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Thermal conductivity (λ) of a rigid polyurethane (PU) foam plays a vital role in determining the performance of thermal insulation. To accurately predict this property for a given recipe in a few seconds is the first step towards striking a balance between compressive strength, λ, and more properties of a foam product in industrial applications during formulation. What experimentally observed from PU closed-cell foams made from PAPI-27 Polymeric Methylene Diphenyl Diisocyanate (PMDI), Voranol 360, and n-pentane were: (1) foam shrinkage and even collapse occurred on both low (typically less than 0.9) and ultra-high (close to 2.0) indexes of isocyanate (IA); (2) to achieve the lowest λ for the best thermal insulation, it was suggested to use the highest IA without any foam shrinkage, the fastest stirring rate under safety, and the least physical blowing agent (PBA) until a sharp turn in the trend of λ; (3) there was a definite link between foam density (ρf), closed cell content (ccc), and λ: (a) a low λ requested a high ρf and ccc (b) a denser foam could be achieved by at least three ways. Increasing the agitation rate had a limit, above which the change in density became insignificant. However, a higher IA and reducing the amount of PBA had always been linear with ρf. (c) ρf was the cornerstone of ccc. In low ρf range, a growth of density gave rise to a distinct improvement of ccc, beyond which ccc reached a plateau for any higher density. The foam thermal conductivity during polymerization was successfully simulated by Matlab with 0.0157 % deviation. λ was initially dominated by the contribution from the resin mixture until the gel reaction time. Then, the dominant was shifted to the contribution by the gas component. The magnitude of thermal radiation was rather low throughout the reaction.

Traditional engineering textbooks are substantially limited by approaches relying on analytical solutions where most of the applications are described by differential equations without simple analy...

Online quizzes with feedback and retake options can be effective as a remedial learning strategy in a curriculum with sequential courses that rely on prerequisites. Use of groups of two to three students on these quizzes facilitates the learning process by creating an environment where students share their knowledge and understanding. Group activities can extend to sharing and building upon the students’ strategies for locating and using free online learning resources. This paper is on methods of preparing online quizzes for remedial learning including structures of questions suitable for remedial learning and approaches to attain analysis and evaluation learning levels for a course in reaction engineering.

Polymers derived from plant oils have attracted major commercial interest and significant attention in scientific research because of the availability, biodegradability, and unique properties of triglycerides. Triglycerides rich in unsaturated fatty acids, such as soybean oil (SBO), are particularly susceptible to chemical modification for desired polymeric materials. Soy-based polyols are important industrial prepolymeric materials that use renewable resources; and can be produced or derived through different processing routes. This review paper discusses previous and recent researches about chemical and biochemical polymerization processes to produce soy-based polyols as prepolymers for the production of polyurethane materials in the form of foams (rigid or flexible) and elastomers. The central goal of these research fields is to find effective reaction routes to increase both equivalent weight and hydroxyl functionality of soy-based polyols while taking into consideration the simplicity and economics of these processes.

For a highly exothermic reaction, heat capacity is a critical determinant of temperature profile which impacts temperature-dependent variables such as reaction rate constants, heat of reaction, viscosity, and diffusivity. In the case of polymer-forming reactions: literally hundreds of oligomers can be present at any time, heat capacities are typically not available for most of these oligomeric monomers. The group contribution method emerges as one of the few viable approaches to make an estimate of heat capacities being a salient intermediate step toward the objective of simulating polyurethane reaction process. Based on compiled literature and supplemental DSC data, Missernard’s group contribution model was revised with alternative values to those suggested by literature and accessorial parameters for the following functional groups: a) isocyanate, b) six carbon sugar ring, c) aromatic benzene ring, and d) double-bonded oxygen of an ester to estimate heat capacities from 25 °C to 120 °C for alcohols and isocyanate present in the urethane-forming reactions. Modeling performance showed a good agreement with an overall 1.59 per cent deviation. It was also observed that the alcohol heat capacity generally decreased with the rise of molecular weight.

