145 results match your criteria comonomer composition

Understanding of how the properties of medical grade lactide based copolymer scaffolds influence adipose tissue regeneration: Sterilization and a systematic in vitro assessment.

Mater Sci Eng C Mater Biol Appl 2021 May 18;124:112020. Epub 2021 Mar 18.

Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Teknikringen 56-58, SE 10044 Stockholm, Sweden. Electronic address:

Aliphatic polyesters are the synthetic polymers most commonly used in the development of resorbable medical implants/devices. Various three-dimensional (3D) scaffolds have been fabricated from these polymers and used in adipose tissue engineering. However, their systematic evaluation altogether lacks, which makes it difficult to select a suitable degradable polymer to design 3D resorbable implants and/or devices able to effectively mimic the properties of adipose tissue. Read More

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Preparation and Properties of Benzylsulfonyl-Containing Silicone Copolymers via Ring-opening Copolymerization of Macroheterocyclosiloxane and Cyclosiloxane.

Chemistry 2021 Mar 30. Epub 2021 Mar 30.

Key Laboratory of Special Functional Aggregated Materials & Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education Department, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250199, P. R. China.

Ring-opening copolymerization (ROCP) of benzylsulfonyl macroheterocyclosiloxane (BSM) and five different cyclosiloxanes was systematically investigated. A general approach for the synthesis of benzylsulfonyl-containing silicone copolymers with various substituents, including methyl, vinyl, ethyl, and phenyl, was developed herein. A series of copolymers with variable incorporation (from 6 % to 82 %) of BSM were obtained by modifying the comonomer feed ratio and using KOH as the catalyst in a mixed solvent of dimethylformamide and toluene. Read More

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Injectable oligomer-cross-linked gelatine hydrogels anhydride-amine-conjugation.

J Mater Chem B 2021 03;9(9):2295-2307

Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, Eilenburger Straße 15 a, 04317 Leipzig, Germany and Institute of Pharmaceutics and Biopharmaceutics, Heinrich-Heine-Universität, Universitätsstraße 1, Düsseldorf, 40225 Düsseldorf, Germany.

Injectable gelatine-based hydrogels are valuable tools for drug and cell delivery due to their extracellular matrix-like properties that can be adjusted by the degree of cross-linking. We have established anhydride-containing oligomers for the cross-linking of gelatine via anhydride-amine-conjugation. So far, this conversion required conditions not compatible with cell encapsulation or in vivo injection. Read More

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Control of Particle Size in the Self-Assembly of Amphiphilic Statistical Copolymers.

Macromolecules 2021 Feb 22;54(3):1425-1440. Epub 2021 Jan 22.

Department of Chemistry, The University of Sheffield, Dainton Building, Sheffield S3 7HF, U.K.

A range of amphiphilic statistical copolymers is synthesized where the hydrophilic component is either methacrylic acid (MAA) or 2-(dimethylamino)ethyl methacrylate (DMAEMA) and the hydrophobic component comprises methyl, ethyl, butyl, hexyl, or 2-ethylhexyl methacrylate, which provide a broad range of partition coefficients (log ). Small-angle X-ray scattering studies confirm that these amphiphilic copolymers self-assemble to form well-defined spherical nanoparticles in an aqueous solution, with more hydrophobic copolymers forming larger nanoparticles. Varying the nature of the alkyl substituent also influenced self-assembly with more hydrophobic comonomers producing larger nanoparticles at a given copolymer composition. Read More

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February 2021

A new polymer-excipient for ethanol-resistant, sustained-release oral dosage forms.

Drug Deliv Transl Res 2021 Jan 19. Epub 2021 Jan 19.

Evonik Operations GmbH, Kirschenallee, 64293, Darmstadt, Germany.

The use of alcoholic beverages can cause uncontrolled release of drugs from sustained-release solid oral dosage forms and pose severe risks to patient health. The aim of this work was to design a new polymeric excipient with ethanol resistance inherent to the polymer. Polymers were systematically designed, manufactured via emulsion polymerization, and fully characterized. Read More

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January 2021

Application of Monopotassium Dipropylene Glycoxide for Homopolymerization and Copolymerization of Monosubstituted Oxiranes: Characterization of Synthesized Macrodiols by MALDI-TOF Mass Spectrometry.

