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You searched for: Publication Year 2019 Remove constraint Publication Year: 2019 Subject differential scanning calorimetry Remove constraint Subject: differential scanning calorimetry Subject composite polymers Remove constraint Subject: composite polymers
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1. Ring opening polymerization and copolymerization of L‐lactide and ɛ‐caprolactone by bis‐ligated magnesium complexes

Author:
Slattery, Reile M.; Stahl, Amanda E.; Brereton, Kelsey R.; Rheingold, Arnold L.; Green, David B.; Fritsch, Joseph M.
Source:
Journal of polymer science 2019 v.57 no.1 pp. 48-59
ISSN:
0887-624X
Subject:
composite polymers; copolymerization; differential scanning calorimetry; gel chromatography; geometry; ligands; magnesium; molecular weight; nuclear magnetic resonance spectroscopy
Abstract:
... Seven magnesium complexes (1–7) were synthesized by reaction of new (L ³‐H–L ⁵‐H) and previously reported ketoimine pro‐ligands with dibutyl magnesium and were isolated in 59–70% yields. Complexes 1–7 were characterized fully and consisted of bis‐ligated homoleptic ketoiminates coordinated in distorted octahedral geometry around the magnesium centers. The complexes were investigated for their abil ...
DOI:
10.1002/pola.29280

2. Charge Transport in Imidazolium-Based Homo- and Triblock Poly(ionic liquid)s

Author:
Mapesa, Emmanuel U.; Chen, Mingtao; Heres, Maximilian F.; Harris, Matthew A.; Kinsey, Thomas; Wang, Yangyang; Long, Timothy E.; Lokitz, Bradley S.; Sangoro, Joshua R.
Source:
Macromolecules 2019 v.52 no.2 pp. 620-628
ISSN:
1520-5835
Subject:
ambient temperature; bromides; composite polymers; dielectric spectroscopy; differential scanning calorimetry; glass transition temperature; ionic liquids; polystyrenes
Abstract:
... Ion dynamics in a series of imidazolium-based triblock copolymers (triblock co-PILs) are investigated using broadband dielectric spectroscopy (BDS) and differential scanning calorimetry (DSC) and compared to their homopolymer counterparts (homo-PILs). Two calorimetric glass transition temperatures (Tg) are observed corresponding to the charged poly(ionic liquid) (PIL) blocks and noncharged polysty ...
DOI:
10.1021/acs.macromol.8b02143

3. Imidazolium-Based Copoly(Ionic Liquid) Membranes for CO₂/N₂ Separation

Author:
Nellepalli, Pothanagandhi; Tomé, Liliana C.; Vijayakrishna, Kari; Marrucho, Isabel M.
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.5 pp. 2017-2026
ISSN:
1520-5045
Subject:
asymmetric membranes; carbon dioxide; chemical structure; composite polymers; copolymerization; differential scanning calorimetry; environmental policy; ionic liquids; nitrogen; nuclear magnetic resonance spectroscopy; permeability; process design; salts; thermogravimetry
Abstract:
... The development of efficient carbon dioxide capture and separation technologies is at the forefront of the priorities in climate change policies. Poly(ionic liquid)s (PILs) have been emerging as extremely promising materials for the fabrication of membranes for CO₂ separation. This work is a step forward to evaluate the effect of the PIL-based copolymers chemical structures in the preparation and ...
DOI:
10.1021/acs.iecr.8b05093

4. Sustainable Framework of Chitosan–Benzoxazine with Mutual Benefits: Low Curing Temperature and Improved Thermal and Mechanical Properties

Author:
Monisha, Monisha; Yadav, Nisha; Lochab, Bimlesh
Source:
ACS sustainable chemistry & engineering 2019 v.7 no.4 pp. 4473-4485
ISSN:
2168-0485
Subject:
Fourier transform infrared spectroscopy; chitosan; composite polymers; differential scanning calorimetry; mechanical properties; nuclear magnetic resonance spectroscopy; polymerization; schiff bases; synergism; temperature; thermal stability; thermogravimetry; vanillin
Abstract:
... Polybenzoxazines (PBzs) are emerging as a highly promising and superior class of thermoset polymers for a variety of applications. However, it remains a significant challenge to substantially lower the ring-opening polymerization (ROP) temperature with an ease in processability. On the other hand, biomacromolecule chitosan (CS) is explored extensively, but its practical applications have been prec ...
DOI:
10.1021/acssuschemeng.8b06515

