Purpose: To synthesize and investigate polyhydroxyalkanoates (PHAs) with different monomer composition and percentages and polymer films prepared from them.
Results: Various PHAs: homopolymer poly-3-hydroxybutyrate P(3HB) and 2-, 3-, and 4-component copolymers comprising various combinations of 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), 4-hydroxybutyrate (4HB), and 3-hydroxyhexanoate (3HHx) monomers were synthesized under specialized conditions. Relationships were found between the monomer composition of PHAs and their molecular-weight and thermal properties and degree of crystallinity. All copolymers had decreased weight average molecular weights, M (to 390-600 kDa), and increased values of polydispersity (3.2-4.6) compared to the P(3HB). PHA copolymers showed different thermal behavior: an insignificant decrease in T and the presence of the second peak in the melting region and changes in parameters of crystallization and glass transition. At the same time, they retained thermostability, and the difference between T and T was at least 100-120 °C. Incorporation of 4HB, 3HV, and 3HHx monomer units into the 3-hydroxybutyrate chain caused changes in the amorphous to crystalline ratio and decreased the degree of crystallinity (C) to 20-40%. According to the degree to which the monomers reduced crystallinity, they were ranked as follows: 4HB - 3HHx - 3HV. A unique set of films was produced; their surface properties and physical/mechanical properties were studied as dependent on PHA composition; monomers other than 3-hydroxybutyrate were found to enhance hydrophilicity, surface development, and elasticity of polymer films.
Conclusion: An innovative set of PHA copolymers was synthesized and solution-cast films were prepared from them; the copolymers and films were investigated as dependent on polymer chemical composition. Results obtained in the present study contribute to the solution of a critical issue of producing degradable polymer materials.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ijbiomac.2021.04.008 | DOI Listing |
J Colloid Interface Sci
April 2025
College of Physics, Qingdao University, Qingdao 266071, China. Electronic address:
Polyacrylonitrile (PAN)-based composite solid electrolytes (CSEs) hold great promise in the practical deployment of solid lithium batteries (SLBs) owing to their high voltage stability but suffer from poor stability against Li-metal. Herein, a poly(1,3-dioxolane) (PDOL)-graphitic CN (g-CN, i.e.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
School of Chemistry, Dalian University of Technology, Dalian 116024 PR China. Electronic address:
The development of electrode materials for aqueous ammonium-ion supercapacitors (NH-SCs) has garnered significant attention in recent years. Poor intrinsic conductivity, sluggish electron transfer and ion diffusion kinetics, as well as structural degradation of vanadium oxides during the electrochemical process, pose significant challenges for their efficient ammonium-ion storage. In this work, to address the above issues, the core-shell VO·nHO@poly(3,4-ethylenedioxithiophene) composite (denoted as VOH@PEDOT) is designed and prepared by a simple agitation method to boost the ammonium-ion storage of VO·nHO (VOH).
View Article and Find Full Text PDFVat photopolymerization (VPP) is an additive manufacturing method that requires the design of photocurable resins to act as feedstock and binder for the printing of parts, both monolithic and composite. The design of a suitable photoresin is costly and time-consuming. The development of one formulation requires the consumption of kilograms of costly materials, weeks of printing and performance testing, as well as the need to have developers with the expertise and knowledge of the materials used, making the development process cost thousands.
View Article and Find Full Text PDFMolecules
January 2025
Department of Chemistry, University of Connecticut, Storrs, CT 06269, USA.
Optically responsive materials are applied in sensing, actuators, and optical devices. One such class of material is dye-doped liquid crystal polymers that self-assemble into cholesteric mesophases that reflect visible light. We report here the synthesis and characterization of a family of linear and mildly crosslinked terpolymers prepared by the ROMP of norbornene-based monomers.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Institute of New Energy Material Chemistry, School of Materials Science and Engineering, Nankai University, Tianjin 300350, China.
Eutectic-based polymer electrolytes have emerged as promising solid electrolytes because of their ionic liquid-like properties, while modifications are essential to further increase their ionic conductivity at room temperature and solve their compatibility with lithium anode. In this work, an in situ polymerized composite electrolyte is modified by the addition of fluoroethylene carbonate (FEC) whose beneficial effect is systematically investigated in different contents. Poly(ethylene glycol) diacrylate (PEGDA), deep eutectic solvent (LiTFSI:-methylacetamide = 1:3), and alumina fiber work as the monomer, solvent, and three-dimensional skeleton, respectively.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!