to the exhausted gases produced by the combustion of fossil fuels. Glycerol, ethylene glycol (EG), methanol, isopropanol, pentaerythritol, and neopentyl glycol (NPG) were used as ammonia escape inhibitors. The addition of NPG has been shown to result in the highest reduction of NH3 escape (83.1%) and the highest CO2 capture efficiency (86.1%). During the proposed CaCO3 precipitation with NPG, 98.7% of the NH3 initially introduced into the reaction mixture remains in the solution. Furthermore, the features that should be taken into account when introducing various alcohols and polyols for capturing NH3 and CO2 in the calcium carbonate precipitation via the carbonation method have been discussed.

BASF says 5 of its chemical building blocks are low-CO2

BASF is in the process of calculating the carbon footprints of each product in its portfolio and making the reports available to its customers, according to executives. The firm says it has found that its system for making five chemical intermediates is significantly lower in carbon emissions than the industry averages for those chemicals: tert -butylamine, formic acid, propionic acid, 1,6-hexanediol, and neopentyl glycol. The carbon scores include raw materials, transportation, energy inputs, and process emissions.

Thorough investigation of non-volatile substances extractible from inner coatings of metallic cans and their occurrence in the canned vegetables

Since the decline of the use of bisphenol A, the chemistry of the varnishes and coatings which are applied to the inner surfaces of metallic food contact materials is poorly documented. We hypothesised that can coatings are now diverse and bring forth various non-intentionally added substances (NIAS) to be described. Investigating complex components such as NIAS requires demanding non-targeted approaches. We investigated the coatings of 12 vegetable cans from the French market. More than 125 substances were pinpointed, among them 84 oligoester combinations from 8 diols and 4 diacids. Thus, oligoesters were the dominant family. Additives such as epoxidised soybean oil, bisphenol A diglycidyl ether and benzoguanamine derivatives and phenol-formaldehyde oligomers were also identified. A software for exploring databases of theoretical combinations of polyester and phenol-formaldehyde resin components (NIAS-db 1.0) was made available. The stepwise organic synthesis of native and deuterated combinations of neopentyl glycol and isophthalic acid (4 and 8 units, linear and cyclic) enabled a higher confidence level and monitoring in vegetable extracts. Migration of oligoesters averaged 330 µg/kg in the drained vegetables (43–1600 µg/kg). This study sheds light on the need to fulfil a proper risk assessment on this NIAS family (exposure and hazard characterisation).

Preparation and UV‐curing properties of oxazolidine‐2‐one based acrylates

AbstractThree oxazolidine‐2‐one based acrylates monomers were synthesized by the reaction of oxazolidine‐2‐one with 1,6‐hexanediol diacrylate (HDDA), neopentyl glycol diacrylate (NPGDA) and trimethylolpropane triacrylate (TMPTA). The molecular structures of the products were characterized by FT‐IR, 1H NMR and electrospray ionization high resolution mass spectrometry (ESI‐HRMS). The photo‐polymerization kinetics of the synthesized oxazolidine‐2‐one based acrylates were investigated by real‐time infrared spectroscopy. The results showed that the oxazolidine‐2‐one based acrylates with 1 wt% 2‐isopropylthioxanthone (ITX) could be cured to form a transparent film under UV irradiation. The UV curing speed of oxazolidine‐2‐one based acrylates with 1 wt% ITX was better than that of TMPTA with 1 wt% ITX and 3 wt% ethyl 4‐(dimethylamino) benzoate (EDB) as co‐initiator. Based on the HRMS analysis of oligomers extracted from the UV‐cured film, the plausible photopolymerization mechanism was proposed. The synthesized monomer formula with CN996 resin can be 3D printed forming various models with smooth surface, good accuracy, excellent thermal stability and 99.4% gel content.

Preparation and UV curing properties of oxazolidinone-based acrylate derivatives

The oxazolidinone-based acrylate derivatives were prepared by the oxa-Michael addition reaction of neopentyl glycol diacrylate (NPGDA), trimethylolpropane triacrylate (TMPTA) and ethylene glycol dimethacrylate (EGDMA) with 3-(2-hydroxyethyl)-2-oxazolidinone (Z1), which was prepared by the reaction of dimethyl carbonate (DMC) with diethanolamine (DEA). The molecular structures of the products were characterized by FT-IR, 1H NMR and electrospray ionization high resolution mass spectrometry (ESI-HRMS). Under initiated by 1 wt% 2-isopropyl-9H-thioxanthen-9-one (ITX) and 1 wt% 2-hydroxy-2-methyl-1-phenylpropan-1-one (Da-1173), the oxazolidinone- based acrylates were cured in 30 s with double bond conversion of 92% and 98%, respectively. The photopolymerization activity is in the order of oxazolidinone-based acrylate > conventional acrylate with 3 wt% EDB > conventional acrylate. The first-order kinetics for oxazolidinone part indicates that the oxazolidinone group is a hydrogen donor, which can terminate the polymeric radicals, forming an active radical to re-initiate the polymerization. HRMS analysis of oligomers extracted from the UV-cured film of butyl acrylate confirms further the role of oxazolidinone part, and the plausible UV polymerization mechanism was proposed. The composition of addition product of TMPTA with Z1 (named as TMPTA-Z1) with epoxy acrylate can be 3D printed forming various models with the hardness of 5H.

