Polyol Reaction Research Articles

Development of a Novel Support Modification for Efficient Lipase Immobilization: Preparation, Characterization, and Application for Bio-flavor Production

The low cost and excellent catalytic properties of lipase for industrial processes are highly desirable. A promising new approach involves the support modification of lipase and spacer arm, which enables the enhancement of lipase properties. This study investigates the immobilization of crude lipase from Mucor miehei onto a Polyurethane Foam (PUF) surface using various coating techniques. The PUF matrix was obtained through isocyanate and polyol reactions. Subsequently, the PUF was coated by adsorbing lipase and adding edible support material. The immobilized lipase was then utilized in the hydrolysis of coconut oil to produce fatty acids. Furthermore, the immobilized enzyme was employed in the esterification of fatty acids to produce bio-flavors. The results demonstrate that the attachment reaction using support material, namely lecithin, gelatin, MgCl2, and Polyethylene glycol 6000 (PEG), all of which are simple and edible, was able to enhance the stability and reusability of lipase. This immobilization technique increased triglyceride hydrolysis into FFA by 422%. The successful edible support modification of immobilized lipase from M. miehei on PUF, coupled with significantly enhanced enzyme stability and catalytic activity, offers a promising, environmentally friendly solution for diverse applications in the food industry. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Morphology Controled LiFePO4 Electrodes Via Polyol Refluxing for Enhanced Lithium-Ion Battery Performance

In the synthesis of LiFePO4 cathodes with secondary nanorod structures and nano-plate morphologies, researchers utilized a polyol refluxing process. Notably, we achieved this without the use of characteristic structure directing agents. Through varying the reaction time, they were able to modulate the morphological characteristics of the synthesized samples.X-ray diffraction studies conducted on the prepared samples indicated a highly crystalline nature. This suggests that the synthesized cathodes possessed a robust and ordered atomic structure, which is crucial for their electrochemical performance.Electron microscopy investigations provided insights into the morphology of the samples obtained at different reaction times. Samples produced after 1 to 16 hours of polyol reaction exhibited secondary nanorod bundles. However, the sample recovered after 32 hours of polyol reaction displayed a distinct nano-plate morphology. These observations highlight the influence of reaction time on the final morphology of the synthesized cathodes.The dimensions of the obtained samples ranged from a few tens to a few hundred nanometers. This nano-scale size is advantageous for enhancing the electrode's surface area, which can facilitate rapid ion diffusion and electron transport during battery cycling.When employed in lithium test cells, the LiFePO4 cathodes synthesized for different durations delivered varying discharge capacities. Specifically, cathodes prepared under 1, 4, 8, 16, and 32 hours of reaction time exhibited discharge capacities of 161, 162, 171, 143, and 155 mAhg−1, respectively. Notably, all samples displayed a well-defined discharge plateau at 3.4 V, indicating stable electrochemical behavior during cycling.Remarkably, among the prepared electrodes, the LiFePO4 nanorod bundle cathode synthesized under 1 hour reaction time demonstrated the highest average reversible capacities. It maintained capacities of 123 and 103 mAhg−1 at C-rates as high as 3.2 and 6.4 C, respectively. This highlights the importance of reaction time in controlling the electrochemical performance of the synthesized cathodes.The crystal growth mechanism during the polyol refluxing method can be elucidated through several stages. These include precursor dissolution and nucleation, oriented crystal growth and alignment through self-assembly, aggregation, partial dissolution, and finally, complete re-crystallization. Understanding these mechanisms is essential for optimizing the synthesis process and tailoring the properties of LiFePO4 cathodes for various applications. Tarascon JM, Armand M. Issues and challenges facing rechargeable lithium batteries. Nature 2001;414:359–67Amatucci GG, Tarascon JM, Klein LC. CoO2, the end member of the LixCoO2 solid solution. J Electrochem Soc 1996;143:1114–23Ravet N, Chouinard Y, Magnan JF, Besner S, Gauthier M, Armand M. Electroactivity of natural and synthetic triphylite. J Power Sources 2001;97–98:503–7 Figure 1

