Microstructure and Mechanical/Elastic Performance of Biobased Poly (Butylene Furanoate)–Block–Poly (Ethylene Oxide) Copolymers: Effect of the Flexible Segment Length

Abstract

The aim of this paper is to extend knowledge on biobased poly(butylene furanoate)–block–poly (ethylene oxide) (PBF-b-PEO) copolymers’ performance by studying the effect of the PEO segment’s molecular weight on the microstructure and materials behavior. As crystallization ability of PEO depends on its molecular weight, the idea was to use two PEO segment lengths, expecting that the longer one would be able to crystallize affecting the phase separation in copolymers, thus affecting their mechanical performance, including elasticity. Two series of PBF-block-PEOs with the PEO segments of 1000 and 2000 g/mol and different PBF/PEO segment ratios were synthesized by polycondensation in melt, injection molded to confirm their processability, and subjected to characterization by NMR, FTIR, DSC, DMTA, WAXS, TGA, and mechanical parameters. Indeed, the PEO2000 segment not only supported the crystallization of the PBF segments in copolymers, but at contents at least 50 wt % is getting crystallizable in the low temperature range, which results in the microstructure development and affects the mechanical properties. While the improvement in the phase separation slightly reduces the copolymers’ ability to deformation, it is beneficial for the elastic recovery of the materials. The investigations were performed on the injection molded samples reflecting the macroscopic properties of the bulk materials.

The effect of annealing on tensile properties of injection molded biopolyesters based on 2,5‐furandicarboxylic acid

“…[48] Moreover, in our earlier works, it was observed, that the longer the diol chain, the faster the polyester crystallizes. [16,49,50] Similar observations have been reported by Chuah, [51] for polyesters based on TPA. Before annealing, both PEF and PTF were amorphous, therefore, only glass transitions can be observed for these polyesters (Figure 2).…”

Tuning the Properties of Furandicarboxylic Acid-Based Polyesters with Copolymerization: A Review

“…Lanthanum(III) acetylacetonate [ 73 , 79 ], polyphosphoric acid [ 72 ], cobalt acetate [ 41 ], dibutyltin oxide [ 33 , 68 ], and EG antimony [ 48 ] have also occasionally been used. Additives, mainly Irganox 1010, a sterically hindered phenolic primary radical scavenger common in the synthesis of many types of polymers, are periodically used as antioxidants and heat stabilizers [ 48 , 56 , 58 , 85 , 91 ].…”

“…When it comes to the structure of the products, random copolymers are mostly obtained. Block or multiblock copolymers are obtained in copolymers incorporating polyether segments, such as poly(ethylene glycol) (PEG) or poly(tetramethylene glycol) (PTMG) [ 46 , 47 , 48 , 56 , 88 , 89 , 90 , 91 , 93 , 94 , 101 ]. When ROP with CL or lactide is included in the polymerization, the outcome depends on the experimental conditions, and both random [ 49 , 54 , 85 ] and block copolymers [ 54 , 87 , 95 , 98 ] have been obtained.…”

“…EG and BDO are commonly used biodegradable comonomers for the production of ductile FDCA-containing copolymers [ 47 , 48 , 56 , 89 , 90 , 91 , 94 ]. When amorphous PEG of low Mw is used (1000–6000 g/mol), a decrease in tensile strength and Young’s modulus is observed along with the significant increase in elongation [ 47 , 56 , 89 , 91 , 94 ]. Bigger PEG segments (e.g., 10,000 and 20,000 g/mol) on the other hand reduce the ε b and increase the E because of their high crystallinity [ 90 ].…”

“…Some are discussed as the biobased alternatives of PBAd- co -PBT, which also possess better barrier and mechanical properties, such as PBF- co -PGA [ 92 ]. Polyactive™ is a biodegradable PET- co -PEO copolymer used for drug delivery and tissue engineering that could potentially be replaced by PBF- co -PEG copolymers [ 90 , 91 ]. PBAd- co -PBT, known as Ecoflex ® , can be replaced by PBF- co -PBAd or PBF- co -PBS copolymers [ 72 , 74 , 75 ].…”