Tailoring Crystallization of Random Terpolyester: Combination of Isodimorphism and Isomorphism

Abstract

Isodimorphism and isomorphism are becoming mature approaches but separately used to regulate crystallization behavior of random copolymers and thus their performances. Most of the research work is focused on binary copolymers while leaves random copolymers containing more than two kinds of comonomeric units rarely studied in which both isodimorphism and isomorphism may occur together. This experiment is realized in the terpolymers of poly­(butylene adipate-ran-butylene succinate-ran-butylene fumarate) (PBASF) wherein butylene adipate (BA) displays isodimorphic behavior with either butylene succinate (BS) or butylene fumarate (BF), and BF builds an isomorphic structure with BS. When the BA content is kept almost unchanged at ∼50 mol %, PBASF can be subtly tailored from a pseudoeutectic state to only isomorphic state by increasing the BF content that suppresses the crystallizability of the PBA-rich phase but hardly affects the PBSF-rich phase. Crystallization behaviors of PBASF from both melt and quenched samples are assayed in detail by using a differential scanning calorimeter, X-ray diffractometer/scatterometer, and Fourier transformation infrared spectrometer, and the mechanism of confined crystallization is clearly unraveled, which is relied on both intersegment hydrogen-bonding interaction and physical restriction. Furthermore, a crystal phase diagram for random terpolymer of PBASF is proposed, which provides an overall guide to tailor its crystallization. This example of the strategy combining isodimorphism and isomorphism raised here sheds light on precise regulation of properties and performances of terpolymer and copolymer with more complicated chain structures.

Marine Biodegradation of Poly(butylene succinate) Incorporating Disulfide Bonds Triggered by a Switch Function in Response to Reductive Stimuli

“…The d spacing values are not constant but increase compared to the main components in PBSDT0 with increasing BDTG content. This result indicates expanding d spacing due to the formation of cocrystals of BS and BDTG units as well as the crystal structure of poly­(butylene succinate- co -butylene adipate) (PBSA). ,, Butylene adipate-rich PBSA showed main reflections similar to the poly­(butylene adipate) (PBA) homopolymer. PBSDT68 did not have the same reflection pattern as PBSDT100, suggesting that the BS unit hampers BDTG crystallization.…”

Synthesis, Structure, Crystallization and Mechanical Properties of Isodimorphic PBS-ran-PCL Copolyesters

“…Our group has recently studied isodimorphism in several random copolymer systems [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. Isodimorphic crystallization has recently been found in different types of random copolymers such as poly (decamethylene succinate- ran -decamethylene fumarate), poly (butylene succinate-co-cis-butene succinate) and poly (hexamethylene carbonate)-co-poly (hexamethylene urethane) [ 30 , 31 , 32 , 33 , 34 , 35 ].…”

“…Our group has recently studied isodimorphism in several random copolymer systems [19][20][21][22][23][24][25][26][27][28][29]. Isodimorphic crystallization has recently been found in different types of random copolymers such as poly (decamethylene succinate-ran-decamethylene fumarate), poly (butylene succinate-co-cis-butene succinate) and poly (hexamethylene carbonate)-co-poly (hexamethylene urethane) [30][31][32][33][34][35]. (3) Total exclusion behavior: When the repeating units of two homopolymers are dissimilar, the minor comonomer would be completely kept out from the crystalline structure of the main component.…”

A Review on Current Strategies for the Modulation of Thermomechanical, Barrier, and Biodegradation Properties of Poly (Butylene Succinate) (PBS) and Its Random Copolymers

“…Similar behavior was also found by Zheng et al [71] in multiblock copolymers of PBS-co-PBF. In the following contribution, Ye et al found that in random terpolyester PBS-ran-PBF-ran-PBA [72], the PBS and the PBF can cocrystallize in an isomorphic mode, despite the presence of the PBA comonomer. Such isomorphism was even found recently in PBS/PBF blends [73].…”