Biodegradable Multiblock Copolyesters Prepared from ε-Caprolactone, l-Lactide, and Trimethylene Carbonate by Means of Bismuth Hexanoate

Abstract

Telechelic random copolymers were prepared by copolymerization of ε-caprolactone (εCL) and trimethylene carbonate (TMC) in bulk using bismuth(III) hexanoate, Bi(OHex)3, as initiator. These copolymers were characterized by 1H and 13C NMR spectroscopy. A−B−A triblock copolymers were synthesized by chain extension of these random copolymers with l-lactide, whereby the chain length of the amorphous central blocks and of the crystalline poly(l-lactide) blocks were varied. Finally, the triblock copolymers were transformed into multiblock copolymers by chain extension with 1,6-hexamethylenediisocyanate. All three synthetic steps were performed in a “one-pot-procedure”. The resulting multiblock copolymers were characterized by 1H NMR spectroscopy, SEC measurements, DSC measurements, and stress−strain measurements. Typical mechanical properties of thermoplastic elastomers were detected.

Aliphatic-aromatic poly(ester-carbonate)s obtained from simple carbonate esters, α,ω-aliphatic diols and dimethyl terephthalate

“…Structure of the obtained poly(alkylene terephthalate-cocarbonate)s was also confirmed by 13 C NMR spectra analysis (exemplary spectra is shown for TC4-46 in Fig. 4).…”

“…Usually polymers obtained by polycondensation exhibit poor mechanical properties due to relatively small molar mass. To obtain high molar mass poly(ester-carbonate)s copolymerization of cyclic esters (L-lactide, ε-caprolactone) with cyclic carbonate monomer-trimethylene carbonate (TMC) is usually carried out [12][13][14]. Besides TMC for copolymerization with cyclic esters other six-membered cyclic carbonates with different functional groups are also used [15][16][17][18].…”

Synthesis of Poly[(ethylene carbonate)‐co‐(ethylene oxide)] Copolymer by Phosphazene‐Catalyzed ROP

“…[1][2][3][4][5] Generally, they can be synthesized via ring-opening polymerization (ROP) of the corresponding cyclic carbonates with cationic, anionic, coordinated, or enzymatic catalysts. [6][7][8][9] 1,3-Dioxolan-2-one (DOO) or ethylene carbonate (EC) with a fi ve-membered ring is the most commonly used cyclic carbonate, and it can be polymerized into poly[(ethylene monomer to catalyst was 1000:1 and the polymerization was carried out at 180 ° C. The band at 1700 cm − 1 is attributed to carbonyl, whereas the bands at 1250-1300 cm − 1 and 1000-1150 cm − 1 are assigned to the C-O bond of the carbonate in EC and the C-O bond of the ether in EO, respectively.…”

Enhancing mechanical properties of thermoplastic polyurethane elastomers with 1,3-trimethylene carbonate, epsilon-caprolactone and L-lactide copolymers via soft segment crystallization

“…To replace the role of the diisocyanate hard segments, PCL-co-PTMC soft segment was further reacted with L-LA to form A-B-A structure, yielding 'pseudo hard segments' via PLLA crystallization. Kricheldorf and Rost [15] have recently studied a similar system, PLLA-b-(PCL-co-PTMC)-b-PLLA multiblock copolymers synthesized by using bismuth(III) hexanoate as catalyst. However, they focused on the polymerization mechanism studies without emphasizing the relationship between mechanical property and PLLA crystallization.…”