Waterborne polyurethanes: influence of chain extender in ftir spectra profiles

Delpech, Marcia C.; Miranda, Gisele S

doi:10.2478/s13531-011-0060-3

Cited by 32 publications

(50 citation statements)

References 30 publications

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“…). The urethane and urea groups were confirmed by specific peaks at 3320 cm −1 (N–H stretching of urethane and urea groups), 1720 cm −1 (C=O stretching of urethane and urea groups), and 2940 and 2860 cm −1 (symmetric and asymmetric C–H stretching) . The specific peaks for aniline trimer were located at 1590 and 1510 cm −1 (C=C stretching of quinoid and benzenoid rings), 1300 cm −1 (C–N stretching of aromatic amine), and 860 cm −1 (C–H bending in benzenoid rings) .…”

Section: Resultsmentioning

confidence: 92%

“…The urethane and urea groups were confirmed by specific peaks at 3320 cm 21 (N-H stretching of urethane and urea groups), 1720 cm 21 (C5O stretching of urethane and urea groups), and 2940 and 2860 cm 21 (symmetric and asymmetric C-H stretching). 42 The specific peaks for aniline trimer were located at 1590 and 1510 cm 21 (C5C stretching of quinoid and benzenoid rings), 1300 cm 21 (C-N stretching of aromatic amine), and 860 cm 21 (C-H bending in benzenoid rings). 43 For CSAdoped CPU films, there was an additional peak at 1040 cm 21 attributed to the asymmetrical stretching of the sulfonyl group interacting with aniline trimer in the polyurethane backbone, which is a characteristic of the doped form of polyaniline and its derivatives.…”

Section: Cpu Characterizationmentioning

confidence: 95%

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Synthesis and characterization of conductive, biodegradable, elastomeric polyurethanes for biomedical applications

Yepez

et al. 2016

J Biomedical Materials Res

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Biodegradable conductive polymers are currently of significant interest in tissue repair and regeneration, drug delivery, and bioelectronics. However, biodegradable materials exhibiting both conductive and elastic properties have rarely been reported to date. To that end, an electrically conductive polyurethane (CPU) was synthesized from polycaprolactone diol, hexadiisocyanate, and aniline trimer and subsequently doped with (1S)-(+)-10-camphorsulfonic acid (CSA). All CPU films showed good elasticity within a 30% strain range. The electrical conductivity of the CPU films, as enhanced with increasing amounts of CSA, ranged from 2.7 ± 0.9 × 10(-10) to 4.4 ± 0.6 × 10(-7) S/cm in a dry state and 4.2 ± 0.5 × 10(-8) to 7.3 ± 1.5 × 10(-5) S/cm in a wet state. The redox peaks of a CPU1.5 film (molar ratio CSA:aniline trimer = 1.5:1) in the cyclic voltammogram confirmed the desired good electroactivity. The doped CPU film exhibited good electrical stability (87% of initial conductivity after 150 hours charge) as measured in a cell culture medium. The degradation rates of CPU films increased with increasing CSA content in both phosphate-buffered solution (PBS) and lipase/PBS solutions. After 7 days of enzymatic degradation, the conductivity of all CSA-doped CPU films had decreased to that of the undoped CPU film. Mouse 3T3 fibroblasts proliferated and spread on all CPU films. This developed biodegradable CPU with good elasticity, electrical stability, and biocompatibility may find potential applications in tissue engineering, smart drug release, and electronics. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2305-2314, 2016.

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Section: Resultsmentioning

confidence: 92%

Section: Cpu Characterizationmentioning

confidence: 95%

Synthesis and characterization of conductive, biodegradable, elastomeric polyurethanes for biomedical applications

Yepez

et al. 2016

J Biomedical Materials Res

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“…Este trabalho teve por objetivo: (1) sintetizar formulações não-poluentes à base de dispersões aquosas poliuretânicas, contendo segmentos hidrofílicos nas cadeias poliméricas e argila adicionada ao meio aquoso, e (2) testar a permeabilidade ao dióxido de carbono (CO 2 ) de membranas densas obtidas a partir do espalhamento das dispersões. [1][2][3][4][6][7][8]23,26,[31][32][33][34][35][36] . Em reator de três vias, a mistura de DMPA, PPG e EG-b-PG foi seca a 90°C, por 40 minutos, sob agitação.…”

Section: -Avaliação Das Propriedades De Barreira De Membranas Obtidasunclassified

“…O processo de pesagem foi finalizado quando foi atingida massa constante. Para cada dispersão avaliada foram realizadas triplicatas e registrado o valor médio [8,21,[33][34][35][36] . A análise viscosimétrica das dispersões foi realizada em um viscosímetro Brookfield digital usando rotor SCA-18, a 25°C, para determinação da viscosidade aparente da dispersão e o perfil de escoamento em função da taxa de cisalhamento aplicada.…”

Section: Métodosunclassified

Avaliação das Propriedades de Barreira de Membranas Obtidas a partir de Dispersões Aquosas à Base de Poliuretanos e Argila

