Catalyst-Free Single-Step Solution Polycondensation of Polyesters: Toward High Molar Masses and Control over the Molar Mass Range

Abstract

Poly(alkylene terephthalate)s are frequently used polymers serving a plethora of applications, including packaging, textiles, and biomedical applications. However, their current synthesis procedures have some limitations, such as harsh reaction conditions and requirement of a catalyst. Furthermore, there is no control over the molar mass and only polymers with limited molar masses can be obtained. New optimized synthesis methods are therefore desired. To this end, we further improved our previously reported catalyst-free single-step solution polycondensation. By varying the comonomer ratio of both monomers, we gained control over the molar mass range and obtained polymers with number-average molar masses up to 187 kg/mol. Furthermore, by using a small excess of diol, we obtained polymers with alcohol end groups, allowing further functionalization. Finally, the melt recrystallization behavior for all investigated polymers was demonstrated using modulated differential scanning calorimetry. In conclusion, the synthesis method described in this paper circumvents the disadvantages of the current synthesis procedures.

Recyclable, Reprocessable, Anticorrosive, and Hydrolysis-Resistant Long-Chain Aliphatic Polycarbonates as Polyethylene-like Materials

“…For example, diffraction peaks of PC-12 and PC-14 marginally shifted to lower 2θ angles, while those of PC-13 and PC-15 slightly migrated toward opposite direction. Although this plausible odd−even effect has been observed in various long-chain aliphatic polycondensates especially for their thermal parameters, 19,34,56 this trend is rarely reported in WAXD patterns. 57 3.3.…”

Effect of molar mass and alkyl chain length on the surface properties and biocompatibility of poly(alkylene terephthalate)s for potential cardiovascular applications

“…46–48 The reason for the deviation of the lowest molar mass from this trend is unclear. We hypothesize that this might be because of the faster crystallization behavior of lower molar mass polymers 40 during spin-coating, which could result in inferior film-forming properties and, in turn, lead to a higher surface roughness.…”

“…[37][38][39] We previously developed a novel one-step synthesis method by which PATs can be synthesized via a relatively simple set-up, using milder reaction conditions than the conventional melt polycondensation approach and without using a catalyst or other additives. 39,40 By avoiding the harsh reaction conditions, the formation of potentially harmful side products (e.g. acetaldehyde and diethylene glycol during the synthesis of PET) is prevented.…”

“…acetaldehyde and diethylene glycol during the synthesis of PET) is prevented. 37,[40][41][42] Furthermore, by circumventing the need for a catalyst, which is often toxic, this synthesis method is much more appealing than the conventional melt polycondensation for the synthesis of PATs serving biomedical applications. 37,39,43,44 In this work, thin polymeric spin-coated films of PATs with an alkyl chain length n Z 8 were prepared and their surface was characterized using atomic force microscopy (AFM) and water static contact angle (WSCA) measurements.…”

“…acetaldehyde and diethylene glycol during the synthesis of PET) is prevented. 37,40–42 Furthermore, by circumventing the need for a catalyst, which is often toxic, this synthesis method is much more appealing than the conventional melt polycondensation for the synthesis of PATs serving biomedical applications. 37,39,43,44…”