The Investigation of Macro Structure of Composite Material Mixed Rice Husk with Polyurethane as Insulation Material in Fish Cold Storage Boxes


 
 
 
 This research aims to investigate the macro structure of a composite material mixed with rice husk and polyurethane. Determine the material with the best composition to apply to the cooler or fish storage area. The urgency of this research is the application of appropriate technological concepts to support the cold chain system so that the quality of fishermen's catches can be maintained. One of the efforts made is to make composite materials for insulation from a mixture of rice husks and polyurethane with various composition ratios ranging from 1:0.5 to 1:2 polyurethane-rice husks. The results of the research show that each composition obtains different results. From the macro photo test resultsed it shows that the lowest maximum area is in the 1:2 composition, namely 1:2A 14393, 1:2B 5232, 1:2C 4013. From all the test results, the composition is 1:2 is the most feasible material for making fish cooler box insulation because, this composition does not affect the expansion of the polyol and issocianate reaction
 
 
 

Preparation and characterization of potato crust-based polyurethane foam-I

Polyurethanes (PUs) are polymers obtained by reacting diisocyanates with a group of polyols. The first synthesized PU compounds were prepared using petroleum subproduct compounds. In this research study, biomass-containing polyols, which have been studied by other scientists, were prepared using potato crust and polymerized with diisocyanates to produce PU foam. Polyol reactions were carried out using the microwave heating method. Synthesis reactions and structural properties of polyols have been studied in many aspects. The most available polyol was used for PU synthesis. Different formulations were tried for PU synthesis and as a result, PU foam containing nearly 25% starch-polyol was synthesized. The chemical structure of PU polymer was identified by ATR-FTIR spectroscopy and crystallographic properties by WA-XRD analysis. The physical and mechanical properties of PU foam, which is used as a large number of building and construction materials, including thermal insulation materials, were evaluated by comparing them with a commercial PU foam. According to the results of our research, it was detected that the incorporation of biomass into the structure of PU polymer improved its density, heat conduction coefficient, pressure based mechanical properties. PU foam derived from potato waste has a WA XRD-ray diffraction peak between 13.1-28.5o. This data is between 12.5-23o in synthetic commercial foam and has been positively improved in the product we synthesized as a result of combining biomass into the structure. The synthesized biomass-based PU foam can be used as thermal insulation material. Biomass-based PU foam has been synthesized with features that can be used as a thermal insulation material.

Formation of LiNbO3 Nanocrystals Using the Solvothermal Method

The optimization of the parameters of the solvothermal synthesis of lithium niobate (LiNbO3, LN) nanocrystals from Nb2O5 and LiOH was performed. The effects of polyol media, reaction time and Li excess of the starting reagents were investigated. According to the X-ray diffraction phase analysis, Li3NbO4 and Nb2O5 were also detected besides the LN phase in many samples depending on the ratio of the starting components and the reaction time. The best yield and the most homogeneous LN phase was prepared by using diethylene glycol medium with a Li/Nb ratio of 1.5 and a 72 h reaction time. The size and the shape of the LN particles were characterized by scanning electron microscopy. The particle size distribution was narrow and under 100 nm for all cases.

The dynamic response and damage models of rebar reinforced polymer slabs subjected to contact and near-field explosions

Non aqueous reactive polymer materials produced by the reaction of isocyanate and polyol have been widely used in infrastructure construction, which may be subjected to explosion loads during complex service conditions. The blast response of composite materials is a crucial aspect for applications in engineering structures potentially subjected to extreme loadings. In this work, damage caused to rebar reinforced polymer slabs by surface explosive charges was studied experimentally and numerically. A total of 6 field tests were carried out to investigate the performances of the failure modes of rebar reinforced polymer slabs under contact and near-field explosions. The influence of explosive quantity (10–40 g) and stand-off distances (0–20 cm) at the damage modes were studied. The results show that the failure modes of rebar reinforced polymer slabs under near-field explosion mainly were bending and surface spalling, while under the impact of contact explosion, the failure modes were craters of the top surface, spalling of the bottom surface, and middle perforation. Furthermore, a detailed fully coupled model was developed and validated with the test data. The influences of explosive quantity and slab thickness on rebar reinforced polymer slabs under contact explosion were studied. Based on this, the calculation formula between breach diameter, explosive quantity, and slab thickness is fitted.