The large increase in viscosity during thermoset reactions leads to reduced frequencies of reacting moiety collisions with respective reduced reaction rates. Molecular diffusion substantially ends after the gel point; however, reactions continue after the gel point through mechanisms involving local movement (and reacting moiety contact) of polymer sections/branches which is referred to as intra-molecular movement. The impact of inter- and intra-molecular movements was simulated for polyurethane reactions to better understand the impact of mass transfer on polymerization reactions. Inter-molecular reaction mechanisms are dominant prior to the gel point, and intra-molecular mechanisms are dominant after the gel point. Representing the Arrhenius pre-exponential factor as a sum of a viscosity-dependent term and a viscosity-independent term was identified as the most efficient method to model this phenomenon. Good agreement of simulation results for reaction temperature, foam height, and viscosity profile with the experimental data were obtained.

The simulation of polymer-forming reactions can be a powerful tool to reduce the time and cost of developing new polymer formulations; formulations that can be potentially both more sustainable and less costly. A critical aspect of advancing such simulations is the reduction in the number of fitted parameters, and more specifically, the identification of fundamentally-correct parameters that can be applied to a range of reactions as opposed to parameters specific to each reaction. This paper presents an innovative approach focusing on the frequency factor of the Arrhenius equation resulting in insight to how this frequency factor is a characterization of mass transfer that can be broadly applied to a range of similar reactions. The result is a reduction in the number of fitted parameters needed for simulation and providing a more fundamental, efficient, and robust method to simulate thermoset polymerization reactions. Impacts of mass transfer limitations due to the large increase of resin viscosities during thermoset polymer reactions were reflected in the frequency (pre-exponential) factor of Arrhenius equation. By representing the frequency factor as the sum of viscosity-dependent and a viscosity-independent terms to account the impact of inter- and intra-molecular diffusion/movement of the reacting moieties in the resin, the same pre-exponential factor was able to be used for catalytic and non-catalytic paths. Impacts of catalysts were reflected in lower activation energies. Temperature profiles of urethane gel reactions were used to characterize the reactivities of different polyols based on the fractional content of primary (versus secondary) hydroxyl moieties. This approach the simulation results of reaction temperature show good agreement with the experimental data.

Detailed modeling and simulation of the reaction of alcohol and isocyanate moieties to form urethane have provided a reason to question conventional opinions that this is a step-growth polymerization process. In particular, industrial formulations are dominated by catalytic mechanisms, and these chain mechanisms can change the polymer growth mechanism. This paper's research evaluates experimental data of reaction temperature and resin viscosity of urethane gel reactions that substantiate a chain-growth mechanism. One of the artifacts of a chain-growth mechanism is the rapid appearance of relatively large molecules that reduce gel point times earlier with step-growth mechanisms.

Flow-permeable separators underwent surface modification, and their performances were evaluated to determine the impact of an ion-exchange coating on the electrochemical properties of sandwich diffusion batteries. A zinc–alkaline system was used to evaluate this performance at high discharge rates and diffusion overpotentials across the separator. An alkaline-resistant anion-exchange polyelectrolyte was synthesized based on a quaternary ammonia polysulfone system to utilize the coated separators for faster ion and counterion transport, and the obtained functionalized separators were compared with stationary inert porous separators. Accordingly, the discharge behavior of primary battery systems for both inactive and functionalized separators was introduced. According to discharge profiles, the practical voltage range, specific capacity, and utilization of active materials were improved, and ionic conduction was enhanced and verified by electrochemical impedance spectroscopy. Different commercial filter pap...

A series of over 30 differential equations were solved to model experimental data on urethane foam formation. Methyl formate and C5–C6 hydrocarbons were used as physical blowing agents, and water was used as a chemical blowing agent. The rate of evaporation of the physical blowing agents was estimated using an overall mass-transfer coefficient times the difference in activity in the gas phase inside the bubbles and in the resin walls of the bubbles. The rate of CO2 diffusion was expressed as the overall mass-transfer coefficient times the rate of CO2 generation. The overall mass-transfer coefficient was found to decrease to near zero as the gel point of the resin was approached. Only one fitted parameter was used for the overall mass-transfer calculation for all blowing agents. The simulation results for foam height agree with the experimental data. Bubble growth and bubble pressure were simulated for the first time as compared to the available literature.

