Biodegradable binary blends of poly (butylene succinate) or poly (ε-caprolactone) with poly (butylene succinate-ran-ε-caprolactone)copolymers: Crystallization behavior. (21st September 2022)

• Record Type: Journal Article
• Authors: Safari, Maryam; Pérez-Camargo, Ricardo A.; Ballester-Bayarri, Laura; Liu, Guoming; Mugica, Agurtzane; Zubitur, Manuela; Wang, Dujin; Müller, Alejandro J.
• Is Part Of: Polymer. Volume 256(2022)
• Publication Date: 2022-09-21
• Subjects: Poly (butylene succinate) -- Poly (ε-caprolactone) -- Poly (butylene succinate-ran-ε-caprolactone) copolymers -- Binary blends -- Crystallization behavior; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2022.125206
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Poly (butylene succinate) (PBS) and polycaprolactone (PCL) are two immiscible biocompatible and biodegradable polymers. Aiming to combine the properties of these biodegradable polymers, this work explores for the first time blending PBS or PCL with PBS- ran -PCL copolymers (BSx CLy ) at 75/25, 50/50, and 25/75 wt% compositions, with various copolymer contents: BS78 CL22, BS46 CL54, and BS15 CL85 . The crystallization behavior of these novel binary blends was systematically studied with non-isothermal and isothermal differential scanning calorimetry (DSC), polarized light optical microscopy (PLOM), and simultaneous wide- and small-angle X-ray scattering (WAXS and SAXS). All the blends displayed a miscible character in the amorphous state, judging by a single glass transition temperature, and in the melt state (as indicated by SAXS), but their miscibility in the crystalline state depends on the specific blend. In both PBS/BS78 CL22 and PCL/BS15 CL85 evidences of co-crystallization between the matrix and the crystallizable fraction of the copolymer were found. However, high comonomer exclusion, higher in the BS15 CL85 than in the BS78 CL22, greatly affects blend miscibility. Thus, the results show that the PBS/BS78 CL22 blend is miscible, in the crystalline state, at high PBS (homopolymer) content, i.e., 75/25 and 50/50 compositions, whereas its "counterpart", the PCL/BS15 CL85 displays partial miscibility, even for high PCL (homopolymer) content. For the 25/75 blends, i.e., copolymer-rich, the homopolymer addition favors the crystallization of the copolymer-rich component. Blending PBS or PCL with BS46 CL54 leads to blends that exhibit a much lower miscibility in the crystalline state than the blends prepared with BS or CL-rich copolymers, independently of the composition. But, interestingly, a novel behavior is found, since the BS46 CL54 copolymer can crystallize either in PBS type crystals or in PCL type crystals depending on the polymeric matrix (PCL or PBS). The PBS favors the crystallization of the BS component, while the PCL favors the crystallization of the CL component within the random copolymer. The crystallization behavior found in this work evidences the interactions of the PBS or PCL with the BSx CLy copolymer, representing a potential strategy to combine the properties of the PBS and PCL through blending. Graphical abstract: Image 1 Highlights: Combining properties of PBS and PCL by blending with their BSx CLy copolymers. Novel binary blends of PBS or PCL with BSx CLy copolymers in various compositions. Influence of the polymeric matrix on the BS46 CL54 crystallization. How exclusion/inclusion balance affects matrix - BSx CLy copolymer interactions. Tailoring properties of biodegradable binary blends: blend components and ratio.