E. J. Saggese

Urethane foams from animal fats. IV. Rigid foams from epoxidized glycerides

Liquid polyols have been prepared from epoxidized glyceryl trioleate, glyceryl monooleate, lard oil, neatsfoot oil, and soybean oil by hydration with 24% fluoboric acid. Upon adjustment of the equivalent weight to 100 with triisopropanolamine, the polyols were foamed by reaction with a prepolymer made from oxypropylated sorbitol and tolylene diisocyanate. The resulting rigid foams had densities between 1.66 and 2.34 lbs/ft3 and compressive strengths ranging from 23 to 39 psi (10% compression).The same polyols were used in one-step systems with PAPI as the isocyanate. In general, foam properties were comparable with those obtained from the prepolymer systems.

Urethane foams from animal fats: V. Flame resistant foams from hypohalogenated glycerides

A series of urethane foams has been prepared using hypohalogenated derivatives of triolein, monoolein, lard and tallow as the polyol ingredient. Two-step hypohalogenation was achieved by epoxidation of the glyceride, followed by treatment with HX. One step hypohalogenation was effected by direct addition of hypochlorous acid (from calcium hypochlorite) or hypobromous acid (from N-bromoacetamide). The polyols, which varied from viscous liquids to semi-solids, were adjusted in equivalent weight with triisopropanolamine. Urethane foams were prepared from the adjusted polyols using polymeric polyisocyanate as the isocyanate, triethylene diamine catalyst and Freon 11 as blowing agent. Additional foams were made with 2% antimony oxide as an added fire retardant. Rigid foams were obtained from each glyceride polyol. Fire retardant properties were measured using a modification of ASTM Method D1692-59T. In each case, the foams exhibited greater flammability resistance than those obtained from polyols containing no halogen atoms. It was noted that the presence of antimony oxide was necessary in order to attain nonburning foams but was accompanied by a lowering of compressive strength.

URETHANE FOAMS FROM ANIMAL FATS. I. OXYETHYLATED 9, 10-DIHYDROXYSTEARIC ACID.

Threo- anderythro-9,10-dihydroxystearic acids were reacted with 2, 4, 6 and 8 moles of ethylene oxide. The oxyethylated polyols from thethreo acid, adjusted to equivalent weight 100 with triisopropanolamine, were converted to satisfactory rigid foams by mixing with corresponding amts of isocyanate-terminated oxypropylated sorbitol prepolymers of three viscosities. Typical foam properties had maxima for the tetra- or hexaoxyethylene polyol, and most properties paralleled prepolymer viscosity.

Urethane foams from animal fats: VIII. Properties of foams from epoxidized tallow trimethylolpropane polyols

Polyols made by reacting trimethylolpropane with epoxidized tallow were converted to urethane foams by reaction with a polymethylene polyphenylisocyanate in the presence of fluorotrichloromethane. Adjusted with triisopropanolamine or an oxypropylated triamine to hydroxyl equivalent of either 100 or 120, the polyols yielded rigid foams of density 1.5–2.0 lb/ft3, open cell content 15–19%, and compressive strength 34–49 psi. These values were superior to those of similar foams from hydrated epoxidized tallow. Polyols made from epoxidized tallow-trimethylolpropane-HBr and adjusted to equivalent wt of 100 and 120 by triisopropanolamine gave foams whose small-scale flammability test samples burned less than 20% of their length. At hydroxyl equivalent 100, foams had density 1.6–1.8, open cell content 20–21%, and compressive strength 34–39 psi; in flammability tests burned <20% of length. The present foams were stronger than those made earlier from solvent-purified hydroxybrominated tallow. Formulation with half the normal amount of freon gave foams of higher compressive strength but lower flame resistance.

Urethane foams from animal fats. VI. Improved properties of lard and tallow-based foams

Improved properties of fire retardant urethane foams prepared from hypobrominated lard and tallow have been obtained by purification of the polyols prior to their use. Hypobromination was carried out by epoxidation of the glycerides followed by treatment with gaseous HBr. The crude derivatives were extracted with acetone and separated from unreacted saturates at 5 C. One step hypochlorination of glycerides by use of acidified sodium hypochlorite has been carried out, and subsequent purification of the polyols led to minor foam property improvement. Fire retardant foams have also been prepared from soybean oil and monoolein using both of these general methods, although the acetone extraction step could be omitted.

Urethane foams from animal fats: VII. Reaction of epoxidized tallow with trimethylolpropane and TMP-HBr

Polyols of higher hydroxyl content than previously obtained from tallow were prepared for use in urethane foams. Epoxidized tallow was caused to react with trimethylolpropane with catalysis by p-toluenesulfonic acid (2%). Reaction at 120 C in toluene gave best results. Alcoholysis occurred both at oxirane and at glyceride linkages, the latter reaction conferring hydroxyl functionality even on nonepoxidized glyceride units. Hydroxyl content of polyol products increased with the functional ratio of the reaction mixture, that is, the molar ratio of OH available from trimethylolpropane to oxirane plus ester from tallow. To provide fire retardant polyols, epoxidized tallow was caused to react with trimethylolpropane and gaseous HBr, best at 80 C in benzene. Examined by thin layer chromatography, the polyols showed polarities in the range of mono-and diglycerides.