Computational calculations were performed on urethane-forming reactions using Gaussian 09 software (i.e. molecular modeling) toward the goal of providing thermodynamic parameters. Total electronic and thermal enthalpies and zero-point vibrational energies of reactants and products were computed by the software and then reaction enthalpies were calculated based on these results. The location of functional groups has the most significant impact on reaction enthalpies while molecular size, chain length and solvent effect have relatively less impact on reaction enthalpies. By comparison to new experimental studies and values reported in literature, better-informed recommendations on which values of reaction enthalpies to use for urethane foam process simulation were provided. The utility of computational chemistry results succeeded in being an enabling technology to improve foam process simulation. In turn, simulation of urethane-forming reactions is useful to bridge the gap between fundamental computational chemistry calculations and practical applications. POLYM. ENG. SCI., 55:1420–1428, 2015. © 2015 Society of Plastics Engineers

The reaction of polyol and isocyanate monomers to form polyurethanes is commonly presented in reaction chemistry that implies a step-growth mechanism for the polymerization. However, viscosity versus temperature profiles of both experimental studies and gel-forming simulation studies indicate that the degree of polymerization resulting from the reactions varies considerably from reactions with catalysts compared with those without catalysts. An extension of a simulation based solely on step-growth mechanisms to simulations that include chain growth via an active catalytic complex provides viscosity and temperature profiles that are consistent with the range of experimental data. The results indicate that as catalytic mechanisms dominate the kinetics chain growth mechanisms also overwhelm step growth mechanisms. Based on this mechanism, the choice of catalysts can impact both the rate of reaction and degree of polymerization length; both being of high importance in engineering urethane foams.

One of the obstacles to displacing petroleum-based polyols with soy-based polyols in rigid urethane foam formulations is foam shrinkage, especially at displacements greater than 50%. The shrinkage is a result of partial vacuums forming in the closed-cell foam as reaction temperatures dissipate. It was hypothesized that the shrinkage was in part due to inadequate curing of the foam which was due to lower maximum-attained temperatures during the near-adiabatic foaming process. Foam formulation studies were performed to evaluate the correlation of peak temperature foam shrinkage. Two approaches were evaluated to increase peak temperatures: (a) preheating of the monomers prior to reaction and (b) use of bio-based glycerol as a co-reagent to increase the mixture hydroxyl number and respective maximum temperatures. The results show that as the maximum reaction temperature increases, foam shrinkage decreases. Both preheating and use of a glycerol co-reagent were effective for increasing peak temperatures and decreasing shrinkage. Experimental results were supplemented with a simulation of the foaming process to better understand the fundamental phenomena and to evaluate the effectiveness of the simulation to evaluate approaches to better utilize bio-based monomers in thermoset polymers.

Polyol oligomers formed from reactions of mono-, di-, and triethylene glycols with epoxidized soybean oil were synthesized and the reaction conversions were modeled. The data verified the effectiveness of a model that is based on the simultaneous solution of eight ordinary differential equations. In addition, the data demonstrated that di- and triethylene glycols produced lower viscosity oligomers than monoethylene glycol. Since the model is fundamentally based, it provides insight into the reaction mechanisms and allows for simulation of reaction conditions with reasonable extrapolation. Within the accuracy of the data, the reaction rate coefficients for all alcohol and epoxy moieties were equal, independent of the molecule to which they were attached—reaction rates varied based only on temperature and dilution of reacting moieties. The model provides an effective means to simulating concentration, viscosity, and temperature profiles including estimates of degrees of polymerization, which are dependent o...

A solid-phase ion conductivity parameter has been added to the separator of a porous electrode theory description of a convection battery performance to increase the accuracy of this model. With the addition of the ion conductivity parameter, the variances between the model and experimental data have been reduced by 80–85% in both the convection cell and the diffusion cell. The parameter is fundamentally consistent with solid-phase mechanisms by which ions can transport through separators in parallel with liquid-phase transport, and the improved modeling results substantiate the importance of solid or surface ion transport mechanisms at high current fluxes. Modeling was supplemented with dimensionless analysis to lump fundamental parameters that are inherently coupled in the underlying equations. From this analysis, a global parameter has been developed describing the ratio of convective charge transfer to diffusive charge transfer that characterizes the transition from diffusive to convective cell behavior. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3784–3791, 2014

A MATLAB program was developed to simulate polyurethane foaming reaction. Key reactions (including isocyanate–polyol and isocyanate–water) and dozens of primary side reactions were taken consideration into the simulation of polymerization. The model tracks reaction rates, component concentration profiles and the temperature profile for the reactions under different conditions respect to different catalyst types, amount of catalyst loading, reaction temperature and the reactivities of the monomers with each other. Tin based catalysts and amine based catalysts were applied into gel and foam recipes separately to evaluate the impact of each catalyst on both gel and blow reactions. The model predicts performances of diverse foam recipes and can be effective for “sensitivity studies” useful in designing form formulations. The simulations have been validated for estimating catalyst loadings, identifying the tradeoff between higher catalyst loadings versus preheating of reagents, and providing insight into fundamental mechanisms/reactions.

