Synthesis and properties of polyurethanes based on polyolefine: 1. Rigid polyurethanes and amorphous segmented polyurethanes prepared in polar solvents under homogeneous conditions

Cuvé, Léon; Pascault, Jean‐Pierre; Boiteux, Gisèle; Seytre, Gérard

doi:10.1016/0032-3861(91)90024-d

Cited by 118 publications

(57 citation statements)

References 30 publications

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“…A T g of 167 K and a ⌬c p of 15.5 10 Ϫ2 cal/g K were obtained for both the methyl and ethyl models. The ⌬c p value is consistent with that reported in the literature for crystalline and amorphous hard urethane copolymers (typically 8 -10 10 Ϫ2 cal/g K), 29 and is very close to that of other models based on different diisocyanates, synthesized in our laboratory. 30 The experimental ⌬c p values, measured after cooling at two different cooling rate, are plotted in Figure 6, where they are compared with the theoretical values predicted either for the one-phase model (line a):…”

Section: Miscibility Of Hard and Soft Segments By ⌬C P Analysissupporting

confidence: 89%

Phase behavior and some calorimetric and physical properties of diurethanes from perfluoropolyether macromonomers

Tonelli¹,

Bassi²,

Ajroldi³

1999

J. Polym. Sci. B Polym. Phys.

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Section: Miscibility Of Hard and Soft Segments By ⌬C P Analysissupporting

confidence: 89%

Phase behavior and some calorimetric and physical properties of diurethanes from perfluoropolyether macromonomers

Tonelli¹,

Bassi²,

Ajroldi³

1999

J. Polym. Sci. B Polym. Phys.

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“…The DSC curve also shows, a glass transition at the temperature T g ss of approximately 40°C related to the soft segments. As described by Barikani and Hepburn [10] and Cuve et al [11] as mentioned by the PU manufacturer, another glass transition associated to the hard segments appears at the temperature T g HS of 95 ± 1°C. Considering the DSC curve with the values of glass cand melting temperature, the hard and soft segments content can respectively be estimated [9].…”

Section: Differential Scanning Calorimetry (Dsc)mentioning

confidence: 63%

Characterization of Polyurethane Coated Aerospace Aluminium Alloy (7075) By DSC, XRD and Adhesion Test

Venkatakrishnan¹,

Senthilvelan²,

Vijayakumar³

2017

J Appl Mech Eng

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The research is envisaging characterizing the Polyurethane (PU) coating on AA 7075 so as to predict the aircraft coating life. Differential Scanning Calorimetry (DSC) and X-ray Diffractometry have been employed to investigate the differences in thermal behavior and crystalline structure of the polyurethane (GB BOND 141). DSC can be used to examine the material from a subambient starting temperature to the glass transition event and finally through the crystalline melting region. X-ray diffraction (XRD) provides important structural information about the polyurethane in the structure of semi-crystalline polymer substance consisting of two phases, viz., amorphous and crystalline as well as their fine texture which has a strong effect on physical and mechanical properties of polyurethane. After analyzing the characteristics, the extent of coating loss is examining visually in order to evaluate the adhesion property before carrying out the peel-off test.

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“…The molecular weight, polydispersity, functionality, and branch content for these materials have been previously measured by other groups. [8,9] Data from the literature are included in Table 1. …”

Section: Methodsmentioning

confidence: 99%

“…[2,[5][6][7][8][9][10][11][12] More emphasis was placed on the latter, because of the commercial availability of butadiene polyols and problematic synthesis leading to inferior performance of the isobutylene-based systems. [10] The physical properties of the hydrogenated polybutadiene (PBD) urethanes, including mechanical performance, thermal transition temperatures, degree of phase separation, and transparency have been found to depend on a number of factors, including degree of hydrogenation [5], soft segment molecular weight [13], and synthesis conditions.…”

Section: Introductionmentioning

confidence: 99%

Transparent Barrier Urethanes Based on Polyethylene Soft Segments

Tan¹,

Napadensky²,

Sloan³

et al. 2000

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A series of polyurethane elastomers has been synthesized through copolymerization of polyethylene soft segments and methylene bis(4-phenylisocyanate) (MDI) and hydrogenated MDI (H12MDI). Polyethylene soft segments were prepared by the hydrogenation of polybutadiene polyols, either before or after copolymer synthesis. Polyols from three different suppliers were used as precursors and ranged in branch content from 15% to -90%. Flexible, transparent materials were produced. The mechanical and barrier properties of these urethanes were evaluated for comparison with the performance of traditional flexible barrier materials (e.g., butyl rubber). Solvent uptake and swelling measurements were used to evaluate barrier performance. Branch content in the soft segment was found to affect both mechanical properties and solvent resistance, with low branch content leading to superior performance. Solvent diffusion coefficients for the materials were in the 10" -cm /s range, comparable to those exhibited by flexible high barrier materials.

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Synthesis and properties of polyurethanes based on polyolefine: 1. Rigid polyurethanes and amorphous segmented polyurethanes prepared in polar solvents under homogeneous conditions

Cited by 118 publications

References 30 publications

Phase behavior and some calorimetric and physical properties of diurethanes from perfluoropolyether macromonomers

Phase behavior and some calorimetric and physical properties of diurethanes from perfluoropolyether macromonomers

Characterization of Polyurethane Coated Aerospace Aluminium Alloy (7075) By DSC, XRD and Adhesion Test

Transparent Barrier Urethanes Based on Polyethylene Soft Segments

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