Polymers (Basel) 2020 Nov 26;12(12). Epub 2020 Nov 26.

Institute Materials Engineering, University of Silesia, 40-007 Katowice, Poland.

Monopotassium dipropylene glycoxide, activated by a 18-crown-6 cation complexing agent (K-DPG/L, where DPG (dipropylene glycol) is a mixture of isomers) was used as an effective initiator of the homopolymerization and copolymerization of several monosubstituted oxiranes, i.e., propylene oxide (PO), 1. Read More

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November 2020

Structural and Thermal Properties of Ethylene-Norbornene Copolymers Obtained Using Vanadium Homogeneous and SIL Catalysts.

Polymers (Basel) 2020 Oct 22;12(11). Epub 2020 Oct 22.

Faculty of Chemistry, Opole University, Oleska 48, 45-052 Opole, Poland.

The series of ethylene-norbornene (E-NB) copolymers was obtained using different vanadium homogeneous and supported ionic liquid (SIL) catalyst systems. The C and H NMR (carbon and proton nuclear magnetic resonance spectroscopy) together with differential scanning calorimetry (DSC) were applied to determine the composition of copolymers such as comonomer incorporation (), monomer dispersity (), monomer reactivity ratio (), sequence length of ethylene ( and tetrad microblock distributions. The relation between the type of catalyst, reaction conditions and on the other hand, the copolymer microstructure, chain termination reaction analyzed by the type of unsaturation are discussed. Read More

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October 2020

Effect of Poly(vinyl butyral) Comonomer Sequence on Adhesion to Amorphous Silica: A Coarse-Grained Molecular Dynamics Study.

ACS Appl Mater Interfaces 2020 Oct 6;12(42):47879-47890. Epub 2020 Oct 6.

Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States.

Modulating a comonomer sequence, in addition to the overall chemical composition, is the key to unlocking the true potential of many existing commercial copolymers. We employ coarse-grained molecular dynamics (MD) simulations to study the behavior of random-blocky poly(vinyl butyral--vinyl alcohol) (PVB) melts in contact with an amorphous silica surface, representing the interface found in laminated safety glass. Our two-pronged coarse-graining approach utilizes both macroscopic thermophysical data and all-atom MD simulation data. Read More

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October 2020

Iterative RAFT-Mediated Copolymerization of Styrene and Maleic Anhydride toward Sequence- and Length-Controlled Copolymers and Their Applications for Solubilizing Lipid Membranes.

Biomacromolecules 2020 08 30;21(8):3287-3300. Epub 2020 Jul 30.

Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.

The use of poly(styrene--maleic acid) (SMA) for the solubilization of lipid membranes and membrane proteins is becoming more widespread, and with this, the need increases to better understand the chemical properties of the copolymer and how these translate into membrane solubilization properties. SMA comes in many different flavors that include the ratio of styrene to maleic acid, comonomer sequence distribution, average chain length, dispersity, and potential chemical modifications. In this work, the synthesis and membrane active properties are described for 2:1 (periodic) SMA copolymers with varying from ∼1. Read More

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Effect of the Crystallization Conditions on the Exclusion/Inclusion Balance in Biodegradable Poly(butylene succinate--butylene adipate) Copolymers.

Biomacromolecules 2020 08 24;21(8):3420-3435. Epub 2020 Jul 24.

POLYMAT and Polymer Sciences and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal 3, 20018 Donostia-San Sebastián, Spain.

Biomedical applications of polymers require precise control of the solid-state structure, which is of particular interest for biodegradable copolymers. In this work, we evaluated the influence of crystallization conditions on the comonomer exclusion/inclusion balance of biodegradable poly(butylene succinate--butylene adipate) (PBSA) isodimorphic random copolymers. Regardless of the crystallization conditions, the copolymers retain their isodimorphic character, displaying a pseudo-eutectic behavior with crystallization in the entire composition range. Read More

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Chemical Structure and Physical Properties of Heat-cured Poly(methyl methacrylate) Resin Processed with Cycloaliphatic Comonomer: An Study.

J Contemp Dent Pract 2020 Mar 1;21(3):285-290. Epub 2020 Mar 1.