Based on experimental viscosity data collected from single material and binary system mixtures, a group contribution method was introduced to estimate viscosities of a range of polyol oligomers and urethane polymers at temperatures from 25 to 150°C. Use of mixture rules then extends the estimation method to multi-component reacting systems. Mixture viscosity data were used to determine the Gibbs free energy (G) in the Grundberg-Nissan equation which can be used to estimate mixture viscosities with correction for some non-idealities. The resulting model is able to accurately predict mixture viscosities based on binary interaction. The goal of this work is to estimate the viscosities of urethane-forming reactions; accurate viscosity information is critical as an intermediate step to predict how successful a foam formulation would be and to ultimately estimate the final physical properties of the foam.

A MATLAB model based on the simultaneous solution of several differential equations was developed to include the impact of catalyst loading for the reactions and physical processes of a urethane box foaming process. Experiments with different amounts of catalyst loading were conducted to fit the model parameters for this thermoset polymerization. Rate constants for the polyurethane foaming reaction were determined by polyol types, catalyst types and reaction temperatures. By combining these factors polyurethane reaction rates during whole foaming process can be calculated in this model and the model can be used to predict the performance of foams which have multiple combinations of isocyanate, polyols, catalysts, chemical blowing agents, and physical blowing agents in recipes when parameters on pure component (e.g. single polyol) performance are behavior.

The effect of carbon surface area on capacity is investigated in cathodes for lithium sulfur batteries. Carbon additives help overcome the low electrical conductivity of sulfur. Cathodes were prepared at 30 wt% sulfur on different activated carbons having unloaded BET surface areas of 1200–3200 m2/g. Sulfur utilization ranged from 33% to 83% of the theoretical capacity (1672 mAh/g) with a strong correlation to the accessible pore volumes having pore widths between 1 and 5 nm. Additionally, cathodes prepared at 12.5–68 wt% on an activated carbon having unloaded BET surface area of 3200 m2/g showed excessive sulfur loading provided little additional capacity.

A model based on about a dozen fundamental differential equations is used to evaluate and simulate the urethane reactions and physical processes of urethane box foaming. This work focuses on quantitative modeling of foam density for foams using water and physical blowing agents. The final densities of foams range from 30 to 90% of the density as projected with full utilization of the blowing agent. The primary sources of inefficient use of blowing agent are loss of the physical blowing during open-air mixing and degassing—basically, physical blowing agents with boiling points between 25 and 80°C will evaporate and experience cell rupture in box foams. This loss of blowing agent would not apply to in-line mixers used for commercial production and should be taken into account with scaling up box or cup foams commercial processes. POLYM. ENG. SCI., 54:1503–1511, 2014. © 2013 Society of Plastics Engineers

A theoretical model was developed to simulate the polyurethane foaming process for a rigid foam. In the model, multiple ordinary differential equations were solved by MATLAB and the model was able to predict temperature profiles by inputting foam recipe information. This initial study on foam modeling focusses on reaction kinetic parameters that were fitted to experimental temperature data as a function of time. The modeling was able to accurately model temperature profiles of single-polyol polyurethane formulations and was able to accurately predict temperature profiles of mixtures based on pure component kinetic parameters. A primary goal of this work is to expedite the ability to develop new foam formulations by simulation—especially for incorporation of new bio-based polyols into formulations. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1131-1138, 2013

Porous electrode theory was used to model performance of the convection battery using lithium iron-phosphate chemistry. The model results and underlying equations were able to quantify and extend previous interpretations of laboratory validation studies. These analyses substantiated the following conclusions on the performance of the convection battery: (a) flow in the convection battery can reduce concentration overpotentials by 99.9%, (b) both the ionic and electron conductivities of solid phases can have a major impact on convection battery performance, and (c) the solid-phase ionic conductivity of a porous separator is an important design parameter and is not considered by porous electrode theory as published to date. In view of the ability of the convection battery to overcome both bulk diffusion and liquid-phase effective conductivity limitations; the convection battery has an unprecedented potential to redefine the performance of large batteries. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2833–2842, 2013

