Porous carbon derived from biomass-based polymers: Innovative applications in supercapacitors

Chinese Chemical Letters, Journal Year: 2025, Volume and Issue: unknown, P. 110860 - 110860

Published: Jan. 1, 2025

Language: Английский

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Achieving Exceptional Thermal and Hydrolytic Resistance in Chemically Circular Polyesters via In‐Chain 1,3‐Cyclobutane Rings

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(24)

Published: April 8, 2024

Abstract Polyesters, a highly promising class of circular polymers for achieving closed‐loop sustainable plastic economy, inherently exhibit material stability defects, especially in thermal and hydrolytic instability. Here, we introduce polyesters, P(4 R ‐BL) (R=Ph, Bu), featuring conformationally rigid 1,3 ‐ cyclobutane rings the backbone. These polyesters not only superior thermostability ( T d,5% =376–380 °C) but also demonstrate exceptional resistance with good integrity even after 1 year basic acidic aqueous solutions, distinguishing themselves from typical counterparts. Tailoring flexibility side group enables controlled mechanical performance Ph Bu to rival durable syndiotactic polystyrene (SPS) low‐density polyethylene (LDPE), respectively. Significantly, despite their high stability, both can be effectively depolymerized into pristine monomers, establishing life cycle.

Language: Английский

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Crystal Structure of Atactic and Isotactic Poly(3-hydroxy-2,2-dimethylbutyrate): A Chemically Recyclable Poly(hydroxyalkanoate) with Tacticity-Independent Crystallinity

Macromolecules, Journal Year: 2024, Volume and Issue: 57(9), P. 4357 - 4373

Published: April 19, 2024

The crystal structures of isotactic and atactic poly(3-hydroxy-2,2-dimethylbutyrate) (P3H(Me)2B) are presented. Samples P3H(Me)2B (at-(R/S)-P3H(Me)2B) the R S enantiomers (it-(R)-P3H(Me)2B it-(S)-P3H(Me)2B, respectively) have been synthesized by ring opening polymerization racemic chiral dimethyl-butyrolactones employing a superbase catalyst. A 1:1 mixture two (it-(R,S)-P3H(Me)2B) has also prepared. Both pure enantiomer polymers crystallize showing identical diffraction patterns, indicating crystallization in same crystalline form structure. it-(R,S)-P3H(Me)2B crystallizes giving pattern. This is one few examples an polymer despite configurational disorder probably it first structurally confirmed example fascinating tacticity-independent crystallinity explains remarkable thermal mechanical behaviors P3H(Me)2B, which thermally stable melt-processable chemically recyclable to monomer. structure resolved analysis X-ray powder fiber oriented fibers, combined with conformational based on methods density functional theory. ordered it-(R)-P3H(Me)2B (or it-(S)-P3H(Me)2B) described chains nearly trans-planar conformation chain axis 4.7 Å packed orthorhombic unit cell axes = 13.30 Å, b 9.99 c 4.75 according space groups P21212 or P212121. at-(R/S)-P3H(Me)2B having only slightly larger axis, 13.94 10.03 characterized disordered succession monomers distorted that keeps straight periodicity enantiomer. proposed model polymer. is, therefore, packing both P212121 achiral Pna21 Pnn2.

Language: Английский

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Kinetic Resolution Polymerization Enabled Chemical Synthesis of Perfectly Isotactic Polythioesters

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(29)

Published: April 29, 2024

Abstract Isotactic polythioesters (PTEs) that are thioester analogs to natural polyhydroxyalkanoates (PHAs) have attracted growing attention due their distinct properties. However, the development of chemically synthetic methods for preparing isotactic PTEs has long been an intricate endeavour. Herein, we report successful synthesis perfectly via stereocontrolled ring‐opening polymerization. This binaphthalene‐salen aluminium (SalBinam‐Al) catalyst promoted a robust polymerization rac ‐α‐substituted‐β‐propiothiolactones ( ‐BTL and ‐PTL) with highly kinetic resolution, affording P(BTL) P(PTL) M n up 276 kDa. Impressively, formed supramolecular stereocomplex improved thermal property T m =204 °C). Ultimately, this resolution enabled facile isolation enantiopure S )‐BTL, which could efficiently convert important pharmaceutical building block )‐2‐benzyl‐3‐mercapto‐propanoic acid. served as tough ductile material comparable commercialized polyolefins. system allowed access PTEs, establishing powerful platform discovery sustainable plastics.

Language: Английский

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Polyhydroxyalkanoates in emerging recycling technologies for a circular materials economy

Materials Advances, Journal Year: 2024, Volume and Issue: 5(17), P. 6690 - 6701

Published: Jan. 1, 2024

This paper discusses the scale-up feasibility and industrial adoption of polyhydroxyalkanoates (PHAs), emphasizing need to link PHA development with recycling technologies highlighting strategies for designing PHAs closed-loop recycling.

