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Novel thermosetting copolymers, ranging from tough and ductile to very soft rubbers, have been prepared by the cationic copolymerization of regular (SOY) and 100% conjugated soybean oils (C(100)SOY) with dicyclopentadiene (DCP) catalyzed by Norway fish oil (NFO)-modified and SOY- and C(100)SOY-diluted boron trifluoride diethyl etherate (BFE). The gelation time of the reactions varies from 4 to 991 min at 110 degrees C. The yields of the bulk copolymers are essentially quantitative, while the yields of the cross-linked copolymers remaining after Soxhlet extraction with methylene chloride range from 69% to 88%, depending on the monomer stoichiometry and the catalyst used. (1)H NMR spectroscopy and Soxhlet extraction data indicate that these copolymers consist of a cross-linked soybean oil-DCP network plasticized by certain amounts of methylene chloride-soluble linear or less cross-linked soybean oil-DCP copolymers, unreacted oil, and some low molecular weight hydrolyzed oil. The molecular weights of these soluble fractions are in the range from 400 to 10,000 g/mol based on polystyrene standards. The bulk copolymers have glass transition temperatures ranging from -22.6 to 56.6 degrees C, while their tan delta peak values range from 0.7 to 1.2. Thermogravimetric analysis (TGA) indicates that these soybean oil-DCP copolymers are thermally stable below 200 degrees C, with 10% and 50% weight loss temperatures ranging from 280 to 372 degrees C and 470-554 degrees C, respectively. These properties suggest that these biobased thermosets may prove useful alternatives to current petroleum-based plastics and find widespread utility.

The structural isomers formed by the homogeneous rhodium-catalyzed isomerization of several vegetable oils have been elucidated. A detailed study of the isomerization of the model compound methyl linoleate has been performed to correlate the distribution of conjugated isomers, the reaction kinetics, and the mechanism of the reaction. It has been shown that [RhCl(C8H8)2]2 is a highly efficient and selective isomerization catalyst for the production of highly conjugated vegetable oils with a high conjugated linoleic acid (CLA) content, which is highly desirable in the food industry. The combined fraction of the two major CLA isomers [(9Z,11E)-CLA and (10E,12Z)-CLA] in the overall CLA mixture is in the range from 76.2% to 93.4%. The high efficiency and selectivity of this isomerization method along with the straightforward purification process render this approach highly promising for the preparation of conjugated oils and CLA. Proposed improvements in catalyst recovery and reusability will only make this method more appealing to the food, paint, coating, and polymer industries in the future.

The free-radical copolymerization of 40-85 wt % of conjugated low-saturation soybean oil (CLS), and a 9 : 1 ratio of acrylonitrile (AN) and either divinylbenzene (DVB) or dicyclopentadiene (DCP) using AIBN as the initiator affords transparent yellow samples, which range from hard to slightly rubbery. DMA analysis indicates that the samples containing DCP have tan d values ranging from 0.32 to 0.49, while the damping properties of the DVB samples are slightly lower. Extraction analysis shows that complete chemical incorporation of the CLS into the polymeric network is achieved when the original CLS content ranges from 40 to 65 wt %. Lower incorporation of the CLS into the polymer network occurs when the oil content exceeds 70 wt %. In this case, up to 30% of the CLS remains unreacted. These observations are supported by 1 H NMR and solid-state NMR. Thermogravimetric analysis indicates a just one important stage of degradation, implying that the polymer network is highly homogeneous in composition. The temperatures of 10% weight loss for the DCP system range from 402 to 4288C, and from 370 to 3918C for the DVB system. The temperature of maximum degradation ranges from 458 to 5188C for the DCP polymers, and 406 to 4228C for the DVB system.

New polymeric thermosets were prepared through the bulk free-radical copolymerization of 100% conjugated linseed oil, acrylonitrile, and divinylbenzene. Under the appropriate reaction conditions and with the appropriate curing sequence, 61-96 wt % of the oil was incorporated into the crosslinked thermosets. The resulting yellow, transparent thermosets varied from being soft and flexible to being hard and brittle. Dynamic mechanical analysis and thermogravimetric analysis showed that these thermosets had good mechanical properties and thermal stability.

A series of various soybean oil/dicyclopentadiene (DCP) thermosetting copolymers with renewable carbon percentages of 53–86% have been prepared by cationic copolymerization of regular (SOY) or 100% conjugated soybean oils (C100SOY) with DCP initiated by NFO ethyl ester modified and SOY‐ and C100SOY‐diluted BF3 diethyl etherate. The effects of stoichiometry, the type of soybean oil, and the initiator on the mechanical and damping properties of the copolymers have been investigated. The materials exhibit compressive stress/strain behavior ranging from soft rubbers to tough and ductile plastics, and possess good damping properties. They represent promising new materials for efficient sound and vibration damping applications over a broad temperature and frequency range.magnified image

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