Department of Prosthodontics and Crown and Bridge, Vinayaka Mission's Sankarachariyar Dental College and Hospital, Salem, Tamil Nadu, India.

Aim: The purpose of this research is to chemically characterize polymethyl methacrylate (PMMA) processed with 10% and 20% (v/v) tricyclodecane dimethanol diacrylate (TCDDMDA) comonomer. It also aimed to assess the degree of conversion (DC) and glass transition temperature () of the formed copolymers.

Materials And Methods: The experimental groups were processed with the TCDDMDA comonomer (10% and 20% v/v), whereas the control group was processed only with the methyl methacrylate monomer. Read More

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Advanced Liquid Chromatography of Polyolefins Using Simultaneous Solvent and Temperature Gradients.

Anal Chem 2020 05 1;92(10):7325-7333. Epub 2020 May 1.

Department of Chemistry and Polymer Science, Stellenbosch University, P. O. Box X1,7602 Stellenbosch, South Africa.

Olefin copolymers are complex polymer materials that exhibit multiple distributions in molecular properties such as molar mass, chemical composition, and branching. To address the multivariate molecular compositions, chromatographic protocols have been developed that synergistically combine solvent and temperature gradients. As representative examples, blends of olefin copolymers have been fractionated on porous graphitic carbon stationary phases. Read More

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Photodynamic Control of the Chain Length in Supramolecular Polymers: Switching an Intercalator into a Chain Capper.

J Am Chem Soc 2020 04 20;142(13):6295-6303. Epub 2020 Mar 20.

Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.

Supramolecular systems are intrinsically dynamic and sensitive to changes in molecular structure and external conditions. Because of these unique properties, strategies to control polymer length, composition, comonomer sequence, and morphology have to be developed for sufficient control over supramolecular copolymerizations. We designed photoresponsive, mono acyl hydrazone functionalized benzene-1,3,5-tricarboxamide () monomers that play a dual role in the coassembly with achiral alkyl BTAs (). Read More

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Transparent, High-Strength, and Shape Memory Hydrogels from Thermo-Responsive Amino Acid-Derived Vinyl Polymer Networks.

Macromol Rapid Commun 2020 Apr 20;41(7):e1900650. Epub 2020 Feb 20.

Department of Molecular Chemistry & Biochemistry, Faculty of Science & Engineering, Doshisha University, Kyotanabe, Kyoto, 610-0321, Japan.

Herein, the formation of unique shape-memory hydrogels that are composed of thermo-responsive amino-acid-derived vinyl polymer networks is reported; these are readily prepared by radical copolymerization of N-acryloyl glycinamide with commercially available cross-linkers, namely, methylenebis(acrylamide) and poly(ethylene glycol) diacrylate. These hydrogels are transparent (>90% transmittance at 600 nm) and are comprised of 97-70 wt% water. Furthermore, these contain both chemical and physical cross-linkages that are based on the multiple hydrogen bonds attained via amino acid units; this composition is aimed at generating opposing stimuli-responsive characters, namely, chemically stable and thermo-sensitive properties. Read More

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Thermal Analysis and Crystal Structure of Poly(Acrylonitrile-Co-Itaconic Acid) Copolymers Synthesized in Water.

Polymers (Basel) 2020 Jan 16;12(1). Epub 2020 Jan 16.

Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China.

The composition and structure of polyacrylonitrile (PAN) precursors play an important role during thermal stabilization, which influences the properties of the resulting carbon fibers. In this paper, PAN homopolymer and PAN-itaconic (IA) copolymers with different IA contents were synthesized by aqueous phase precipitation polymerization. The effects of IA content on the structure and thermal properties were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Read More

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January 2020

Biocompatibility and thermodynamic properties of PEGDA and two of its copolymer.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:1093-1096

During the last years substantial effort was taken in order to provide an effective and safe pharmacotherapy that can be adjusted to the individual needs of patients. Stereolithography is a simple and accurate additive manufacturing technology. According to these characteristics, it may offer unique opportunities for the industrial fabrication of structured drug delivery systems (DDS), which can be tailored to individual needs. Read More

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Controlling the Isothermal Crystallization of Isodimorphic PBS--PCL Random Copolymers by Varying Composition and Supercooling.

Polymers (Basel) 2019 Dec 20;12(1). Epub 2019 Dec 20.