Urethane foams from animal fats: IX. Polyols based upon tallow and trimethylolpropane; preparation under acidic and basic catalysis

A series of polyols was prepared from epoxidized tallow, by reaction with trimethylolpropane in refluxing toluene, sequentially under basic and acidic catalysis. In preliminary experiments, under catalysis by sodium methoxide alone, the trimethylolpropane reacted rapidly with glyceride linkages and very slowly with oxirane groups. Under catalysis by p-toluenesulfonic acid alone, oxirane was rapidly consumed. Polyols were prepared by the following sequences: (A) reaction under acidic followed by basic catalysis; (B) reaction under basic followed by acidic catalysis; (C) reaction under basic catalysis followed by further treatment with HBr gas to introduce fire retardance; (D) treatment of whole tallow first with trimethylolpropane under basic conditions and secondly with bromine; (E) reaction of epoxidized tallow with diethanolamine under basic catalysis; and (F) treatment of epoxidized tallow first with trimethylolpropane under acidic conditions and then with diethanolamine under basic catalysis. The polyols described were adjusted to equivalent weights of 100 and 120 with added triisopropanolamine and treated with a polymeric isocyanate to give rigid foams. Densities ranged from 1.5–1.8 lb/ft3. Open cell content, for foams made at the equivalent wt of 100, ranged from 14–21%; at the equivalent wt of 120, from 17–27%. Compressive strengths ranged from 14–23 psi, being lower than those of the best previous epoxidized tallow-trimethylolpropane products.

Urethane foams from animal fats. II. Reaction of propylene oxide with fatty acids

AbstractPropylene oxide has been reacted with 9,10-dihydroxystearic acid to form polyol components for urethane foams. The alkali-catalyzed reaction proceeds slowly until the first mole of propylene oxide is absorbed and thereafter at a higher rate. For other substrates, the initial reaction proceeds most readily with alcohols and decreases in speed with increasing acidity of the hydroxyl group. Threo-anderythro-9,10-dihydroxystearic acids were reacted with approximately 1, 2, 4, 6 and 8 moles of propylene oxide. Both series of the resulting polyols were liquid, unlike corresponding oxyethylated derivatives, which were solids in theerythro series. A small amount of unsaturation was observed in the reaction products in accord with previous studies. The liquid polyols can be used conveniently in the preparation of rigid urethane foams.

Urethane foams from animal fats. III. Oxypropylated dihydroxystearic acids in rigid foams

Liquid polyols consisting ofthreo-orerythro-9,10-dihydroxystearic acid previously reacted with 1, 2, 4, 6 and 8 moles of propylene oxide were adjusted with triisopropanolamine to equivalent weight 100. Using trichlorofluoromethane as blowing agent and triethylenediamine as catalyst, the adjusted polyols were foamed by reaction with a prepolymer made from oxypropylated sorbitol and tolylene diisocyanate.The resulting rigid foams had densities between 1.6 and 2.0 lb/ft3, the densities for thethreo series being parallel to but higher at each stage of oxypropylation than those of theerythro series. Compressive strengths in theerythro series ranged from 19 psi for the monooxypropylated compound to 38 psi for the octaoxypropylated member; in thethreo series from 27 to 39 psi. Properties improved in both series as the degree of polyol oxypropylation increased. This contrasted with foams prepared earlier from oxyethylated polyols, whose properties generally reached maxima at intermediate degrees of oxyethylation. Using the tetra-and hexaoxypropylatedthreo polyols, the proportion of blowing agent was varied to relate compressive strength to density of foams between 1.4 and 4 lb/ft3.

Urethane Foams From Animal Fats. XI. Urethane Polyols from Epoxidized Tallow, Sorbitol or Trimethylolpropane and Propylene Oxide; Preparation and Properties of Rigid Foams

Earlier studies at this laboratory established that polyols prepared from tallow-based intermediates could be conveniently used in the formulation of low density polyurethane rigid foams [1,2,3]. In the present work, highly functional polyol mixtures were prepared from the reaction of epoxidized tallow (ET) with sorbitol and propylene oxide (PO). The amounts of reactants, sorbitol and ET, were chosen in terms of their functional equivalent ratios (the ratio of hydroxyl equivalents available from sorbitol to oxirane plus ester equivalents from ET). To introduce fire retardancy, a parallel series of brominated polyols was also prepared. These and other polyols described below were used in formulating free-rise, low, medium, and high density rigid urethane foams. The low density foams reported here were formulated and evaluated essentially by procedures described in earlier publications [4,5]. In addition, medium and high density restricted rise foams were prepared in molds. The foams prepared from the tallow-derived polyols