5. Bimodal Crystallization Kinetics of PBT/PTHF Segmented Block Copolymers: Impact of the Chain Rigidity

Author:
de Almeida, André; Nébouy, Matthias; Baeza, Guilhem P.
Source:
Macromolecules 2019 v.52 no.3 pp. 1227-1240
ISSN:
1520-5835
Subject:
composite polymers; crystallization; differential scanning calorimetry; gelation; models; prediction; rheology; topology
Abstract:
... By combining linear rheology and differential scanning calorimetry experiments performed under isothermal and nonisothermal conditions, we clarify the mechanisms of crystallization occurring in three industrially relevant PBT/PTHF segmented block copolymers. After a careful and systematic analysis of the crystallization kinetics based on “classic” Avrami-like models (1 < n < 2), we reveal (and qua ...
DOI:
10.1021/acs.macromol.8b01689

6. Copolymerization of Cyclic Phosphonate and Lactide: Synthetic Strategies toward Control of Amphiphilic Microstructure

Author:
Beament, James; Wolf, Thomas; Markwart, Jens C.; Wurm, Frederik R.; Jones, Matthew D.; Buchard, Antoine
Source:
Macromolecules 2019 v.52 no.3 pp. 1220-1226
ISSN:
1520-5835
Subject:
aluminum; composite polymers; copolymerization; differential scanning calorimetry; microstructure; nuclear magnetic resonance spectroscopy; phosphonates; phosphorus; solubility; stable isotopes; temperature; thermal properties; thermogravimetry
Abstract:
... Controlling the microstructure of polymers through chemical reactivity is key to control the material properties of synthetic polymers. Herein we investigate the ring-opening copolymerization of a mixture of lactide and 2-ethyl-2-oxo-1,3,2-dioxaphospholane, promoted by an aluminum pyrrolidine monophenolate complex or 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). This monomer mixture provides fast acce ...
DOI:
10.1021/acs.macromol.8b02385

7. Electroactive phase nucleation and isothermal crystallization kinetics in ionic liquid-functionalized ZnS nanoparticle-ingrained P(VDF-HFP) copolymer nanocomposites

Author:
Dutta, Bula; Deb, Debalina; Bhattacharya, Subhratanu
Source:
Journal of materials science 2019 v.54 no.4 pp. 2990-3008
ISSN:
0022-2461
Subject:
Fourier transform infrared spectroscopy; Gibbs free energy; X-ray diffraction; composite polymers; crystal structure; crystallites; crystallization; differential scanning calorimetry; hydrophobicity; melting; mixing; nanocomposites; nanoparticles; temperature; transmission electron microscopy; zinc sulfide
Abstract:
... Poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP))-based copolymer nanocomposites are prepared by blending with hydrophobic ionic liquid-functionalized ZnS nanoparticles. Different characterization techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and differential scanning calorimetry (DSC) are employed to investigate the eff ...
DOI:
10.1007/s10853-018-3027-4

8. New organic-inorganic hybrids as multifunctional additives to improve ethylene-norbornene (EN) composite stability

Author:
Marzec, Anna; Szadkowski, Bolesław; Rogowski, Jacek; Maniukiewicz, Waldemar; Zaborski, Marian
Source:
Polymer degradation and stability 2019 v.160 pp. 110-119
ISSN:
0141-3910
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; additives; azo dyes; composite polymers; crystal structure; differential scanning calorimetry; mass spectrometry; mechanical testing; pigments; scanning electron microscopy; tensile strength; thermal stability; thermogravimetry; ultraviolet radiation
Abstract:
... In this study, new multifunctional organic-inorganic pigments were synthesized by the complexation of carboxlic azo dyes (D1, D2) with aluminum-magnesium hydroxycarbonate (LH) and were applied as colorants in ethylene-norbornene copolymer (EN). The structures of the hybrid pigments were analyzed by X-ray diffraction (XRD), secondary ion mass spectrometry (TOF-SIMS), thermogravimetric analysis (TGA ...
DOI:
10.1016/j.polymdegradstab.2018.12.012

9. Sustainable Bioconversion of Cassava Waste to Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) by Halogeometricum borinquense Strain E3

