Copolymers from Unsaturated Macrolactones: Toward the Design of Cross-Linked Biodegradable Polyesters

Abstract

The enzymatic synthesis of a series of random copolyesters by ring-opening polymerization of unsaturated macrolactones like globalide and ambrettolide with 1,5-dioxepan-2-one (DXO) and 4-methyl caprolactone (4MeCL) was investigated. (13)C NMR diad analysis confirmed the randomness of all copolymers irrespective of the comonomer ratios. Thermal investigation showed that incorporating the comonomers lowered the melting points of the polymers as compared with the macrolactone homopolymers. The decrease was dependent on the comonomer ratio. The unsaturated copolymers were thermally cross-linked using dicumyl peroxide, which resulted in completely amorphous insoluble networks. It was found that 10% incorporation of the unsaturated macolactone was sufficient to obtain a gel content of 95 wt %. Preliminary degradation tests confirm that the cross-linked copolymers are enzymatically degradable and that the incorporation of hydrophilic comonomers like DXO enhances degradation.

Block Copolymers of “PE-Like” Poly(pentadecalactone) and Poly(l-lactide): Synthesis, Properties, and Compatibilization of Polyethylene/Poly(l-lactide) Blends

“…During all sequential feed ROP reactions, both monomers were polymerized to high conversions (>95%) and number-average molecular weights varying between 60 and 81 kg·mol −1 were obtained. The reaction mixtures were quenched, washed using methanol and dried, after which DSC, 13 C NMR and MALDIToF-MS analyses gave similar results as obtained for the previously prepared poly(PDL-block-LLA) copolymers (PPL1−PPL6). Therefore, P26L74, P52L48, and P77L23 are also assumed to consist of linear poly(PDL-block-LLA) as the major component and cyclic PPDL and PLLA homopolymer as the minor component.…”

“…The lack of signals originating from end-groups or linkages between PDL and LLA is caused by their relative low concentration. However, analysis and peak assignment of the co-oligomer (OPL3, Figure 4b) using a combination of 13 The presence of the PDL-LLA diads in 13 C NMR, in combination with the increase in molecular weight obtained from SEC and the two individual melting peaks for both blocks observed in DSC is convincing evidence for the formation of poly(PDL-block-LLA) copolymers.…”

Photoinduced thiol–ene crosslinking of globalide/ε‐caprolactone copolymers: Curing performance and resulting thermoset properties

“…The enzymatic polymerization of these monomers produces polymers with excellent mechanical properties,15 which has led to recent investigation of, for example, poly(pentadecalactone), in coating and fiber applications 4, 16. One such macrolactone, globalide, having 15 carbons and an unsaturation on the backbone, has been successfully polymerized by lipase catalysis to form a linear multifunctional alkene polymer 17, 18. The unsaturation in the globalide monomer allows these polymers to be crosslinked or further functionalized with any moiety that can react with an alkene 18, 19.…”

“…One such macrolactone, globalide, having 15 carbons and an unsaturation on the backbone, has been successfully polymerized by lipase catalysis to form a linear multifunctional alkene polymer 17, 18. The unsaturation in the globalide monomer allows these polymers to be crosslinked or further functionalized with any moiety that can react with an alkene 18, 19. The 1,2‐disubstituted alkene group in globalide has, however, poor radical homopolymerization abilities due to degradative chain transfer and overall slow propagation rate, which is why it is difficult to use them as thermosets alone 20.…”

Thermoplastic Poly(urethane urea)s From Novel, Bio‐based Amorphous Polyester Diols

“…The hydrolytic degradability in a 0.1 M PBS (buffer) solution (pH 7.4) of the TPUUs was studied by using the enzyme pseudomonas cepacia Lipase (Lipase PS), which is reported23 to be an efficient enzyme in the hydrolytic (bio)degradation of polyesters. The temperature at which the hydrolysis experiments were performed is 37 °C.…”