Barboza¹,

Delpech²,

Garcia³

et al. 2014

Polímeros

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Resumo: Formulações de aplicação não-poluente à base de poliuretanos em dispersão aquosa (WPUs), com adição de argila montmorilonita hidrofílica (CWPUs), foram sintetizadas. A permeabilidade ao dióxido de carbono (CO 2 ) de membranas densas obtidas a partir do espalhamento das dispersões foi avaliada. Os reagentes empregados na síntese dos materiais foram: poli(glicol proplilênico) (PPG), copolímero em bloco à base de segmentos de poli(glicol etilênico) e poli(glicol propilênico) (EG-b-PG), ácido dimetilolpropiônico (DMPA), diisocianato de isoforona (IPDI) e etilenodiamina (EDA), como extensor de cadeia, levando à formação de ligações de ureia. Diferentes formulações foram obtidas variando-se a proporção de segmentos à base de poli(glicol etilênico) (PEG) e o teor de argila (0,5 e 1 %). As dispersões foram avaliadas em termos de teor de sólidos e viscosidade aparente. As membranas foram caracterizadas por espectrometria na região do infravermelho (FTIR) e permeabilidade ao dióxido de carbono (CO 2 ). A influência nas propriedades de barreira, conferida pela presença da argila e do copolímero em bloco, foi verificada por ensaios de permeabilidade. A permeabilidade ao CO 2 aumentou com o aumento no teor segmentos de PEG e diminuiu com a inserção da argila, uma vez que esta é impermeável a gases, formando caminhos preferenciais na matriz polimérica que retardam a difusão das moléculas de gás. Palavras-chave: Poliuretanos, dispersões aquosas, argila, montmorilonita, membranas, permeabilidade a gases, propriedades de barreira. Evaluation of Carbon Dioxide Gas Barrier Properties of Membranes Obtained from Aqueous Dispersions Based on Polyurethane and ClayAbstract: Non-polluting aqueous polyurethane-based dispersions were synthesized in the presence and absence of montmorillonite hydrophilic clay (WPUs and CWPUs, respectively). The permeability of carbon dioxide (CO 2 ) through dense membranes obtained from the dispersions was evaluated. The reagents used in the synthesis of the materials were: poly(propylene glycol) (PPG), block copolymer of poly(ethylene glycol) and poly(propylene glycol) (EG-b-PG), dimethylolpropionic acid (DMPA), isophorone diisocyanate (IPDI) and ethylene diamine (EDA) as chain extender, leading to the formation of urea linkages. The proportion of poly(ethylene glycol) (PEG) segments and clay content (0.5 and 1%) was varied in the formulations. The dispersions were evaluated in terms of solids content and apparent viscosity. The membranes were characterized by infrared spectrometry (FTIR) and permeability to carbon dioxide (CO 2 ). The influence on the gas barrier properties, imparted by different contents of PEG segments in polyurethane chains, and by the clay in the formulations was verified. The permeability of CO 2 increased with increasing amounts of PEG segments and decreased with the insertion of clay, since the latter is impermeable to gas and forms, in the polymeric matrix, tortuous pathways that retard gas diffusion.

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“…The wide range of physical properties that PU chains can adopt results from a morphological combination of hard and soft segments. The former are derived from diisocyanate and have highly polar urethane groups, and the latter are composed of polyol, which may impart elastomeric characteristics to the polymer . In polyurethane synthesis, the use of a chain extender is common, aiming for an increase in the molecular mass of the chains.…”

Section: Introductionmentioning

confidence: 99%

Waterborne poly(urethane‐urea) gas permeation membranes for CO₂/CH₄ separation

Reis

Pereira

Campos

et al. 2017

J of Applied Polymer Sci

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In this work, dense membranes from aqueous dispersions of poly(urethane‐urea) (PUU) based on poly(propylene glycol) (PPG) and a block copolymer composed of poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG), EG‐b‐PG, with 7 wt % of the former were obtained. Nonpolluting formulations were synthesized with proportions of PPG and EG‐b‐PG as 1:0, 1:1, 1:3, and 3:1 in terms of equivalent number ratios. The effect of small and gradual increases in PEG segments was evaluated for the permeability of pure CO2, CH4, and N2, at room temperature. Slight increases in PEG‐based segments in PUU promoted some remarkable properties, which led to a simultaneous increase in CO2 permeability and ideal selectivity for CH4 (300%) and N2 (380%). Infrared spectroscopy showed that the PEG portions induced hydrogen bonds between NH of urethane and ether groups in the PEG portions, which promoted ordering of the flexible segments, confirmed by X‐ray diffractometry and small‐angle X‐ray scattering. Diffractometry techniques also confirmed the absence of crystalline domains, as did dynamic mechanical analysis. The produced membranes showed performance above Robeson's 2008 upper bound and seemed to be a superior polymeric material for CO2/CH4 and CO2/N2 separation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46003.

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Waterborne polyurethanes: influence of chain extender in ftir spectra profiles

Cited by 32 publications

References 30 publications

Synthesis and characterization of conductive, biodegradable, elastomeric polyurethanes for biomedical applications

Synthesis and characterization of conductive, biodegradable, elastomeric polyurethanes for biomedical applications

Avaliação das Propriedades de Barreira de Membranas Obtidas a partir de Dispersões Aquosas à Base de Poliuretanos e Argila

Waterborne poly(urethane‐urea) gas permeation membranes for CO₂/CH₄ separation

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Waterborne polyurethanes: influence of chain extender in ftir spectra profiles

Cited by 32 publications

References 30 publications

Synthesis and characterization of conductive, biodegradable, elastomeric polyurethanes for biomedical applications

Synthesis and characterization of conductive, biodegradable, elastomeric polyurethanes for biomedical applications

Avaliação das Propriedades de Barreira de Membranas Obtidas a partir de Dispersões Aquosas à Base de Poliuretanos e Argila

Waterborne poly(urethane‐urea) gas permeation membranes for CO2/CH4 separation

Contact Info

Product

Resources

About

Waterborne poly(urethane‐urea) gas permeation membranes for CO₂/CH₄ separation