Author:
Salgaonkar, Bhakti B.; Mani, Kabilan; Bragança, Judith M.
Source:
Journal of polymers and the environment 2019 v.27 no.2 pp. 299-308
ISSN:
1566-2543
Subject:
Fourier transform infrared spectroscopy; agricultural wastes; biotransformation; carbon; carotenoids; cassava; composite polymers; differential scanning calorimetry; effluents; glucose; hydrolysates; nuclear magnetic resonance spectroscopy; polyhydroxyalkanoates; sago; starch; sugarcane bagasse; ultraviolet-visible spectroscopy; India
Abstract:
... The production of sago starch from cassava at an industrial scale in Salem, Tamil Nadu, India results in discharge of starch/carbon-rich fibrous waste and effluents, contributing to a major environmental problem. The present study aimed at exploring the potential of an extremely halophilic archaeon, Halogeometricum borinquense strain E3 to utilize starch and cassava waste (CW) as carbon substrate ...
DOI:
10.1007/s10924-018-1346-9

10. Synthesis and characterization of two new biobased poly(pentylene 2,5-furandicarboxylate-co-caprolactone) and poly(hexamethylene 2,5-furandicarboxylate-co-caprolactone) copolyesters with enhanced enzymatic hydrolysis properties

Author:
Kasmi, Nejib; Wahbi, Mohamed; Papadopoulos, Lazaros; Terzopoulou, Zoi; Guigo, Nathanaël; Sbirrazzuoli, Nicolas; Papageorgiou, George Z.; Bikiaris, Dimitrios N.
Source:
Polymer degradation and stability 2019 v.160 pp. 242-263
ISSN:
0141-3910
Subject:
Fourier transform infrared spectroscopy; carbon; catalysts; chemical structure; composite polymers; copolymerization; differential scanning calorimetry; enzymatic hydrolysis; gas chromatography-mass spectrometry; glass transition temperature; melting point; nuclear magnetic resonance spectroscopy; polyesters; pyrolysis gas chromatography; stable isotopes; thermal stability; thermogravimetry
Abstract:
... Herein, two fully renewable copolyester series, namely poly(pentylene 2,5-furandicarboxylate-co-caprolactone) (PPeCFs) and poly(hexamethylene 2,5-furandicarboxylate-co-caprolactone) (PHeCFs) were successfully synthesized with combining ε-caprolactone (CL) with poly(pentylene 2,5-furandicarboxylate) (PPeF) and poly(hexamethylene 2,5-furan dicarboxylate) (PHeF) with different molar ratios. These mat ...
DOI:
10.1016/j.polymdegradstab.2019.01.004

11. Influence of Grafting Density and Distribution on Material Properties Using Well-Defined Alkyl Functional Poly(Styrene-co-Maleic Anhydride) Architectures Synthesized by RAFT

Author:
Moriceau, Guillaume; Tanaka, Joji; Lester, Daniel; Pappas, George S.; Cook, Alexander B.; O’Hora, Paul; Winn, Joby; Smith, Timothy; Perrier, Sébastien
Source:
Macromolecules 2019 v.52 no.4 pp. 1469-1478
ISSN:
1520-5835
Subject:
alcohols; composite polymers; crystallization; differential scanning calorimetry; gel chromatography; maleic anhydrides; molecular weight; polymerization; temperature; thermal properties; thermogravimetry; viscosity
Abstract:
... Poly(styrene-co-maleic anhydride) copolymers (PSMA) with controlled number and distribution of maleic anhydride (MAnh) units were synthesized by reversible addition–fragmentation chain transfer polymerization using chain-transfer agents (CTA) suitable for industrial scale processes. Linear- and star-shaped alternating PSMA polymers were prepared in a single-step synthesis, while a one-pot sequenti ...
DOI:
10.1021/acs.macromol.8b02231

12. Pronounced Surface Effects on the Curie Transition Temperature in Nanoconfined P(VDF-TrFE) Crystals

Author:
Meereboer, Niels L.; Terzić, Ivan; Mellema, Harm Hendrik; Portale, Giuseppe; Loos, Katja
Source:
Macromolecules 2019 v.52 no.4 pp. 1567-1576
ISSN:
1520-5835
Subject:
composite polymers; crystals; differential scanning calorimetry; phase transition; polystyrenes; temperature; wide-angle X-ray scattering
Abstract:
... Changes in the Curie transition temperature of nanoconfined poly(vinylidene fluoride–trifluoroethylene) P(VDF-TrFE) copolymers can have a severe impact on the electroactive behavior and the application range of these materials. Therefore, the origin of the change in the Curie transition temperature requires a profound understanding. In this work, block copolymer self-assembly into a spherical morp ...
DOI:
10.1021/acs.macromol.8b02382
PubMed:
31231141
PubMed Central:
PMC6581470

