Castor Oil-Based Biodegradable Polyesters

Abstract

This Review compiles the synthesis, physical properties, and biomedical applications for the polyesters based on castor oil and ricinoleic acid. Castor oil has been known for its medicinal value since ancient times. It contains ∼90% ricinoleic acid, which enables direct chemical transformation into polyesters without interference of other fatty acids. The presence of ricinoleic acid (hydroxyl containing fatty acid) enables synthesis of various polyester/anhydrides. In addition, castor oil contains a cis-double bond that can be hydrogenated, oxidized, halogenated, and polymerized. Castor oil is obtained pure in large quantities from natural sources; it is safe and biocompatible.

Rational design of sustainable polyurethanes from castor oil: towards simultaneous reinforcement and toughening

“…It is noted that the sustainable polymers synthesized directly from vegetable oils usually show poor mechanical performance leading to limited application [10][11][12]. Although high performance polymers such as polyamides, polyesters and epoxy thermosets can be prepared from monomers derived from vegetable oils through well-designed chemistry techniques, the conversion of vegetable oils to monomers increases the cost of the resultant materials inevitably [3,7,13]. If high performance sustainable polymers can be prepared from vegetable oils directly without undergoing monomer conversion step, they would be much more commercially competitive due to the increased cost-efficiency.…”

Biodegradable polymers from monomers based on vegetable oils

“…Compared to other vegetable oils, castor oil is a special monomer for polymerization, because it contains about 90 % bifunctional ricinoleic acid with a double bond between the 9 th and 10 th position and an inherent hydroxyl group in the 12 th position. The ricinoleic acid can be produced by hydrolysis of castor oil [78]. The structures of castor oil and ricinoleic acid are shown in Scheme 17.…”

“…The unique trifunctional castor oil can be considered as triol, which can copolymerize directly with dibasic acid, such as sebacic acid, to form hyperbranched or cross-linked polyesters. Castor oil based copolymerized, hyperbranched or cross-linked polymers have been widely used in biomedical applications, such as drug carrier and tissue engineering scaffold, due to their flexibility, hydrophobicity and injectability [78].…”

Biodegradable Polymers: Medical Applications

“…They degrade into natural body components, and the hydrophobic nature of fatty acid causes bulk degradation. Polyanhydrides and polyesters based on ricinoleic acid form in situ gel depots when in contact with water (43). Gliadel R is a PCPP-SA polyanhydride for the controlled delivery of chemotherapeutic drugs to brain in the treatment of cancer.…”