possessing particular properties such as thermal stability, flexibility, and chemical resistance.Biomass polymers, [4][5][6] which are highly dependent on mechanical properties because they must sustain and recover from various deformations, have important potential applications in tissue engineering and drug delivery. [7][8][9] A novel elastomeric material, poly(glycerol sebacate) (PGS), has excellent mechanical stability derived from a soft, tough, and elastomeric network structure. [8] These elastomers, which form a cross-linked and 3D network of random coils, are similar to vulcanized rubber. Such paths to obtain strong and elastomeric characterizations are also observed in nature, such as in collagen and elastin. The covalent crosslinking and hydrogen bonding interactions contribute additional mechanical strength, which makes PGS much tougher than most hydrogels and able to withstand larger reversible deformations than can PHA and P4HB. [10] This study proposed two potential strategies to achieve PGS-like materials: 1) excellent mechanical properties could be reached through interactions of intramolecular cross-linked covalent bonds and intermolecular hydrogen bonds; and 2) a rubber-like elastomer could be obtained using one monomer of the trifunctional group as a node to form a 3D network structure.The toxicological and safety aspects of glycerol and sebacic acid (SeA) have been approved and passed by the US Food and Drug Administration for biomedical applications [11] in myocardial tissue, vascular graft, and cartilage. [12][13][14] SeA, as a specific monomer, is a nontoxic material, and it was employed in this study. Commonly, SeA is made of castor oil and manufactured by saponification at 250 °C. The long-chain aliphatic dicarboxylic acid (HOOC(CH 2 ) n COOH) with a chain length of n = 8 is more suitable to cyclize during polymerization reactions compared with short-chain dicarboxylic acids, such as AA. In general, the methods of producing green monomers involve fermentation and chemical transformations from natural polymers and molecular biomass from nature. [15] Among all green monomers, vegetable oils with their fatty acids are particularly appealing because of their relatively low toxicity, availability at
Smart TextilesIn this study, materials with low melting temperatures and high toughness are developed for orthopedic applications. A series of an aliphatic copolyester based on sebacic acid (SeA), a green resource, is copolymerized with ethylene glycol, trimesic acid, aminocaproic acid, and adipic acid (AA) to produce poly(ethylene sebacate-co-ethylene adipate) (PESA) with various molar ratios through melt polymerization. Thermal characterizations of the PESA copolyesters are tuned with SeA and AA in varying molar ratios, exhibiting a crystalline phase with a lower degree of perfection. The melting point (T m ) and crystallization temperature (T c ) of the copolyesters are observed at 60-70 and 30-40 °C, respectively. Furthermore, a high Young's modulus ranging between 140 and 200 MPa is observed...