Language: Английский

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Carbon Recycling of High Value Bioplastics: A Route to a Zero-Waste Future

Polymers, Journal Year: 2024, Volume and Issue: 16(12), P. 1621 - 1621

Published: June 7, 2024

Today, 98% of all plastics are fossil-based and non-biodegradable, globally, only 9% recycled. Microplastic nanoplastic pollution is just beginning to be understood. As the global demand for sustainable alternatives conventional continues rise, biobased biodegradable have emerged as a promising solution. This review article delves into pivotal concept carbon recycling pathway towards achieving zero-waste future through production utilization high-value bioplastics. The comprehensively explores current state bioplastics (biobased and/or materials), emphasizing importance carbon-neutral circular approaches in their lifecycle. chiefly used low-value applications, such packaging single-use items. sheds light on value-added like longer-lasting components products, demanding properties, which increasingly being deployed. Based waste hierarchy paradigm—reduce, reuse, recycle—different use cases end-of-life scenarios materials will described, including technological options recycling, from mechanical chemical methods. A special emphasis common bioplastics—TPS, PLA, PHAs—as well discussion composites, provided. While it acknowledged that (waste) crisis stems largely mismanagement, needs stated radical solution must come core material side, intrinsic properties polymers formulations. manner cascaded bioplastics, labeling, legislation, technologies, consumer awareness can contribute topics this article.

Language: Английский

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Upcycling of recycled polyethylene for rotomolding applications via dicumyl peroxide crosslinking

Journal of Applied Polymer Science, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 3, 2024

Abstract Polyethylene (PE), including high‐density polyethylene (HDPE) and low‐density (LDPE), makes up a significant part of post‐consumer plastics in municipal solid waste, presenting challenges for traditional recycling methods due to wide range melt flow properties poor interfacial adhesion between the different resin, which often leads low quality products (downcycling). In this study, method is proposed modify molecular structure PE (rHDPE rLDPE) their blends by using straightforward organic peroxide crosslinking technique with 1 phr dicumyl (DCP). Different rHDPE/rLDPE blend weight ratios (0/100, 20/80, 40/60, 50/50, 60/40, 80/20, 100/0) were prepared combination co‐rotating twin‐screw extrusion pulverization. The final parts produced via rotomolding where both forming processes occurred concurrently. Subsequently, materials characterized terms chemical, thermal, mechanical properties. It was found that tensile strength (228%), modulus (345%), flexural (145%), (251%) increased 80% wt. rHDPE (x‐rHDPE). Conversely, gel content 17%, thermal resistance 37.2%, impact 93% rLDPE (x‐rLDPE). can be concluded balance occurs as addition DCP improved blends. This innovative approach represents simple upcycle mixed (PE) streams, especially applications. also offers promising avenues sustainable waste management material reuse.

Language: Английский

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High–performance, multifunctional sustainable polycarbonates and application in negative–type photoresists

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: 505, P. 159337 - 159337

Published: Jan. 7, 2025

Language: Английский

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Circular Polymer Designed by Regulating Entropy: Spiro-Valerolactone-Based Polyesters with High Gas Barriers and Adhesion Strength

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 27, 2025

Enthalpy is often the focal point when designing monomers for polymer circularity, but much less explored on how entropy can be exploited to create polymers with synergistic circularity and properties. Here, we design a series of spiro-lactones (SLs) closed-chain cycloalk(en)yl substituents at α,α-position δ-valerolactone (δVL), which, combined parent δVL gem-α,α-dialkyl-substituted open-chain alkyl groups, provide desired platform exploring circular by focusing change polymerization. These SLs exhibit finely balanced (de)polymerizability that regulated chiefly differentiation, allowing both facile synthesis polyester PSLs (Mn up 1000 kg mol–1) in living fashion selective depolymerization completely recover under mild conditions (using recyclable catalyst 100 °C). One such PSL semicrystalline (Tm = 134 °C), strong (ultimate strength 43 MPa), hard (modulus 1.85 GPa), modestly flexible. notable mechanical properties are bolstered its superior barriers oxygen moisture permeation compared common packaging materials. In addition, this postfunctionalized OH-containing shows higher adhesion than comparative commercial adhesives.

Language: Английский

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Circular polyester design by gem-heterodisubstitution: valerolactone-based polymers with high ductility and excellent strength

Polymer Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A series of α,α-heterodisubstituted δ-valerolactones (VL R1,R2 ) provide a desired platform for exploring circular polymer design by focusing on the asymmetric substitution monomers.

Language: Английский

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