A Novel Multiblock Copolymer of CO₂-Based PPC-mb-PBS: From Simulation to Experiment

Abstract

A kind of new biodegradable materials with high performance in a wide range of temperatures was effectively developed via the combination of theoretical calculations and experimental works. The new polymer of poly­(propylene carbonate)-multiblock-poly­(butylene succinate) (PPC-mb-PBS) was designed and synthesized from poly­(propylene carbonate) (PPC) and poly­(butylene succinate) (PBS) segments. The simulation was successfully performed based on their multiblock topology structure. On the basis of the calculation, the T g of PPC-mb-PBS calculated by molecular dynamics (MD) simulation ranges from −42 to −38 °C that is independent of the block size of PPC segments. The end-to-end distance and mean square displacement (MSD) calculations indicate an inversion behavior of the PPC and PBS between hard and soft segments at different temperatures. The stress–strain behavior of PPC-mb-PBS was also calculated by the MD simulation of uniaxial deformation. The simulated stress of PPC-mb-PBS copolyesters is higher than that of pure PPC under uniaxial extension with the same strain and is found to increase with decreasing PPC block size. To verify the validity of the simulation, the PPC-mb-PBS multiblock copolyesters with various designed block length were synthesized and characterized by 1H NMR, DOSY, and GPC. Meantime, their thermal and mechanical properties were determined, respectively, by DSC and tensile testing. The measured T g data and the variation tendency of tensile strength are in very good agreement with the simulated results, demonstrating the ability of the fully atomic-scale MD simulations to well predict the mechanical properties of the synthesized biodegradable polymers.

Recent advances on the structure–properties relationship of multiblock copolymers

“…Also, it requires to compute interactions for the different couples of beads, that is, AA, AB and BB resulting in a minimum of five different potentials to be defined. Once fixed the model parameters and the chains topology (linear, 132,133 star, 81,134 ring, 135,136 …), the simulation box is equilibrated at high temperature. One can then focus on the phase separation occurring upon cooling, by following the variation of volume (or enthalpy).…”

Synthesis of statistical poly(ethylene terephthalate‐co‐2,6‐naphthalate) (co)polymers and study on their properties: Thermal and barrier properties

“…In the constructed water/oxygen‐PEN, water/oxygen‐PET and water/oxygen‐PETN blending models, the number of polymer molecular chains is 10, the number of water and oxygen molecules is 20, and the mass fraction of water and oxygen is 0.5% and 0.8%, respectively. In the process of dynamic simulation, COMPASS II force field was used for polymer, water and oxygen molecules 39,40 . After the water/oxygen‐PEN, water/oxygen‐PET and water/oxygen‐PETN blending models are established respectively, the intermolecular stress of the system is eliminated by annealing kinetics simulation and the energy of the system is optimized.…”

Poly(Propylene Carbonate)-Based Biodegradable and Environment-Friendly Materials for Biomedical Applications

“…For example, Meng et al used the -COOH of poly(butylene succinate) (PBS) to block the -OH of PPC. Both theoretical calculations and experimental data showed enhanced toughness and strength for the synthesized PPC-mb (multiblock)-PBS [ 106 ]. In addition, other capping agents, such as maleic anhydride, benzoyl chloride and isocyanate, have also been utilized to protect the terminal -OH of PPC [ 107 ].…”