Synthesis of poly(butylene succinate‐co‐butylene terephthalate) (PBST) copolyesters with high molecular weights via direct esterification and polycondensation

Abstract

In this article, biodegradable poly(butylene succinate-co-butylene terephthalate) (PBST) copolyesters with high molecular weights were synthesized by direct esterification and polycondensation route. The reaction conditions and catalytic systems were investigated in detail. Through balancing the reaction efficiency and the costs of reactants, the proper molar ratio of diol to diacid was determined. Titanium tetraisopropoxide (TTiPO) was found to be an effective catalyst both in esterification and polycondensation reaction, and its content was optimized based on the esterification ratio and amount of formed by-products. The complex reaction was determined to be the dominant catalytic reaction mechanism. By importing the additives of metal oxides coupled with TTiPO, the weight-average molecular weights of PBST increased sharply from 8.51 Â 10 4 to 14.38 Â 10 4 , manifesting the additives promoted the polymerization reaction greatly. The enhancement of carbonyl polarization and provision of suitable reaction space arose from the metal oxides were the reasons for promoting the polymerization reaction. With respect to thermal properties, the same melting point and heat of fusion were found, while thermal stability increased with the import of additives. The result was prone to be interpreted by the higher molecular weights of PBST in the presence of additives.

Lamellae evolution of poly(butylene succinate-co-terephthalate) copolymer induced by uniaxial stretching and subsequent heating

“…41 The chemical structure of PBST and its monomers are shown in Scheme 1. 41 The chemical structure of PBST and its monomers are shown in Scheme 1.…”

“…[40][41][42] Recently, unstable morphologies fundamentally ascribed to complex structure transformation in dynamic environments have been encountered in the manufacturing of PBST bers, resulting in relatively poor mechanical properties and low productivity. We have reported its preparation, structure, properties and application in the form of elastic bers with high elastic recovery in previous work.…”

Synthesis of poly(butylene succinate) using metal catalysts

“…Succinic acid can be produced from carbohydrates through fermentation, using Anaerobiospirillum succiniciproducens [26][27][28][29][30][31]. During the fermentation process, CO 2 is consumed, contributing to carbon sequestration [32].…”

The kinetics of poly(butylene succinate) synthesis and the influence of molar mass on its thermal properties

“…More recently, the efficiency of organometal‐ and metal oxide‐based catalysts has been highlighted for the transesterification step of the synthesis of PBS . Luo et al proposed a catalytic reaction mechanism for the complex reaction of PBST with high molar masses. Moreover, several authors have reported the synthesis of PBS with high molar mass (up to M n = 70,000 g mol −1 ) through the direct polycondensation of SA and 1,4‐butanediol (BDO).…”