One of the best applications of wind and solar power is in remote locations. Sufficient data and reports are available to estimate benchmark costs for wind applications, and these benchmark costs show that these renewable energy applications tend to be more costly than grid power. Also, backup power is needed and can cost more than the wind or solar systems. However, there are great opportunities and paths forward that will lead to a resurgence of off-grid power in the United States and a dominance of off-grid power in countries where an electrical grid structure is not already in place

Man has developed many ways to convert stored energy into the most useful forms of mechanical and electrical energies. This chapter reviews the basic approaches of performing these conversions.

Heating, ventilation, and air conditioning (HVAC) consume a large fraction of the energy consumed in the United States, second only to transportation as a category of energy consumption. Plans in sustainable energy must include sustainable HVAC. As with transportation fuels, large strides in sustainability in HVAC can be made by an increased reliance on electrical power for these demands and coordination to allow for peak load shifting in grid power.

In selecting energy options, there are obvious factors such as the cost of the energy feedstock. There are also factors that are not as obvious such as the impact of tax infrastructures and the time it takes to realize the return on an investment. This chapter covers the underlying factors that impact investments and evaluates how artificial barriers may be overcome in the future.

Perceptions of nuclear power tend to be dominated by concerns on safety and waste management, and the key to understanding how these can be handled with security and sustainability is a fundamental understanding of nuclear processes and materials. This chapter traverses the chapters from atomic-level nuclear changes, to reactor options, and finally the handling of spent nuclear fuel. A comprehensive understanding leads to comprehensive solutions that are sustainable.

In Chapter 1, the sources and utilization of energy are put in perspective with emphasis on several events in history that either have shaped our current energy infrastructure or reveal what is possible. The Standard oil monopoly provides a good example of how powerful energy industries can become. World War II provides an example of what can be achieved in the way of advances in technology when such advances become a national priority. More recently, Tesla Motors marketing and oil fracking technology are providing stability and options in the energy sector in ways that were not predictable 10 years earlier.

Arriving at great strategies for sustainable infrastructure requires both the use and understanding of those methods used by industry to make decisions and the use of advanced comparative economic analyses. Good levelized cost methods are available to compare the cost of alternatives; these methods need to be more widely used and the critical comparison of paths to sustainability need to be considered. In addition, better methods of economic analysis need to be developed and applied. All this is possible and can be of great benefit.

All energy on earth is connected from a common source in the hydrogen atom and the history of that energy as stored in atoms and the chemical bonds of both fossil fuels and vegetation. A history of this energy puts issues in perspective—whether making ethanol or operating a nuclear reactor, man is only exercising control over processes that have been occurring for hundreds of millions of years. Stockpiles of fossil and nuclear fuels are a result of this cosmic history. An assessment of nature’s energy stockpiles reveals that there is abundant energy; the key to mankind’s prosperity is both technology and the ability to implement that technology on a timely basis. Good strategies are paramount.

Electricity brings with it diversity in energy source. Diversity brings with it stability in supply and price as well as options for sustainability. To the advantage of electricity, it is able to meet most of the energy demands of society, including displacing of much of jet travel with a new mode of transportation.

Use of electrical power for vehicles brings with it stability in prices and supply as well as national security. A primary obstacle to displacing larger amounts of liquid fuels with electrical power in the past has been the high price of batteries. For the first time in history, the path to lower cost batteries and ultimate sustainable and major gains of battery-powered vehicles seems inevitable. In addition, there are new approaches to direct use of grid power for transportation.

The convection battery forces flow of electrolyte through the cathode, anode, and the separator between them, unlike a flow battery where electrolyte cannot cross the separator. The goal is to increase ion fluxes (A/cm2) to realize the benefit of thicker electrodes, lower cost batteries, and reduced charge times. A pump that circulates electrolyte was turned off to create a diffusion control to which the performance of the convection battery was compared. Based on performance at

Highly nanoporous carbon with surface areas in excess of 3,000 m2/g can be produced via potassium hydroxide (KOH) activation of a high surface area (1,150 m2/g) carbon intermediate. These materials have exhibited methane storage capabilities in excess of 20 wt % at ambient temperature with interest toward commercial production. In preparation for commercial production, detailed mass balances are needed to quantify yield and waste streams, understand the propensity to recycle the KOH, and to provide a benchmark for further optimization. Analytical processes used to evaluate produced carbon performance are detailed in addition to a mass balance on the reaction of KOH with carbon and a KOH balance. Carbon balances revealed that increasing activation time and activation temperature produce lower yields of carbon.

