biodegradable polymers; long chain branching; molecular engineering; polymer synthesis; rheology; Branched architecture; Long chains; Long-chain branching; Melt strength; Molecular engineering; Poly (butylenes succinate); Polybutylene succinate; Polymer synthesis; Strength property; Terephthalate; Chemical Engineering (all); Physical and Theoretical Chemistry; Polymers and Plastics; Organic Chemistry; Materials Chemistry; General Chemical Engineering
Abstract :
[en] Highly biobased poly(butylene succinate-co-terephthalate) (PBST) with processing temperatures close to those of commodity polymers (160–180°C) and long-chain branched architectures (LCB) are synthesized by different strategies. Their rheological properties are investigated, in particular their melt strength properties. A two-step synthesis route is first proposed based on linear LCBs produced by polycondensation followed by reactive extrusion with an epoxy-based multifunctional agent Joncryl® at concentrations up to 2 wt%. A one-step synthesis strategy is also developed using glycerol as a branching agent, introduced at a low concentration (0.5 wt%) directly during the PBST polycondensation process. The molecular weights, LCB structures, and thermal properties are determined by triple detection size exclusion chromatography and differential scanning calorimetry. For PBSTs synthesized in two steps, gelation takes place simultaneously with the branching reactions. However, a concentration of Joncryl® close to 2 wt% is required to improve the melt strength properties, with strain hardening effects under elongation conditions. Interestingly, PBSTs synthesized by in-situ addition of glycerol show remarkable melt strength and a high melt stabilization process. Dynamic rheology investigations allow attributing these effects to statistical/ho-mogeneous gel-free LCB architectures obtained during reactive extrusion without any additional post-processing. The effec-tiveness of approaches to easily improve the melt strength of highly biobased aliphatic-aromatic copolyesters (theoretical biobased content up to 85%) and to eliminate extrusion defects/instabilities in PBSTs is thus demonstrated, allowing the pos-sibility of expanding the industrial application domains of these polymers in packaging and sustainable applications.
Disciplines :
Chemistry
Author, co-author :
Yousfi, Mohamed; IMT Nord Europe, Institut Mines-Télécom, Univ. Lille, Centre for Materials and Processes, Lille, France ; Univ Lyon, CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, Villeurbanne, France
Samuel, Cédric; IMT Nord Europe, Institut Mines-Télécom, Univ. Lille, Centre for Materials and Processes, Lille, France
Dadouche, Tarek; Univ Lyon, CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, Villeurbanne, France
Mincheva, Rosica ; Université de Mons - UMONS > Faculté des Science > Service des Matériaux Polymères et Composites
Lacrampe, Marie-France; Univ Lyon, CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, Villeurbanne, France
Language :
English
Title :
Long-chain branched poly(butylene succinate-co-terephthalate) copolyesters: Impact of (reactive) synthesis strategies on melt strength properties
Publication date :
March 2023
Journal title :
eXPRESS Polymer Letters
ISSN :
1788-618X
Publisher :
BME-PT and GTE
Volume :
17
Issue :
3
Pages :
300 - 316
Peer reviewed :
Peer Reviewed verified by ORBi
Research unit :
S816 - Matériaux Polymères et Composites
Research institute :
Matériaux
Funding text :
The authors gratefully acknowledge Ms. Agnes Crepet from the University Claude Bernard Lyon 1 and Mr. Ahmed Belhadj from INSA Lyon for their experimental support and recommendations regarding the SEC-MALS and gel determination measurements. The authors acknowledge the European Com-munity (FEDER funds) and the International Campus on Safety and Intermodality in Transportation (CISIT, France) as well as the Hauts-de-France Region (France) for the fi-nancial contribution of the dynamic rheometer and extrusion machines.
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