Utilization of carbon dioxide for preparation of polyurethane coatings without using the toxic isocyanates

Carbon dioxide (CO2) which is an infinite carbon resource in gaseous form is utilized for many industrial purposes and for the synthesis of materials. In this work, it is being used for the preparation of polyurethanes (PU) using 2-dioxolone (cyclic carbonate) and amine chemistry. Since the conventional polyurethanes are synthesized by the reaction of polyols and the toxic diisocyanates, there is need of adopting an environment-friendly route. Glycidyl methacrylate (GMA) was copolymerized with methyl methacrylate and butyl acrylate in presence of azobisisobutyronitrile as initiator and dimethyl sulfoxide (DMSO) as solvent. In parallel, by reacting with CO2 the epoxide groups of glycidyl methacrylate were converted into 2-dioxolone groups, using tetrabutylammonium bromide (TBAB) as a catalyst. When these 2-dioxolone groups present in the polymer structure were reacted with the primary diamine group of a curing agent, urethane linkage was created without using the toxic isocyanates. The Fourier Transform Infra-Red (FTIR) Spectroscopy reports confirmed the respective conversions. The polyurethane films thus formed after baking, were evaluated for mechanical properties, gloss, and water resistance, and found to be suitable for the topcoat application. This method thus utilizes CO2 for the transformation of epoxide groups to urethane linkages.

Synthesis and characterization of interpenetrating polymer networks (IPNs) based on UV curable resin and blocked isocyanate/polyols

Interpenetrating polymer networks (IPNs) are a non-bonded combination of two or more cross-linked polymers and have superior mechanical properties. Herein we synthesized a series of IPNs by a sequential UV-thermal dual-curing method, which is consisted of UV curable resin network and polyurethanes (PU) network. Blocked isocyanate (BI), polyols, and UV curable resin solutions were mixing completely, the resulting mixture was exposed to UV light to obtain a single network. Then the double network was formed via thermally triggered reaction of deblocking-isocyanate and polyols. The effect of polyol hydroxyl number (from two to six) on properties of IPNs was systematically studied. The results exhibit that pentaerythritol as polyol can be dual-cured by UV and heating to give the highest tensile strength (17.5 MPa), of a 21% increase compared to unheated sample. Furthermore, a series of semi-interpenetrating networks (semi-IPNs) were obtained by using polytetramethylene ether glycol (PTMEG) instead of the polyols. The results showed that introducing interpenetrating or semi-interpenetrating networks exhibit improved mechanical properties of the UV curable resin. Besides, the deblocking temperature of BI is just appropriate for the 3D-printing temperature.

Competition between CO2-philicity and Mixing Entropy Leads to CO2 Solubility Maximum in Polyether Polyols.

In carbon dioxide-blown polymer foams, the solubility of carbon dioxide (CO2) in the polymer profoundly shapes the structure and, consequently, the physical properties of the foam. One such foam is polyurethane—commonly used for thermal insulation, acoustic insulation, and cushioning—which increasingly relies on CO2 to replace environmentally harmful blowing agents. Polyurethane is produced through the reaction of isocyanate and polyol, of which the polyol has the higher capacity for dissolving CO2. While previous studies have suggested the importance of the effect of hydroxyl end groups on CO2 solubility in short polyols (<1000 g/mol), their effect in polyols with higher molecular weight (≥1000 g/mol) and higher functionality (>2 hydroxyls per chain)—as are commonly used in polyurethane foams—has not been reported. Here, we show that the solubility of CO2 in polyether polyols decreases with molecular weight above 1000 g/mol and decreases with functionality using measurements performed by gravimetry-axisymmetric drop-shape analysis. The nonmonotonic effect of molecular weight on CO2 solubility results from the competition between effects that reduce CO2 solubility (lower mixing entropy) and effects that increase CO2 solubility (lower ratio of hydroxyl end groups to ether backbone groups). To generalize our measurements, we modeled the CO2 solubility using a perturbed chain-statistical associating fluid theory (PC-SAFT) model, which we validated by showing that a density functional theory model based on the PC-SAFT free energy accurately predicted the interfacial tension.