Nano-enhanced phase change material for thermal comfort at skull and environment interface in riding helmets: An experimental investigation

In arid climes, the thermal discomfort experienced by motorcycle riders affects their physical and mental wellbeing. This paper proposes a novel approach to cool the interior region of helmets using nano-enhanced organic Phase Change Material (PCM). The solid-solid phase change of organic Neopentylglycol (NPG) PCM, having a solid–solid latent heat of 98 kJ/kg is used in this work. Its phase transition temperature and thermal conductivity are respectively between 39 °C - 47 °C and 0.1–0.15 W/m-K. To enhance the thermal conductivity of organic NPG, it is added with CuO, Al2O3, and TiO2 nanoparticles in 0.1% by mass. The Pure and nano-enhanced samples are initially heated up to 100 cycles. The characterization processes namely the Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), and Fourier Transform Infrared Spectroscopy (FTIR) are used to analyse its thermal characteristics, thermal and chemical stoutness respectively. The DSC test result shows that for NPG + 0.1% CuO, NPG + 0.1% Al2O3, NPG + 0.1% TiO2, and pure NPG samples, the respective solid-solid transition latent heats are 92.22 kJ/kg, 91.25 kJ/kg, 90.05 kJ/kg, and 94 kJ/kg. The transition peaks for the aforesaid samples are 43.4 °C, 43.8 °C, 42.9 °C, and 43.7 °C. After 100 thermal cycles, the decrease in the solid-solid transition latent heat is 3.06%, 3.23%, 3.27%, and 2.78% respectively. The TGA and FTIR results show that the thermal and chemical stability of NPG are not significantly affected, either by nanoparticle addition or thermal cycling. At the later stage, the variation in heat conductivity and specific heat capacity are evaluated by the Temperature – history (T-history) method. The result reveals that the thermal conductivities of nano-enhanced test samples (0.1% CuO, 0.1% Al2O3, and 0.1% TiO2) have increased by 14.67%, 11.92%, and 8.26% respectively. Among all the samples, NPG + 0.1% CuO has exhibited more promising results than pure and other nano-enhanced NPG samples. The interior temperature of two identical helmets, one made with 0.1% CuO blended NPG and the other without PCM, have been experimentally analyzed. The initiation of solid-solid transition of NPG has reduced the interior surface temperature by approximately 20% than the latter and thus, the nano-enhanced PCM incorporated helmet can maintain the comfort level for a sufficiently long period.

Glycidate as a High-Strength Epoxy Adhesive Curable with Amine under Ambient Conditions.

This paper reports that glycidates bearing epoxy moieties with adjacent ester can be cured with diethylenetriamine (DETA) under mild conditions and exhibit high adhesiveness. Curing of bifunctional glycidates with DETA gave cross-linked products. The curing started at a lower temperature (7 °C) than the analogous glycidyl ether (27 °C), while the rate of the curing was slower due to the lower activation energy (Ea = 57 kJ/g) and exothermicity (ΔH = 58 J/g) as confirmed by DSC analysis. The curing system of neopentyl glycol diglycidate and DETA effectively adhered aluminum plates by curing at 25 °C, and the strength was more than five times higher than the curing with analogous glycidyl ether. The higher adhesive strength under curing of ambient conditions and facile preparation of monomers are the significant advantages of this curing.

Atomic-scale insights into the colossal barocaloric effects of neopentyl glycol plastic crystals

Neopentyl glycol has become an important candidate material for solid-state refrigeration in the future because of its environmental protection, high energy efficiency, high stability, and economy. However, the complete micro-dynamic mechanism remains to be established, which restricts its further applications. In this work, we investigate one representative material-plastic crystal neopentyl glycol (NPG) by means of large-scale molecular dynamics simulation. It is found that NPG exhibits colossal barocaloric effects (CBCEs) with high isothermal entropy changes and potentially large adiabatic temperature changes, which closely relates to the reversible order disorder change in NPG's molecular orientation, in which the non-bond interaction between molecules plays a key role. Further analysis of orientational dynamics and hydrogen bond energy during phase transition along with pressure dependent thermal conductivity sheds light on the underlying microscopic mechanism. Our work reveals the molecular mechanism of CBCEs in NPG as a prototypical plastic crystal, providing valuable insight into achieving practical caloric materials in future cooling technology.

