Amine-cured ω-epoxy fatty acid triglycerides: Fundamental structure–property relationships

Investigation of the Impact of Two Types of Epoxidized Vietnam Rubber Seed Oils on the Properties of Polylactic Acid

To minimize the brittleness of polylactic acid (PLA), the epoxidized rubber seed oils (ERO) or epoxidized ester rubber seed oils (EERO) are blended with PLA. The mechanical properties of ERO bioblend are higher than that of EERO bioblend and significantly improved compared to that of the PLA sample. Elongation at break is increased by 9.1 times, and impact strength and tensile toughness improved by 139% and 1370%, respectively. The morphological study showed the microdroplets of epoxidized oils distributed in the ERO bioblend are much smaller than those in the EERO bioblend. This means that the ERO is better compatible with PLA, and both ERO and EERO are partially miscible with PLA. This compatibility is confirmed by the decrease in the glass transition temperature, $T_{\text{g}}$ , from 65.7 to 60.5°C. The TGA analysis shows a sharp increase in an initial decomposition temperature (from 261.8 to 311.9°C) meaning an improvement in thermal properties. The NMR analysis proves that the epoxidized vegetable oils are linked to PLA chains, so both the melt flow index and an acid value of ERO or EERO bioblend decrease while the thermal stability is improved. The NMR peak area of some signals shows that the ERO is more attached to PLA, proving better compatibility of ERO with PLA, resulting in higher mechanical properties of ERO bioblend. The plasticizing effect of plasticizers is not dependent on the oxygen-oxirane content of the epoxidized oil but is strongly influenced by the acid value. Overall results show that both ERO and EERO can be used as a biodegradable, renewable plasticizer to replace petroleum-based plasticizers for PLA. In addition, the successful modification of PLA by using ERO or EERO promotes the use of this polymer as a potential material for researchers working on PLA applications.

Vegetable-oil-based polymers as future polymeric biomaterials

Vegetable oils are one of the most important classes of bio-resources for producing polymeric materials. The main components of vegetable oils are triglycerides - esters of glycerol with three fatty acids. Several highly reactive sites including double bonds, allylic positions and the ester groups are present in triglycerides from which a great variety of polymers with different structures and functionalities can be prepared. Vegetable-oil-based polyurethane, polyester, polyether and polyolefin are the four most important classes of polymers, many of which have excellent biocompatibilities and unique properties including shape memory. In view of these characteristics, vegetable-oil-based polymers play an important role in biomaterials and have attracted increasing attention from the polymer community. Here we comprehensively review recent developments in the preparation of vegetable-oil-based polyurethane, polyester, polyether and polyolefin, all of which have potential applications as biomaterials.

Controlled RAFT synthesis of side-chain oleic acid containing polymers and their post-polymerization functionalization

We report the synthesis and characterization of well-defined polymers from oleic acid as the bio-renewable resource. Double bonds in oleate side-chains in the polymer are further modified by thiol-ene reaction, epoxidation, and cross-linking.

Analysing the Temperature Effect on the Competitiveness of the Amine Addition versus the Amidation Reaction in the Epoxidized Oil/Amine System by MCR-ALS of FTIR Data

The evaluation of the temperature effect on the competitiveness between the amine addition and the amidation reaction in a model cure acid-catalysed reaction between the epoxidized methyl oleate (EMO), obtained from high oleic sunflower oil, and aniline is reported. The study was carried out analysing the kinetic profiles of the chemical species involved in the system, which were obtained applying multivariate curve resolution-alternating least squares (MCR-ALS) to the Fourier transform infrared spectra data obtained from the reaction monitoring at two different temperatures (60°C and 30°C). At both experimental temperatures, two mechanisms were postulated: non-autocatalytic and autocatalytic. The different behaviour was discussed considering not only the influence of the temperature on the amidation reaction kinetic, but also the presence of the homopolymerization of the EMO reagent.

Undecylenic acid: a valuable and physiologically active renewable building block from castor oil

A lot of attention is currently being paid to the transition to a biobased economy. In this movement, most efforts concentrate on the development of bioenergy applications including bioethanol, biodiesel, thermochemical conversion of biomass, and others. However, in the energy sector other nonbiomass alternatives are known, whereas no valuable alternatives are available when thinking about chemical building blocks. Therefore, it is also essential to develop new routes for the synthesis of bio-based chemicals and materials derived thereof. Such intermediates can originate either from plants or from animals. Castor oil is a non-edible oil extracted from the seeds of the castor bean plant Ricinus communis (Euphorbiaceae), which grows in tropical and subtropical areas. Globally, around one million tons of castor seeds are produced every year, the leading producing areas being India, PR China, and Brazil.2 10-Undecenoic acid or undecylenic acid is a fatty acid derived from castor oil that, owing to its bifunctional nature, has many possibilities to develop sustainable applications.