Thermoreversible cross-linking of ethylene/propylene copolymers based on Diels–Alder chemistry: the cross-linking reaction kinetics

Interaction between poly (m-phenylene isophtalamide) (PMIA) electrospun nanofibers and commercial epoxy resin precursor during the cross-linking process was investigated, in order to use such polyaramidic nanofibers for composite materials reinforcement. Hence nanofibrous PMIA mats were produced via electrospinning technique to be used for the functional modification of the epoxy matrix composite properties. When adding such fibers to an epoxy resin precursor, it was observed a strong influence on the kinetics of its curing process. The final results, however, demonstrates that boosting the reaction condition (raising the temperature and the reaction time) the curing is pushed to completion, indicating that the cross-linking process of the resin is just delayed and not completely hampered. It will be therefore necessary to rethink the composite cure cycle when PMIA nanofibers are added to the composite material, in order to attain significant improvement of the final composite performance.

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Reaction Kinetics of Gliadin−Glutenin Cross-Linking in Model Systems and in Bread Making

Journal of Agricultural and Food Chemistry ◽

10.1021/jf801894r ◽

2008 ◽

Vol 56 (22) ◽

pp. 10660-10666 ◽

Cited By ~ 51

Author(s):

Bert Lagrain ◽

Kristof Brijs ◽

Jan A. Delcour

Keyword(s):

Reaction Kinetics ◽

Model Systems ◽

Cross Linking ◽

Bread Making ◽

Kinetics Of

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Cure Monitoring of Epoxy Resin by Simultaneous DSC/FTIR

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.905 ◽

2014 ◽

Vol 881-883 ◽

pp. 905-908

Author(s):

Li Wei Wang ◽

Gerard F. Fernando

Keyword(s):

Cross Linking ◽

Resin System ◽

Fibre Optic ◽

Cure Monitoring ◽

Epoxy Amine ◽

Fibre Optic Probe ◽

The Cross ◽

Optic Probe ◽

Conventional Dsc ◽

Kinetics Of

The cross-linking kinetics of an epoxy/amine resin system was studied using the conventional DSC and FTIR spectroscopy, respectively. Conventional DSC was modified to accommodate two fibre optic probes which could be used to monitor the spectra of epoxy/amine resin system during cure. The cross-linking kinetics for the epoxy/amine resin system obtained via the conventional DSC and FTIR and simultaneous DSC/FTIR were similar. The feasibility of using a simple bifurcated fibre optic probe to link the DSC to the FTIR spectrometer was demonstrated.

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Dilatometric Measurement of the Rate of Vulcanization of Crepe Rubber by Sulfur Monochloride

Rubber Chemistry and Technology ◽

10.5254/1.3543374 ◽

1952 ◽

Vol 25 (1) ◽

pp. 48-49

Author(s):

J. Glazer

Keyword(s):

Chemical Analysis ◽

Cross Linking ◽

Mustard Gas ◽

Dilatometric Measurement ◽

Sulfur Monochloride ◽

Dilatometric Method ◽

The Cross ◽

Kinetics Of ◽

Vulcanization Process

Abstract The cold vulcanization of rubber by sulfur monochloride is believed to consist essentially of the cross-linking of adjacent polyisoprene units by a series of sulfide bonds. Chemical analysis of the product suggests that the cross-linking process is analogous to the mustard gas reaction of ethylene with sulfur monochloride, thus: (see PDF for diagram) Nothing is known, however, about the kinetics of this vulcanization process. General considerations lead one to expect that such a reaction, involving polymer aggregation, should be accompanied by an increase in the density of the rubber; moreover, by choosing a suitably delicate technique, it should be possible to utilize such density changes for rate determinations. A dilatometric method seemed most suitable, and the experiments described here show that the vulcanization process is, indeed, accompanied by a decrease in volume of the reaction mixture, and that the reaction may be followed quantitatively using a tap dilatometer.

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Kinetics of cross-linking and de-cross-linking of EPM rubber with thermoreversible Diels-Alder chemistry

European Polymer Journal ◽

10.1016/j.eurpolymj.2017.03.020 ◽

2017 ◽

Vol 90 ◽

pp. 150-161 ◽

Cited By ~ 12

Author(s):

L.M. Polgar ◽

A. Kingma ◽

M. Roelfs ◽

M. van Essen ◽

M. van Duin ◽

...