Substituted Poly(Vinylphosphonate) Coatings of Magnetite Nanoparticles and Clusters

Magnetite nanoparticles and clusters of nanoparticles have been of Increasing scientific interest in the past decades. In order to prepare nanoparticles and clusters that are stable in suspension, different coatings have been used. Phosphates and phosphonates are a preferred anchoring group for the coating of magnetite nanomaterials. However, poly(vinylphosphonates) have rarely been used as a coating agent for any nanoparticles. Here, poly(methylvinylphosphonate) and other substituted polyvinylphosphonates are described as new coatings for magnetite nanoparticles and clusters. They show great stability in aqueous suspension. This is also the first time phosphonate-coated magnetite clusters have been synthesized in a one-pot polyol reaction. The coated magnetite nanoparticles and clusters have been characterized by TEM, EDX, FTIR, magnetization measurement, XRD as well as XPS. It has been shown that substituted vinylphosphonates can be easily synthesized in one-step procedures and as a polymeric coating can imbue important properties such as stability in suspension, tight binding to the particle surface, the ability to be further functionalized or to tightly adsorb metal ions. For the synthesis of magnetite clusters the cluster formation, polymerization and coating are done in a one-pot reaction and the resulting magnetite clusters show a higher amount of phosphonate coating than with a three-step procedure including a ligand exchange.

Optical Active Thermal Stable Nanocomposites Using Polybutadiene-Based Polyurethane and Graphene Quantum Dot-MnO2

Synthesis and characterization of new polybutadiene-based polyurethane, graphene quantum dot-MnO2 nanoparticles, and relative nanocomposites were set as the aim of current artwork. For this purpose, a one-pot polymerization approach was employed in preparation of polyurethane through the reaction of amine polyol and toluene diisocyanate (TDI) in presence of DBTDL catalyst. Nanocomposites were synthesized using 1 to 3 incorporation percent of graphene quantum dot-MnO2 nanoparticles in polymer matrix. 1H-NMR and FT-IR spectroscopies confirmed successful synthesis of reaction products including graphene quantum dot-MnO2, polyurethane, and nanocomposites. UV-vis and PL spectrophotometry techniques were applied for achieving optical information of samples. Optical properties of nanocomposites were reserved properly with no great quenching. Thermal stabilities, degradation rates, and thermal characteristics of polyurethane and nanocomposites were investigated using TGA/DTG and DSC analysis. Thermal stability showed direct relationship to nanoparticle content, and 3%wt nanocomposite showed improved thermal behaviour in comparison with pure PU. SEM, XRD, and AFM techniques proved successful nanocomposite synthesis with detecting nanoparticle species and fine nanoparticle dispersion with improved topographic and morphologic characteristics making GQD-MnO2 polyurethane nanocomposites a good candidate for using in optical active and thermal stable coatings.

Double-shelled hybrid MgFe2O4/Fe2O3 hollow microspheres as a high-capacity anode for lithium-ion batteries

Ternary metal oxides Fe2O3 and MgFe2O4 have attracted considerable attention as lithium anode materials owing to their high theoretical capacities, environmental friendliness, and low cost; however, their rapid capacity decay and large volume expansion inhibit their lithium storage performance. Herein, we synthesize hybrid MgFe2O4/Fe2O3 hollow microspheres (MFO/FO-HS) hydrothermally, via the polyol reaction of ethylene glycol, followed by calcination at different temperatures. The surface morphology was tuned by adjusting the calcination temperature, assisted by inward and outward Ostwald ripening. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis were performed to investigate the physio-chemical properties of the prepared samples. The sample calcined at 450 °C exhibited an excellent electrochemical performance and retained a reversible capacity of 1390 mAh g−1 after 160 cycles, indicating the significant role of calcination temperature in tuning the structural and electrochemical properties of anode materials. The double-shelled hollow microspheres inhibit rapid capacity decay and prevent severe volume expansion during the electrochemical process. This work opens new paths toward constructing an electrode material with a high electrochemical performance.