POLYMAT and Polymer Science and Technology Department, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal 3, 20018 Donostia-San Sebastián, Spain.

In this work, we study for the first time, the isothermal crystallization behavior of isodimorphic random poly(butylene succinate)--poly(ε-caprolactone) copolyesters, PBS--PCL, previously synthesized by us. We perform nucleation and spherulitic growth kinetics by polarized light optical microscopy (PLOM) and overall isothermal crystallization kinetics by differential scanning calorimetry (DSC). Selected samples were also studied by real-time wide angle X-ray diffraction (WAXS). Read More

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December 2019

Hydrolytic Degradation of Comb-Like Graft Poly (Lactide-co-Trimethylene Carbonate): The Role of Comonomer Compositions and Sequences.

Polymers (Basel) 2019 Dec 6;11(12). Epub 2019 Dec 6.

State Key Laboratory of Fine Chemicals, Department of Polymer Science and Engineering, Liaoning Key Laboratory of Polymer Science and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.

The effect of sequence on copolymer properties is rarely studied, especially the degradation behavior of the biomaterials. A series of linear-comb block, gradient, random copolymers were successfully achieved using hydroxylated polybutadiene as the macroinitiator by simple ring-opening polymerization of l-lactide (l-LA) and 1,3-trimethylene carbonate (TMC). The hydrolytic degradation behaviors of the copolymers were systemically evaluated by using nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), differential scanning calorimeter (DSC), and scanning electron microscopy (SEM) to illustrate the influences of comonomer compositions and sequence structures. Read More

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December 2019

Tetrapolymer Network Hydrogels via Gum Ghatti-Grafted and N-H/C-H-Activated Allocation of Monomers for Composition-Dependent Superadsorption of Metal Ions.

ACS Omega 2018 Sep 6;3(9):10692-10708. Epub 2018 Sep 6.

Advanced Polymer Laboratory, Department of Polymer Science and Technology, and Department of Leather Technology, Government College of Engineering and Leather Technology (Post-Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake, Kolkata 700106, West Bengal, India.

Herein, gum ghatti (GGTI)--[sodium acrylate (SA)--3-(-(4-(4-methyl pentanoate))acrylamido)propanoate (NMPAP)--4-(acrylamido)-4-methyl pentanoate (AMP)---isopropylacrylamide (NIPA)] (i.e., GGTI--TetraP), a novel interpenetrating tetrapolymer network-based sustainable hydrogel, possessing extraordinary physicochemical properties and excellent recyclability, has been synthesized via grafting of GGTI and in situ strategic protrusion of NMPAP and AMP during the solution polymerization of SA and NIPA, through systematic multistage optimization of ingredients and temperature, for ligand-selective superadsorption of hazardous metal ions (M(II)), such as Sr(II), Hg(II), and Cu(II). Read More

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September 2018

Visualization and design of the functional group distribution during statistical copolymerization.

Nat Commun 2019 08 13;10(1):3641. Epub 2019 Aug 13.

Ghent University, Laboratory for Chemical Technology (LCT), Technologiepark 125, B-9052, Gent, Belgium.

Even though functional copolymers with a low percentage of functional comonomer units (up to 20 mol%) are widely used, for instance for the development of polymer therapeutics and hydrogels, insights in the functional group distribution over the actual chains are lacking and the average composition is conventionally used to describe the functionalization degree. Here we report the visualization of the monomer distribution over the different polymer chains by a synergetic combination of experimental and theoretical analysis aiming at the construction of functionality-chain length distributions (FUNC-CLDs). A successful design of the chemical structure of the comonomer pair, the initial functional comonomer amount (13 mol%), and the temperature (100 °C) is performed to tune the FUNC-CLD of copoly(2-oxazoline)s toward high functionalization degree for both low (100) and high (400) target degrees of polymerization. Read More

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Sequencing of Side-Chain Liquid Crystalline Copolymers by Matrix-Assisted Laser Desorption/Ionization Tandem Mass Spectrometry.

Polymers (Basel) 2019 Jul 1;11(7). Epub 2019 Jul 1.

Department of Chemistry, The University of Akron, Akron, OH 44325, USA.