13. Tapered Multiblock Copolymers Based on Isoprene and 4-Methylstyrene: Influence of the Tapered Interface on the Self-Assembly and Thermomechanical Properties

Author:
Galanos, Eftyxis; Grune, Eduard; Wahlen, Christian; Müller, Axel H. E.; Appold, Michael; Gallei, Markus; Frey, Holger; Floudas, George
Source:
Macromolecules 2019 v.52 no.4 pp. 1577-1588
ISSN:
1520-5835
Subject:
composite polymers; copolymerization; cyclohexanes; differential scanning calorimetry; glass; isoprene; mechanical properties; moieties; molecular weight; rheology; small-angle X-ray scattering; styrene; temperature
Abstract:
... The synthesis of tapered multiblock copolymers by statistical living anionic copolymerization of a mixture of isoprene (I) and 4-methylstyrene (4MS) in cyclohexane is based on vastly different reactivity ratios of I and 4MS (rI = 25.4 and r₄MS = 0.007). A library of tapered multiblock copolymers was prepared with different molecular weights (approximate molecular weights of 80, 240, and 400 kg/mol ...
DOI:
10.1021/acs.macromol.8b02669

14. Nonmigratory Poly(vinyl chloride)-block-polycaprolactone Plasticizers and Compatibilizers Prepared by Sequential RAFT and Ring-Opening Polymerization (RAFT-T̵-ROP)

Author:
Sun, Zhonghe; Choi, Bonnie; Feng, Anchao; Moad, Graeme; Thang, San H.
Source:
Macromolecules 2019 v.52 no.4 pp. 1746-1756
ISSN:
1520-5835
Subject:
composite polymers; differential scanning calorimetry; light microscopy; mixing; organochlorine compounds; phthalates; plasticizers; poly(vinyl chloride); polymerization; vinyl acetate; vinyl chloride; wide-angle X-ray scattering
Abstract:
... Well-defined nonmigrating polymeric plasticizers, poly(vinyl chloride)-block-polycaprolactone (PVC-b-PCL), were synthesized by sequential reversible addition–fragmentation chain transfer (RAFT) polymerization and ring-opening polymerization (ROP) with 2-hydroxyethyl 2-(ethoxycarbonothioylthio)propanoate (HECP) as RAFT agent and incipient initiator for ROP of ε-caprolactone (CL, oxepan-2-one). Kine ...
DOI:
10.1021/acs.macromol.8b02146

15. Poly(ethylene glycol) with Multiple Aldehyde Functionalities Opens up a Rich and Versatile Post-Polymerization Chemistry

Author:
Blankenburg, Jan; Maciol, Kamil; Hahn, Christoph; Frey, Holger
Source:
Macromolecules 2019 v.52 no.4 pp. 1785-1793
ISSN:
1520-5835
Subject:
composite polymers; copolymerization; differential scanning calorimetry; ethylene oxide; gel chromatography; hydrazones; matrix-assisted laser desorption-ionization mass spectrometry; molecular weight; nuclear magnetic resonance spectroscopy; polyethylene glycol; thermal properties
Abstract:
... Two novel epoxide monomers 3,3-dimethoxy-propanyl glycidyl ether (DMPGE) and 3,3-dimethoxy-2,2-dimethylpropanyl glycidyl ether (DDPGE) were developed for the introduction of multiple aldehyde functionalities into the poly(ethylene glycol) (PEG) backbone. The acetal protecting group for the aldehyde functionality is stable against the harsh, basic conditions of the anionic ring-opening polymerizati ...
DOI:
10.1021/acs.macromol.8b02639

16. Form-stable and thermally induced flexible composite phase change material for thermal energy storage and thermal management applications

Author:
Wu, Weixiong; Wu, Wei; Wang, Shuangfeng
Source:
Applied energy 2019 v.236 pp. 10-21
ISSN:
0306-2619
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; absorption; additives; composite polymers; convection; deformation; differential scanning calorimetry; graphene; hardness; latent heat; melting point; olefin; phase transition; scanning electron microscopy; temperature; thermal conductivity; thermal energy; thermal stability; thermogravimetry
Abstract:
... High latent heat of phase change materials (PCM) has made them as one of the most potential materials in many advanced applications. However, application of PCM is limited by the issues of low thermal conductivity, leakage and strong rigidity. In this work, a novel form-stable and thermally induced flexible composite PCM inspired by shape memory polymers was successfully prepared. Here, paraffin ( ...
DOI:
10.1016/j.apenergy.2018.11.071