New thermal-latent titanium metal catalyst using dual curing reaction for electroactive polymers

New thermal-latent metal catalyst (LPTi) was designed and synthesized based on a lauroyl peroxide and titanium. The synthetic method has facile one step reaction. LPTi structure was confirmed by FT-IR analysis. Molecular design was based on radical preparation from lauroyl peroxide moiety under the constant increased temperature as well as titanium metal catalyst property for urethane polymerization, meaning dual curing method. n-Butyl acrylate polymerization with LPTi had an exothermic peak at about 113 °C in DSC, and the crosslinking conversion was 75%. Also, in the reaction of polyol and isocyanate, the storage modulus value was 3.87 × 103 Pa in case of catalyst-free and the storage modulus value was 1.12 × 105 Pa when LPTi was added. Therefore, storage modulus increased about 30 times by the catalytic effect of LPTi.

Formation of urethane linkage using copolymers of glycidyl methacrylate, methyl methacrylate, and butyl acrylate

Polyurethanes are synthesized from the reaction of diisocyanates and polyols. Isocyanates are quite toxic which creates several complications on exposure. To avoid the usage of isocyanates, different chemistry for the synthesis of polyurethanes is used i.e. cyclic carbonate and amine chemistry. For using this chemistry, the three acrylic monomers, Glycidyl Methacrylate (GMA), Methyl Methacrylate (MMA), and Butyl Acrylate (BA) were copolymerized via solution polymerization technique, in N-methyl pyrrolidinone (NMP) as the reaction medium, and azobisisobutyronitrile (AIBN) as the initiator. The reaction was accompanied by the conversion of epoxy groups to cyclic carbonate groups, by the reaction of the epoxy group of GMA with carbon dioxide in presence of LiBr as a catalyst. The copolymer formed with epoxy and cyclic carbonate groups was cured with monomeric and polymeric diamines. Thin films of 50 µm were applied on steel panels and baked at 130 °C for 40 min. The mechanical optical and chemical resistance properties of the film were studied. The FTIR reports confirmed the polymerization, carbonation, and urethane linkage formation. The cyclic carbonate peak at 1800 cm−1 and urethane linkage at 3380 cm−1 and 1720 cm−1 appeared after carbonation and curing with diamine respectively. Films properties were best observed when cured with the polymeric diamine. This method is not only isocyanate-free but also utilizes carbon dioxide, and hence is sustainable and eco-friendly.

Thermic Characteristics Of Rice Husk And Polyurethane Composite Materias As Insulation In Fish Cold Storage

&#x0D; &#x0D; &#x0D; &#x0D; The process of freezing fish always requires a cooler as a temporary storage place for fish. The ability of the storage to maintain cold temperatures is a serious problem to be considered so that the freshness of the fish can be maintained. Therefore, an appropriate technology is required to support the cold chain system so that fish quality can be maintained. The purpose of this study was to test the thermal conductivity of composite materials for fish storage insulation from a mixture of rice husks and polyurethane so that the price of the box can be reduced but still maintain the quality of the fish. The composition of the composite material was made with a volume ratio of 1:0.5, 1:1, 1:1.5, and 1:2. The thermal conductivity test of the material uses the ASTM E1225-99 standard. All test results were compared with 100% polyurethane material. The results of testing the thermal conductivity of 100% polyurethane material obtained 0.023 W/m.C. From all the test results, the material that is most likely to be applied to fish cooler box insulation is a 1:1 composition having a thermal conductivity value of 0.067W/m.C. Materials with this composition do not affect the expansion of the polyol and isocyanate reactions. This composition is the most economical to be used as insulation for fish storage boxes which can save the use of polyurethane by 50%.&#x0D; &#x0D; &#x0D; &#x0D;