Polyether based side-chain liquid crystalline (SCLC) copolymers with distinct microstructures were prepared using living anionic polymerization techniques. The composition, end groups, purity, and sequence of the resulting copolymers were elucidated by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and tandem mass spectrometry (MS/MS). MALDI-MS analysis confirmed the presence of (CH)CO- and -H end groups at the initiating (α) and terminating (ω) chain end, respectively, and allowed determination of the molecular weight distribution and comonomer content of the copolymers. Read More

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Miniemulsion RAFT Copolymerization of MMA with Acrylic Acid and Methacrylic Acid and Bioconjugation with BSA.

Nanomaterials (Basel) 2019 May 31;9(6). Epub 2019 May 31.

Programa de Engenharia Química/COPPE-Universidade Federal do Rio de Janeiro, Cidade Universitária 68502, Rio de Janeiro-21941-972 RJ, Brazil.

Polymerization through reversible addition-fragmentation chain-transfer (RAFT) polymerization has been extensively employed for the production of polymers with controlled molar mass, complex architectures and copolymer composition distributions intended for biomedical and pharmaceutical applications. In the present work, RAFT miniemulsion copolymerizations of methyl methacrylate with acrylic acid and methacrylic acid were conducted to prepare hydrophilic polymer nanoparticles and compare cell uptake results after bioconjugation with bovine serum albumin (BSA), used as a model biomolecule. Obtained results indicate that the RAFT agent 2-cyano-propyl-dithiobenzoate allowed for successful free radical controlled methyl methacrylate copolymerizations and performed better when methacrylic acid was used as comonomer. Read More

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Degradable and Thermosensitive Microgels Synthesized via Simultaneous Quaternization and Siloxane Condensation.

Langmuir 2019 05 23;35(18):6145-6153. Epub 2019 Apr 23.

Department of Chemistry , Zhejiang Sci-Tech University , Hangzhou 310018 , China.

Degradable and thermosensitive microgels were successfully prepared via simultaneous quaternization and siloxane condensation during surfactant-free emulsion polymerization, with N-vinylcaprolactam as the main monomer and 1-vinylimidazole (VIM) as the comonomer, in the presence of (3-bromopropyl)trimethoxysilane (BPTMOS). The formation mechanism of cross-linking network was attributed to the hydrolysis and condensation of the methoxysilyl groups of BPTMOS and the quaternization of imidazole moiety of VIM by the bromine group of BPTMOS, leading to the microgels. The microgels were spherical in shape with a narrow size distribution, stable in an acidic buffer solution, but degradable in neutral and alkaline solutions. Read More

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Crystalline Structures and Structural Transitions of Copolyamides Derived from 1,4-Diaminobutane and Different Ratios of Glutaric and Azelaic Acids.

Polymers (Basel) 2019 Mar 27;11(4). Epub 2019 Mar 27.

Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Escola d'Enginyeria de Barcelona Est-EEBE, c/Eduard Maristany 10-14, 08019 Barcelona, Spain.

Copolyamides derived from even 1,4-butanediamine and different mixtures of odd dicarboxylic acids with a great difference in the number of methylene groups (i.e., glutaric and azelaic acids with 3 and 7 groups, respectively) have been synthesized, characterized and structurally studied. Read More

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Synthesis, microstructure and mechanical properties of partially biobased biodegradable poly(ethylene brassylate-co-ε-caprolactone) copolyesters.

J Mech Behav Biomed Mater 2019 03 18;91:255-265. Epub 2018 Dec 18.

State Key Laboratory of Fine Chemicals, Department of Polymer Science and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China. Electronic address:

High-molecular-weight poly(ethylene brassylate-co-ε-caprolactone) copolyesters within a wide composition range were prepared via triphenyl bismuth catalyzed copolymerization of ethylene brassylate (EB) and ε-caprolactone (ε-CL) in bulk. Microstructural analysis of the resulting copolyesters demonstrated that the comonomer units were completely random distribution. DSC and WAXD recognized that the copolyesters cocrystallize within the lattices analogous to either of the parent homopolymers. Read More

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Effect of Selected Comonomers on the Transition Temperature of Thermosensitive NIPA Derivatives Synthesized with an Anionic Initiator.

J Nanosci Nanotechnol 2019 May;19(5):3049-3056

Department of Physical Chemistry, Pharmaceutical Faculty, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland.