Synergistic flame retardancy of linear low-density polyethylene with surface modified intumescent flame retardant and zinc borate

Aluminum diethylphosphinate (ADP) was surface modified with the silane coupling agent KH-560, and mixed intumescent flame retardants (IFRs) were prepared with neopentyl glycol (NPG) and melamine (MEL). Then mixed IFRs and zinc borate (ZB) were compounded and added into linear low-density polyethylene (LLDPE) material. The morphology, composition, and structure of LLDPE/IFRs/ZB composites were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The maximum limiting oxygen index of LLDPE/IFRs/ZB composites is 28.7%, and the combustion grade is V0. The thermogravimetric analysis results showed that the thermal degradation rate of LLDPE/IFRs/ZB composites decreased, and the carbon residue reached 15.3 wt% at 700 ℃. The cone calorimeter test showed that peak heat release rate (PHRR), total heat release rate (THR), peak smoke release rate (PSPR), and total flue gas output (TSP) of LLDPE/IFRs/ZB composites decreased by 52.5%, 24.7%, 30%, and 15.5%, respectively, compared with pure LLDPE, significantly improving the flame retardant and smoke suppression performances of LLDPE. The residual carbon analysis shows that the CC and POC bonds in the modified mixed IFR strengthen the carbon layer structure and form a denser intumescent carbon layer, effectively hindering flame propagation. The experimental results show that the new intumescent flame retardant is a remarkable breakthrough in both flame retardancy and smoke suppression compared with ordinary intumescent flame retardants, and is more suitable for flame retardant polymer materials than traditional intumescent flame retardants.

Influence of intraparticle cross-linking on polymer diffusion in latex films prepared from secondary dispersions

In this work, we synthesized surfactant-free latex dispersions of nanoparticles (NPs) based upon emulsification of a preformed proprietary BASF polymer (MnGPC = 5000 g/mol, Ð = 3, denoted as Pol), in which the —COOH groups were partially neutralized by ammonia. To obtain useful coatings with polymers of such low molecular weight (MW), we approached this problem through the reaction of carboxylated polymer dispersions with neopentyl glycol diglycidyl ether (NGDE, 20 to 60 mol% based on carboxyl groups) to increase the MW and to introduce gel content. We employed AFM to monitor the influence of cross-link density on the surface roughness and found the presence of cross-links increases the resistance of particles to deformation. Fluorescence resonance energy transfer (FRET) measurements were carried out to determine the extent of polymer mixing upon film formation. Our most important finding is that the gel content substantially limited the extent of molecular mixing at long annealing times or in corresponding solvent-cast films. In parallel, we carried out a series of similar reactions on the secondary dispersion particles with a monoepoxide, consisting of a mixture of dodecyl and tetradecyl glycidyl ether. This reaction maintained the size and size distribution of the latex particles. These polymers had no gel content, but the reaction with the epoxide lowered the Tg of the polymer. FRET studies showed a pronounced influence of Tg on the rates of polymer diffusion in these films.

Partially Dehydrated Castor Oil-Based Isoalkyl and Polyol Esters as Potential Base Stocks for Industrial Applications

Partially dehydrated castor oil (PDCO) which is of less use in the paint and furniture coating formulations has been modified to develop biolubricant base stocks. PDCO (44.1%, non-conjugated linoleic acid; 32%, conjugated linoleic acid (18:2) isomers and 15.3% ricinoleic acid) obtained from a local industry was hydrolyzed under alkaline conditions. The fatty acids obtained (PDCFAs) in 98% yields were reacted with polyols namely 2-ethyl hexanol, neopentyl glycol, trimethylol propyl, pentaerythritol to obtain respective isoalkyl erters and esters of polyol with >95% yield. The base stocks exhibited very high viscosity indices (187.288 to 187.687), excellent pour point (-25 to -40 ºC) and high flash points (212 to 317 ºC) required for a variety of industrial applications namely metal working, hydraulic, forging, cutting fluid, gear oil applications. The tribological properties of PDCO, exhibited very low WSD (0.72-0.79 mm) and WSVs (0.82-0.83 mm3) with high load carrying capacities (180-220 kg) indicating low friction and less energy losses between the sliding surfaces. This was also accompanied by very high thermo-oxidation stabilities [Oxidation stability (230-242 ºC); Onset temperature (300-381 ºC)] of the base stacks due to branching. Overall all the PDCO isoalkyl and polyol esters exhibited excellent properties suitable for a wide range of industrial applications on par with mineral oil based lubricants.