Synthesis of higher carboxylic acids via reaction of polyols with CO2 and H2

Synthesis of value-added chemicals from biomass-derived polyols and CO 2 is of great importance. Herein we report a strategy to produce higher carboxylic acids by the reaction of polyol, CO 2 , and H 2 . The reaction can be efficiently accelerated by Rh catalyst in a binary solvent of ionic liquid (1-butyl-3-methylimidazolium iodide) and water, where cheap and nontoxic I 2 was used as a promoter. The reaction can occur at above 100°C. At optimal conditions, the yield of the carboxylic acids was as high as 86.4%. The catalytic mechanism is proposed based on a series of control experiments. Interestingly, the polyol could be effectively transformed into olefin intermediate at metal-free and mild conditions, which was the key to the success of this strategy. The peculiar solvent effect was also favorable to the reaction. In addition, the catalytic system was adaptable to various polyol substrates. • Higher carboxylic acids are effectively produced from polyol, CO 2 , and H 2 • The Rh/I 2 catalyst may accelerate the reaction in the ionic liquid/water solvent • The polyol is transformed into the olefin intermediate at metal-free condition • Various polyols and simulated crude glycerol could be applied as substrates The accumulation of CO 2 in the environment and the over-reliance on dwindling fossil fuel may cause disastrous consequences. In mitigating these challenges, chemical utilization of CO 2 and biomass-derived polyols have aroused extensive interest among scientists all over the world. As a clean reductant, H 2 can be produced from water by renewable energy, such as wind, hydro, and solar energy. Higher carboxylic acids are basic and very useful chemicals. Synthesis of higher carboxylic acids from CO 2 usually needs expensive or air/water-sensitive substrates, such as organometallic reagents, organic halides, and/or unsaturated hydrocarbons. In addition, metallic reducing agents and/or silanes are often needed to drive the reactions. In this report, we developed a method to efficiently produce higher carboxylic acids via reaction of CO 2 , biomass-derived polyols, and H 2 . The catalytic system was recyclable and may apply to various polyols and simulated crude glycerol. Higher carboxylic acids are efficiently synthesized by the reaction of biomass-derived polyols, CO 2 , and H 2 accelerated by a Rh catalyst with cheap and nontoxic I 2 promoter in a binary solvent of 1-butyl-3-methylimidazolium iodide and water. The catalytic system may apply to various polyol substrates and simulated crude glycerol.

S-doped TiO2 spindles wrapped by graphene with high exposed {001} faces and intimate contact

A new composite of intimately contacted S-doped TiO2 spindles/graphene (with S/Ti ratio of 1/3, denoted as S–TiO2@GP) was synthesized via a simple self-developed one-pot vapor-thermal method. As the water needed for the hydrolysis of Titanium (IV) tetraisopropanolate (TIP) was supplied by the etherification reaction of polyols, the hydrolysis rate was largely slowed down, which ensured TiO2 nucleation and growth on the GP surface and achieved close contact. The as-obtained S–TiO2@GP includes TiO2 spindles with six {001}/{010}/{100} facets, proving its high exposure of {001} active facets and potential photocatalytic applications. Its photocatalytic performance was evaluated by degrading methylene blue. Compared to the samples with different S-doping, S–TiO2@GP shows much better photocatalytic performance. This could be attributed to its largely exposed high-active {001} faces, enhanced visible-light-absorption, higher specific surface area and the effective electron-hole separation achieved via photogenerated electron transfer from excited TiO2 to GP, all of which were studied using HRTEM, UV–vis DRS, BET specific surface area, XPS and spin resonance spectra (ESR). ESR results also revealed that both ·O2- and ·OH contribute to the photocatalytic activities. This work provides a promising one-pot method for constructing intimately contacted S-doped TiO2/GP composite with high exposed {001} faces and excellent photocatalytic activities.