The present study evaluates the effect of the cationic initiator on the hydrodynamic diameter of copolymers of -isopropylacrylamide nanogels synthesized via a surfactant-free precipitation polymerization at 70 °C in the presence of the cationic initiator 2,2'-azobis[2- methylpropionamidine] dihydrochloride. Three types of polymeric nanoparticles were synthesized using '-methylenebisacrylamide as a crosslinker. The first batch was used as a reference. Read More

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Modification of Poly(ethylene 2,5-furandicarboxylate) with Biobased 1,5-Pentanediol: Significantly Toughened Copolyesters Retaining High Tensile Strength and O Barrier Property.

Biomacromolecules 2019 01 3;20(1):353-364. Epub 2018 Dec 3.

Laboratory of Polymeric and Composite Materials (LPCM), Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons , Mons 7000 , Belgium.

Poly(ethylene 2,5-furandicarboxylate) (PEF) is a biobased polyester characterized by high gas barrier properties as well as high tensile modulus and strength, but poor toughness. Toughening PEF without sacrificing its modulus, strength and gas barrier performance is a great challenge for PEF modification. In this study, high molecular weight random poly(ethylene- co-1,5-pentylene 2,5-furandicarboxylate)s (PEPeFs) were synthesized via melt copolycondensation of 2,5-furandicarboxylic acid (FDCA), ethylene glycol (EG) and 1,5-pentanediol (PeDO), a cheap, biobased and commercially available odd-carbon comonomer. Read More

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January 2019

Tuning the Phase Transition from UCST-Type to LCST-Type by Composition Variation of Polymethacrylamide Polymers.

Macromol Rapid Commun 2018 Dec 3;39(24):e1800640. Epub 2018 Oct 3.

Macromolecular Chemistry II and Bayreuth Center for Colloids and Interfaces, Universitätsstrasse 30, 95440, Bayreuth, Germany.

Polymethacrylamide copolymers with hydrophobic N-substituted acrylamides, such as N-cyclohexylacrylamide and N-tert-butylacrylamide, are rare examples of polymers showing composition-dependent thermoresponsive behavior in water. They show unexpected behavior different from the conventional copolymers of a thermoresponsive polymer with hydrophobic comonomers. On increasing the amount of the hydrophobic comonomer in the polymer, there is a change from UCST-type phase behavior to complete solubility, followed by compositions showing LCST-type transition and insolubility in water (U-S-L-I-type change). Read More

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December 2018

Efficient removal of cationic dye mixtures from water using a bio-composite adsorbent optimized with response surface methodology.

Carbohydr Polym 2018 Nov 29;200:305-320. Epub 2018 Jul 29.

Department of Polymer Science and Technology, University of Calcutta, 92, A.P.C. Road, Kolkata, 700009, India. Electronic address:

Bio-composite type functional adsorbents were prepared by integrating kappa-carrageenan (KC) and copolymers of poly (N-vinylpyrrolidone-co-acrylic acid) (CP). The CP was synthesized free radically from its monomers N-vinylpyrrolidone (NVP), acrylic acid (AA) and methylene bis-acrylamide (MBA) crosslinker comonomer in the presence of KC in water. The adsorbents were characterized and used for separation of Safranine T (ST) and brilliant cresyl blue (BCB) cationic dye mixtures from water. Read More

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November 2018

ARGET-ATRP synthesis and swelling response of compositionally varied poly(methacrylic acid-co-N,N-diethylaminoethyl methacrylate) polyampholyte brushes.

Soft Matter 2018 Aug;14(30):6290-6302

Department of Chemistry, University of Tennessee Knoxville, Tennessee 37996, USA.

Modifying the composition of polyampholytes, which are comprised of charge-positive and charge-negative repeat units, directly contributes to trade-offs between charge and structure, which are externally regulated by solution pH and added salt. Here, the relative ratio of anionic and cationic comonomers is varied to tailor the stimuli-responsiveness of poly(methacrylic acid-co-N,N-diethylaminoethyl methacrylate) (P(MAA-co-DEAEMA)) brushes to changes in solution pH and an added zwitterion. These systems display a strong dependence on excess repeating units of either type and the random incorporation appears to facilitate self-neutralization of charges. Read More

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