This study investigated the physical properties of water-blown rigid polyurethane (PU) foams made from VORANOL®490 (petroleum-based polyether polyol) mixed with 0–50% high viscosity (13,000–31,000 cP at 22°C) soy-polyols. The density of these foams decreased as the soy-polyol percentage increased. The compressive strength decreased, decreased and then increased, or remained unchanged and then increased with increasing soy-polyol percentage depending on the viscosity of the soy-polyol. Foams made from high viscosity (21,000–31,000 cP) soy-polyols exhibited similar or superior density-compressive strength properties to the control foam made from 100% VORNAOL® 490. The thermal conductivity of foams containing soy-polyols was slightly higher than the control foam. The maximal foaming temperatures of foams slightly decreased with increasing soy-polyol percentage. Micrographs of foams showed that they had many cells in the shape of sphere or polyhedra. With increasing soy-polyol percentage, the cell size decreased, and the cell number increased. Based on the analysis of isocyanate content and compressive strength of foams, it was concluded that rigid PU foams could be made by replacing 50% petroleum-based polyol with a high viscosity soy-polyol resulting in a 30% reduction in the isocyanate content. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A zinc/alkaline/manganese dioxide packed-bed electrode flow battery was used to evaluate using granular materials with ionic activity as separating materials between electrodes, increasing the separation distance between electrodes, while using separating materials, and reversing the electrolyte flow direction through the flow battery. Results indicate that materials with more ionic activity (ion exchange resins) perform better than materials with limited ionic activity (stainless steel). Among the more ionically active materials, the basic material out-performed the acidic material with an anode-to-cathode flow regime at low current draw. The best performance was obtained using ALL-CRAFT 4K-activated carbon as separation material. The use of an ionically active separation material reduced the difference in cell performance between 2.22 and 5.40 cm of separation by 56%. Although expected to be an important parameter for packed-bed electrode flow battery, the electrolyte flow direction did not produce a discernable difference in performance using the low current draw of these studies.

A zinc-alkaline flow cell was used to validate a new type of flow battery in which all reagents and products remain as solids on the electrodes. In every case, flow of electrolyte reduced overpotential losses when compared with operation without electrolyte flow. Large separation distances between the electrodes resulting from larger sections of separating tubing led to increased overpotential losses. A mass transfer mechanism is proposed that substantiates increasing overpotential with increasing electrode separation distances. Based on this mechanism, it was hypothesized that ion exchange packing would reduce the overpotential losses; this hypothesis was experimentally validated. © 2010 American Institute of Chemical Engineers AIChE J, 2011

To explore the potential of isocyanate usage reduction, water-blown rigid polyurethane foams were made by replacing 0, 20, and 50% of Voranoll® 490 in the B-side of the foam formulation by epoxidized soybean oil (ESBO) with an isocyanate index ranging from 50 to 110. The compressive strength, density, and thermal conductivity of foams were measured. The foam surface temperature was monitored before and throughout the foaming reaction as an indirect indication of the foaming temperature. Increasing ESBO replacement and/or decreasing isocyanate index decreased the foam's compressive strength. The density of the foam decreased while decreasing the isocyanate index to 60. Further decrease in isocyanate index resulted in foam shrinkage causing a sharp increase in the foam density. The thermal conductivity of foams increased while decreasing the isocyanate index and increasing the ESBO replacement. Mathematical models for predicting rigid polyurethane foam density, compressive strength, and thermal conductivity were established and validated. Similar to compressive strength, the foaming temperature decreased while decreasing the isocyanate index and increasing the ESBO replacement. Because of the lower reactivity of ESBO with isocyanate, the rate of foaming temperature decrease with decreasing isocyanate index was in the order of 0% > 20% > 50% ESBO replacement. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

