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Polyols from vegetable oils can replace petroleumbased polyols in the preparation of polyurethanes and polyesters in a wide range of applications. However, previous preparation methods are either too costly, inefficient, or yield secondary alcohols, which are less reactive than the desired primary alcohols. The objectives of this study were to prepare primary soy-based polyols by a new catalytic ozonolysis process and to characterize the composition of the product mixture. In this new process, the polyols were prepared by passing ozone through a solution of soybean oil and ethylene glycol in the presence of an alkaline catalyst. Unlike conventional ozonolysis that yields aldehydes and carboxylic acids by spontaneous decomposition of the ozonide intermediates, the ozonides in our method reacted with the hydroxyl group of the glycol to form an ester linkage with a terminal hydroxy group. Statistical analysis of the product mixture indicates that the resulting polyol mixture is more uniform than the original TG mixture, having (2-hydroxy)nonanoate as the major component of the new hydroxyl functional TG. The chemical structure of the polyols produced was further characterized by iodine number and 13 C NMR and FTIR spectroscopy, which confirmed the cleavage of the double bonds, the presence of hydroxyl groups, and the formation of new ester linkages.Paper no. J10972 in JAOCS 82, 653-659 (September 2005). FIG. 3.Statistical distribution of soy polyols obtained by alkaline catalytic ozonolysis of soybean oil with ethylene glycol. N, nonanoate; P, palmitate; S, stearate.

Blends of soy protein concentrate and biodegradable polyester (Eastar Bio Copolyester, EPE) were prepared by using glycerol as a compatibilizing agent. Good miscibility was obtained only when the soy protein was initially combined with glycerol under high shear and at elevated temperatures in an extruder. Under these conditions, partial denaturing of the soy protein led to specific interactions between functional groups of the protein with the glycerol. The extrusion conditions and appropriate screw configuration were the critical factors affecting the reactivity of the protein and hence, the properties of the blends. Screws with large kneading blocks that produced high shear mixing were preferred and led to thermoplastic blends characterized by high elongation and high tensile strength. The morphology of these soy protein/polyester blends was studied by using environmental scanning electron microscopy (ESEM) and indicated good wetting of the soy protein particles within the polyester matrix. The thermal properties were studied by differential scanning calorimetry (DSC) and showed a lower degree of crystallinity and a continuous depression of the melting point of the polyester as the concentration of protein was increased. The possibility of using soy protein concentrate instead of the more expensive (higher purity) soy protein isolate in the preparation of biodegradable resins should lead to new commercial opportunities based on renewable, agricultural byproducts.

ABSTRACT:Composites with good mechanical properties were prepared from chemically modified soy oils and biofibers without additional petroleum-based polymers. These composites were prepared from maleic anhydride and epoxide functionalized soybean oils that were cured in the presence of various biofibers (e.g., kenaf, kayocell, protein grits, and solka-floc) by a flexible amine catalyst. Rigid thermosets characterized by a high-crosslink-density network and a high gel fraction were obtained. Fourier transform infrared was used to follow the cure reaction via the disappearance of the characteristic anhydride adsorptions. Composites with high tensile strength and low elongation were obtained when kenaf fibers were treated with (2-aminoethyl)-3-aminopropyl-trimethoxysilane and then added to the epoxidized/maleated soy matrix and cured with hexamethylenediamine. These biobased composites could provide inexpensive epoxy resin alternatives for a wide variety of industrial applications.

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In this study a new value-added product was developed from soybean oil for use as a chemical feedstock. The investigation and optimization of this work resulted in a fast and simple process to maleate soybean oil. An anhydride functionality was introduced into soybean oil through a free radical-initiated maleation. Two initiators were evaluated, 2,5-bis(tertbutylperoxy)-2,5-dimethylhexane peroxide and di-tert-butyl peroxide. The effects of reaction time, initiator concentration, maleic anhydride concentration, and reaction temperature were investigated. The maleated soybean oil was characterized using acid value, iodine value, and FTIR spectroscopy. The acid value was directly related to the initial concentration of maleic anhydride, whereas the concentration and type of initiator had little effect on the acid value. The peroxide-initiated functionalization of soybean oil with maleic anhydride in a closed vessel at elevated pressure and temperature was found to proceed by a Diels-Alder mechanism.Paper no. J10942 in JAOCS 82, 189-194 (March 2005). KEY WORDS:Free radical initiation, maleation, maleic anhydride, process, soybean oil.As the demand for petroleum exceeds production, alternative feedstocks must be found. Agriculturally based chemicals are one of the most attractive alternatives because they are environmentally friendly chemical feedstocks and offer a sustainable source of development. In previous work, we have reported on the rationale, design, and engineering of biobased materials (1,2). One potential agricultural feedstock is soybean oil (SO), which is a mixture of TG containing long-chain FA. Typically, SO contains 4.3-4.6 double bonds per mole depending on the origin of the seed. The presence of unsaturation allows for chemical modifications through specific reactions with these double bonds and the introduction of reactive carbonyl functional groups. There is a great deal of literature on the functionalization of vegetable oils using maleic anhydride (MA) to enhance their reactivity. Morrel and Samuels (3) studied the reaction between MA and conjugated oil systems using oils from china wood and oiticica containing FA with conjugated double bonds. The reaction was found to follow a typical Diels-Alder addition. Root (4) investigated the functionalization of SO with MA and described the use of benzoyl peroxide in the maleation reaction.He concluded that the use of benzoyl peroxide as a catalyst was advantageous, as it allowed the reaction to proceed at a lower reaction temperature of 110°C as compared with 160-190°C when benzoyl peroxide was not used. Root hypothesized that the presence of a peroxide leads to electron delocalization, resulting in conjugation of the double bonds within the unsaturated FA in the SO to form a conjugated system, as shown in Figure 1. However, the mechanism of MA addition to SO and the products of this reaction are still ill defined and are the subject of a great deal of debate in the literature. Clocker (5) postulated a cyclobutane structure for oleic acid adducts. Bickf...

The moisture resistance of Kraft paper was greatly improved when it was coated with silylated soybean oil that was cured via silanol condensation. This moisture barrier coating was prepared from LowSat® Soybean oil that was grafted with vinyltrimethoxysilane (VTMS) using a relatively simple process based on the "Ene reaction". The viscosity of the resulting oil was unaffected by the silylation reaction and remained low (32 cPs). Thus, the paper coating process required no solvent, additional diluent or the need to emulsify the oil which provided a convenient onecomponent cure system. Dibutyltin dilaurate (DBTDL) was found to be an effective condensation catalyst and under optimal conditions complete cure was achieved in a short period of time. The cure rate was a function of the catalyst concentration, available water and the temperature. Initially, Kraft papers were coated with the silylated soybean oil in the lab and this process was followed by a pilot scale-up using a commercial gravure roll coater. Cobb values and water vapor transmission rate indicated the cured coating provided a good barrier coating. Scanning electron microscopy (SEM) images of the coated paper confirmed a uniform coating with good adhesion of the coating material to the paper.