Keyword(s):

Diels Alder ◽

Cross Linking ◽

Kinetics Of

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New insights into the cross-linking and degradation mechanism of Diels–Alder hydrogels

Journal of Materials Chemistry B ◽

10.1039/c4tb01680g ◽

2015 ◽

Vol 3 (3) ◽

pp. 449-457 ◽

Cited By ~ 30

Author(s):

Susanne Kirchhof ◽

Andrea Strasser ◽

Hans-Joachim Wittmann ◽

Viktoria Messmann ◽

Nadine Hammer ◽

...

Keyword(s):

Ring Opening ◽

Degradation Mechanism ◽

Alder Reaction ◽

Diels Alder ◽

Cross Linking ◽

Diels Alder Reaction ◽

Maleamic Acid ◽

The Cross ◽

Hydrolysis Of

Degradation of Diels–Alder hydrogels occurs by retro-Diels–Alder reaction followed by OH−-catalyzed ring-opening hydrolysis of maleimide groups to unreactive maleamic acid derivatives.

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Cationic cellulose hydrogels: kinetics of the cross-linking process and characterization as pH-/ion-sensitive drug delivery systems

Journal of Controlled Release ◽

10.1016/s0168-3659(02)00410-8 ◽

2003 ◽

Vol 86 (2-3) ◽

pp. 253-265 ◽

Cited By ~ 131

Author(s):

Rosalı́a Rodrı́guez ◽

Carmen Alvarez-Lorenzo ◽

Angel Concheiro

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Delivery Systems ◽

Cross Linking ◽

The Cross ◽

Kinetics Of

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Bio-Based Thermo-Reversible Aliphatic Polycarbonate Network

Molecules ◽

10.3390/molecules25010074 ◽

2019 ◽

Vol 25 (1) ◽

pp. 74 ◽

Cited By ~ 1

Author(s):

Pierre-Luc Durand ◽

Etienne Grau ◽

Henri Cramail

Keyword(s):

Thermal Stability ◽

Biomedical Applications ◽

Diels Alder ◽

Cross Linking ◽

Important Class ◽

Aliphatic Polycarbonate ◽

Biomedical Field ◽

The Cross ◽

Thermal Stability Of

Aliphatic polycarbonates represent an important class of materials with notable applications in the biomedical field. In this work, low Tg furan-functionalized bio-based aliphatic polycarbonates were cross-linked thanks to the Diels–Alder (DA) reaction with a bis-maleimide as the cross-linking agent. The thermo-reversible DA reaction allowed for the preparation of reversible cross-linked polycarbonate materials with tuneable properties as a function of the pendent furan content that was grafted on the polycarbonate backbone. The possibility to decrosslink the network around 70 °C could be an advantage for biomedical applications, despite the rather poor thermal stability of the furan-functionalized cross-linked polycarbonates.

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Volume growth, murein synthesis, and murein cross-linkage during the division cycle of Escherichia coli PA3092

Journal of Bacteriology ◽

10.1128/jb.152.3.1248-1254.1982 ◽

1982 ◽

Vol 152 (3) ◽

pp. 1248-1254

Author(s):

A J Olijhoek ◽

S Klencke ◽

E Pas ◽

N Nanninga ◽

U Schwarz

Keyword(s):

Escherichia Coli ◽

Sodium Dodecyl ◽

Volume Growth ◽

Diaminopimelic Acid ◽

Cross Linking ◽

Penicillin Binding Protein ◽

Whole Cells ◽

Cross Linkage ◽

The Cross ◽

Kinetics Of

Cells of Escherichia coli PA3092 were synchronized by centrifugal elutriation. The synchronously growing cells were double labeled with -3H or DL-[meso-2,6-14C]diaminopimelic acid (DAP) at different times. Cells incorporated [3H]DAP at a continuously increasing rate during their cycle, with a maximum occurring at about 30 min before division for trichloroacetic acid-precipitated cells (whole cells) and about 10 min before division for sodium dodecyl sulfate-treated cells (sacculi). This was in good agreement with the observed kinetics of volume growth under these conditions. Furazlocillin, which preferentially interacts with penicillin-binding protein 3, modified the pattern of incorporation of [3H]DAP. Electron microscopy indicated that furazlocillin did not inhibit the initiation of division but rather its completion. In addition, we measured the cross-linking of the murein inserted at different times during synchronous growth. The highest percentages were found to occur around division. At this same time, the cross-linking of old peptidoglycan was found to be decreased.

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