A screening study was conducted to identify a catalyst that promotes epoxy ring opening of full epoxidized soybean oil (ESBO) avoiding side reactions at low concentration and temperature. Six catalysts different catalyst: formic acid, phosphoric acid, POLYCAT® 5, p-toluenesulfonic acid monohydrate, POLYCAT® SA-1, and DABCO® BL17 were evaluated in terms of acid number, oxirane oxygen content, and color analyses. p-Toluenesulfonic acid shows a particular behavior that promotes the reaction resulting in a maximum oxirane oxygen content reduction; low acid number and color index compare to the others catalyst. To create an alkoxy hydroxy ESBO molecule, ESBO was combined with methanol and ethylene glycol using 0.5% by wt of p-toluenesulfonic acid at 130, 150, and 170°C for different reaction times. Optimal conditions for oxirane ring opening by alcoholysis reaction were determined varying temperatures and reaction times. FTIR spectrum confirmed the emergence of hydroxyl groups in the alkoxy hydroxy ESBO polyol sample. The polyol sample G was characterized in terms of its hydroxyl number and its potential of replacing up from 50–100% of the petroleum-based polyol in waterborne rigid polyurethane foam application. All polyurethanes foams were evaluated to determine their thermal conductivity, density, and compressive strength properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The study investigated an approach to incorporate modified epoxidized soy-based vegetable oil polyol as a replacement for petroleum-based polyether polyol and to substantially reduce the isocyanate loading in the rigid foam formulation. Noncatalytic polymerization of epoxidized bodied soybean oil and ethylene glycol (EG) was carried out in a closed batch reaction. Cleavage of the oxirane rings and hydroxyl group attachment at optimum conditions provided the desired polyol products. The polyols were characterized based on its hydroxyl numbers, acidity, viscosity, iodine number, and Gardner color index for quality purposes. Reactions of oxirane ring and EG were verified by spectroscopic FTIR. Crosslinking performance was evaluated by extractability analysis on the polyurethane (PU) elastomer wafers. Rigid foaming performed at 50 and 75% petroleum-based polyether polyol replacements have shown excellent thermoinsulating and mechanical properties compared with epoxidized soybean oil (ESBO) alone or petroleum-based polyether polyol alone. A reduction of up to 8% of the polymeric diphenylmethane diisocyanate was achieved using the synthesized ESBO-EG-based polyols. A higher average functionality polyol is key component to the reduction of isocyanate in PU synthesis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

In the absence of polymerization, soy-based polyols tend to have inadequate hydroxyl equivalent molecular weights for many critical urethane applications. In this article, the polymerization (bodying) of soybean oil is presented as an effective method to increase the molecular weight of soy-based polyols. When bodying is combined with reaction steps for alcohol addition and acid reduction, soy-based polyols suitable for urethane applications can be synthesized. Two different heat-polymerization approaches, catalyzed- and noncatalyzed-bodied soybean oil (BSBO) were evaluated in continuous and batch processing. The catalyzed-BSBO has lower iodine numbers and high viscosities than the noncatalyzed-BSBO. This approach represents one of the least-costly means to increase the hydroxyl equivalent weights of soy-based polyols. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

An acylglycerol-based molecule was synthesized by the thermal polymerization (bodying) of soybean oil followed by transesterification with glycerol. Transesterification with glycerol at temperatures greater than 200°C provided the desired polyol prepolymers. The extent of bodying and quantity of glycerol added during the transesterification provided tunability of the polyol molecular weight and functionality. The hydroxyl numbers, acidity, and viscosity of the polyols were characterized. The polyols were evaluated in elastomers and rigid foams. Extractability analyses were performed on the polyurethane elastomer wafers to evaluate crosslinking. Rigid foaming results for the processed soy-based polyol showed excellent physicochemical properties suggesting comparability with a petroleum-based polyether polyol. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Glycerol has become readily available from biodiesel industry. High functionality and relatively low price make it a potential building block to produce value-added derivatives such as acrolein. In this study, low-pressure packed-bed gas-phase dehydration of glycerol was investigated in presence of various solid acid catalysts, including H3PO4/activated carbon catalyst. Dehydration mechanism over H3PO4/activated carbon catalyst was validated. In the presence of H3PO4/activated carbon catalyst, yield of acroelin (66.8%) and selectivity to acrolein (84.0%) were achieved at the temperature of 260 °C and the pressure of 0.85 bar.