17. Structure and thermal properties of various alcoholysis products from waste poly(ethylene terephthalate)

Author:
Zhou, Xing; Wang, Chenxi; Fang, Changqing; Yu, Ruien; Li, Yaguang; Lei, Wanqing
Source:
Waste management 2019 v.85 pp. 164-174
ISSN:
0956-053X
Subject:
Fourier transform infrared spectroscopy; alcoholysis; bottles; catalysts; chemical industry; composite polymers; differential scanning calorimetry; food packaging; matrix-assisted laser desorption-ionization mass spectrometry; nuclear magnetic resonance spectroscopy; polyethylene terephthalates; propylene glycol; recycling; temperature; thermal properties; thermogravimetry; wastes
Abstract:
... Waste polyethylene terephthalate (PET) has been a core member in plastic polluters due to the great amount consumption in food packaging, soft-drink bottles, fibers and films. It is essential to recycle waste PET and alcoholysis is a significant way to accomplish chemical recycling. In this work, three kinds of dihydric alcohols, including neopentyl glycol (NPG), dipropylene glycol (DPG) and poly( ...
DOI:
10.1016/j.wasman.2018.12.032

18. Poly(vinylidene fluoride)/Polymethylene-Based Block Copolymers and Terpolymers

Author:
Zapsas, George; Patil, Yogesh; Bilalis, Panayiotis; Gnanou, Yves; Hadjichristidis, Nikos
Source:
Macromolecules 2019 v.52 no.5 pp. 1976-1984
ISSN:
1520-5835
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; atomic force microscopy; composite polymers; crystallization; differential scanning calorimetry; gel chromatography; iodine; light scattering; nuclear magnetic resonance spectroscopy; polymerization; polystyrenes; solvents; thermoplastics
Abstract:
... Dual crystalline diblock copolymers consisting of polymethylene (PM) and poly(vinylidene fluoride) (PVDF) blocks as well as triblock terpolymers with polystyrene (PS) as middle block were synthesized. For the synthesis, two/three different polymerization methods such as polyhomologation, atom transfer radical polymerization (ATRP), and iodine transfer polymerization (ITP) along with chain-end post ...
DOI:
10.1021/acs.macromol.8b02663

19. Combination of Ethylene, 1,3-Butadiene, and Carbon Dioxide into Ester-Functionalized Polyethylenes via Palladium-Catalyzed Coupling and Insertion Polymerization

Author:
Zhang, Yixin; Xia, Jian; Song, Jiawen; Zhang, Jianfu; Ni, Xufeng; Jian, Zhongbao
Source:
Macromolecules 2019 v.52 no.6 pp. 2504-2512
ISSN:
1520-5835
Subject:
carbon dioxide; catalytic activity; chemoselectivity; composite polymers; copolymerization; diastereomers; differential scanning calorimetry; esterification; ethylene; feedstocks; industry; microstructure; nuclear magnetic resonance spectroscopy; palladium; polyethylenes; regioselectivity; stereoselectivity
Abstract:
... The combination of ethylene (E), 1,3-butadiene (BD), and carbon dioxide (CO₂), three extensively utilized feedstocks, into a polymer via the copolymerization pathway is of great interest in both academia and industry. However, copolymerization for even two of them (E/BD, E/CO₂, BD/CO₂) is highly challenging; thus, copolymerization for three of them (E/BD/CO₂) together is more elusive and remains u ...
DOI:
10.1021/acs.macromol.9b00195

20. Flexible photochromic cellulose triacetate based bionanocomposites modified with sol-gel synthesized V2O5 nanoparticles

Author:
Gomez-Hermoso-de-Mendoza, Joseba; Barud, Hernane S.; Gutierrez, Junkal; Tercjak, Agnieszka
Source:
Carbohydrate polymers 2019 v.208 pp. 50-58
ISSN:
0144-8617
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; atomic force microscopy; biocompatibility; cellulose; composite polymers; differential scanning calorimetry; hydrogen bonding; irradiation; nanocomposites; nanoparticles; thermogravimetry; ultraviolet radiation; ultraviolet-visible spectroscopy
Abstract:
... Transparent and flexible bionanocomposites with photochromic properties based on cellulose triacetate (CTA) and sol-gel synthesized V2O5 nanoparticles were prepared. Poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (EPE) triblock copolymer was added to achieve nanostructured materials and simultaneously control the dispersion of synthesized V2O5 nanoparticles. Investigated bionanocomposites ...
DOI:
10.1016/j.carbpol.2018.12.045