Dual Actions of a Commercial Sorbitol Derivative on Crystallization Behavior of Poly(1,4-butylene adipate)

Abstract

Biodegradable poly­(1,4-butylene adipate) (PBA) has been highlighted of distinct polymorphism and receives extensive research by adding nucleating agents. Usually, only a single nucleating mechanism is proposed for each composite system, which should not be sufficient. In present work, 1,2,3-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)­methylene]-nonitol sorbitol (NX), a commercial sorbitol derivative, was incorporated into the PBA matrix to regulate the crystallization behavior. It is found that the non-isothermal crystallization temperature rises first and then declines, but the α-form crystal-forming ability becomes stronger with the increasing NX content, which is due to the limited solubility of NX in PBA. When NX is totally dissolved, the specific butterfly molecular shape of NX helps PBA chains form the gauche conformation, simultaneously promoting the crystallization rate and α crystal formation. However, once the NX content is ≥1%, crystallites of NX appear and play as physical cross-linking points for PBA chains; then, the mobility restriction becomes the major mechanism, which would slow down the crystallization rate but significantly enhance the formation of the α-form crystal-forming ability. PBA/NX composites possess a considerably lower degradation rate than neat PBA. Thus, this work demonstrates a novel additive of the dual mechanism to regulate the crystallization behavior and further the degradation rate of PBA.

Identifying, Quantifying, and Recovering a Sorbitol-Type Petrochemical Additive in Industrial Wastewater and Its Subsequent Application in a Polymeric Matrix as a Nucleating Agent

“…Among the various instrumental techniques employed to investigate Millad NX 8000 and its role as a nucleation/crystallization agent in polymers, Fourier transform infrared spectroscopy (FTIR) [ 25 , 26 ] and scanning electron microscopy (SEM) [ 26 ] have been utilized. Noteworthy studies, such as the comprehensive research conducted by Smith et al on the binary system of polypropylene and 1,3:2,4-bis(3,4-dimethylbenzylidene) sorbitol (DMDBS), have successfully determined the solubility of the additive using optical microscopy (OM) and differential scanning calorimetry (DSC).…”

Isothermal Kinetics of Poly(butylene adipate-co-butylene itaconate) Copolyesters with Ethylenediaminetetraacetic Acid

“…Aliphatic polyester, consisting of different lengths of the CH 2 group and ester bonds within the main chain or side chain, is a semicrystalline polymer and widely used as adhesives, fibers, films, scaffolds in biodegradable materials, and so on, which exhibits excellent flexibility in the polymer chain, mechanical properties, and biodegradability. − Poly­(butylene adipate) (PBA) is a typical aliphatic polyester that has been commercialized by the BASF company. − PBA is a polymorph polyester, and the crystal phases could be transformed into α-phase, β-phase, and an α/β complex under heat treatment. − The α-phase of PBA is associated with thermodynamic stability, while the β-phase is a metastable phase that can be induced into the α-phase via annealing procedures. The α-phase of PBA through annealing procedures could drive the transition behavior of crystal morphology and size, which leads to biodegradability.…”

“…13 The orientated PBS crystals resulted in excellent nucleation ability to induce the formation of α-phase PBA crystals in any crystallization situation. 23 Furthermore, a nucleation agent has been chosen to induce the transformation of the crystallization behavior between αand β-phase crystals, such as uracil, 14 poly(vinyl alcohol), 15 cyanuric acid, 16 anodic aluminum oxide, 17 anhydrous orotic acid, 18 oxalamide derivative, 19 sorbitol derivative, 21 and so on. Bao and colleagues have modified PBA with the end-functional Hbonding group, 2-ureido-4[1H]-pyrimidinone (UP), revealing that the UP-modified PBAs favored the formation of the thermally stable α-phase crystal at the same temperature, as well as lowering and broadening the temperature range for the βto α-phase crystal transition of PBA under heating processes.…”