Natural fillers as reinforcement for closed-molded polyurethane foam plaques: Mechanical, morphological, and thermal properties

Natural fillers including cellulose, chitin, hazelnut, and eggshell are some of the most abundant bio-resources available for performance-cost-benefit applications. For this study, the aforementioned fibers were added to pure polyurethane foam and the properties were investigated based on mechanical (tensile, split tear, elongation, resilience, compression set, and hardness), thermal (thermogravimetric and differential scanning calorimetry), and morphological analyses. These natural fibers were added in wt. % of 1 %, 2.5 %, and 5 % using high shear mixing rates. The closed molded polyurethane foam was prepared using an addition reaction of polyol and isocyanate. The resulting foam composites embedded with natural fibers had uniform color distribution, indicating good fiber dispersion. 1 % fiber loading showed improvements in tensile and resiliency, whereas split tear properties decreased. Moreover, morphological results indicated uniform foaming and dispersion of fillers. This study reinforces the possibility of a more sustainable future by replacing synthetic fillers with natural fillers in industrial applications, including in the automotive, textile, construction, and other leading consumer-based industries.

Synthesis and characterization of solvent free acrylic copolymer for polyurethane coatings

Solvents play a huge role in the manufacturing of various acrylic resins due to their ability to control the molecular weight, reduce the viscosity and enhance the flow and levelling of the coatings. However, they contribute significantly to volatile organic content (VOC) which is a key parameter in the field of coatings industry. In view to minimise VOC, various polyols have been studied as reactive diluents/solvents to replace conventional solvents in acrylic polyol synthesis. In this manuscript, 1,3-propanediol oligomer, a 100 % bio-based oligomer has been used to completely replace the conventional solvent in the acrylic polyol synthesis. 1,3-propanediol not only acts as a solvent but also takes part in the curing process by reacting with polyurethane (PU) cross-linkers. To achieve the same properties as solvent based acrylic polyol resins, suitable monomers, initiators and reaction conditions were explored. Most of our designs exhibited viscosity in the range of Z6 to Z8 on Gardener scale at 25 °C. A solitary design resulted in a viscosity of Z4-Z5, which was well within our required parameters. This acrylic polyol resin based on 1,3-propanediol was cross-linked with PU cross-linkers in clear coat. The obtained film was then studied using various analytical techniques such as dynamic mechanical analyser (DMA), thermogravimetric analysis (TGA), gel permeation chromatography (GPC) and fourier transform infrared (FTIR) spectroscopy. The advantage with 1,3-propanediol based solvent free acrylic polyol resin is the reduction of VOC from 400 g/L to ∼ 160 g/L. It is observed that the coatings obtained from this acrylic polyol resin exhibited comparable performance in two component (2 K) PU coatings to that of in-house solvent borne acrylic systems having high VOCs.

Synthesis of Polyurethane from Diphenyl Methane 4,4 Diisocyanate (Mdi) Polymerization with Hydroxilated Avocado Oil Polyol

Polymerization between polyol and isocyanate compounds produces polyurethane in different forms. Polyol used in this study utilized spoiled avocado as the oil source for polyol to produce polyurethane. Avocado oil was epoxidized with formic acid (HCOOH) and H2SO4 catalyst at 40 – 45oC followed by hydrolysis reaction to produce polyol reaction. Next polyol was purified and structure confirmation was done using FT-IR spectroscopy analysis. Polyol was then reacted with diphenylmethane 4,4 diisocyanate (MDI) with ratios of (polyol : MDI) 9:1; 8:2; 7:3; 6:4; and 5:5 (v/v) in a total volume of 10 mL with open air stirring at 40 – 45oC to produce polyurethane. Characterization for the form was observed visually followed by the determination of gel content, density and structure using FT-IR spectroscopy. The results of polyol from avocado oil reacted with diphenylmethane 4,4 diisocyanate for each of the mixing ratio to produce polyurethane is gel content of 74.63% to 99.80% where the higher MDI ratio is, the higher gel content becomes. Density determination from the polyurethane produced is between 0.1341 g/cm3 to 0.7220 g/cm3. FT-IR spectrometer analysis to polyurethane produced is marked with the peaks at 3400 – 3300 cm-1, 2270 – 1940 cm-1, 1700-1600 cm-1 and 1590 – 1540 cm-1 wavelengths which are the characteristic of urethane functional groups.