Viscoelasticity of polydimethylsiloxane at the sol-gel threshold: structural effects

• Autorzy: Gasparoux J. , Tixier T. , Tordjeman P.
• Konferencja: Third International Conference on Engineering Rheology, ICER 2005
• Języki publikacji: EN

Abstrakty

EN

Six model polydimethylsiloxane (PDMS) networks were obtained by hydrosilation of a difunctional vinyl-terminated PDMS prepolymer with a SiH containing crosslinker. Viscoelastic experiments were performed in order to study the influence of molecular parameters on the dynamic properties around the sol-gel threshold. Critical parameters were determined close to and above the sol-gel threshold. Our results show, in agreement with those of Lusignan et al. (1999), that the gel growth mechanism is function of the ratio N/Ne, where N and Ne are the numbers of Kuhn monomers between branch points and between entanglements, respectively. By considering the literature results, three universality classes are pointed out for polymer gelation: the sol-gel transition is governed by critical percolation for N/Ne < 1, by Diffusion Limited Cluster Aggregation for 1 < N/Ne < 2, and by mean field theory for N/Ne > 2.

Słowa kluczowe

EN

sol-gel transition; fractal dimension; Rouse dynamics

PL

lepkosprężystość; wymiar fraktalny; efekt strukturalny

• Wydawca: Oficyna Wydawnicza Uniwersytetu Zielonogórskiego
• Czasopismo: International Journal of Applied Mechanics and Engineering
• Rocznik: 2005
• Tom: Vol. 10, no spec
• Strony: 315--322
• Opis fizyczny: Bibliogr. 21 poz., tab., wykr.

Twórcy

autor

Gasparoux J.

• Laboratoire d'Analyse des Interfaces et de Nanophysique - UMR-5011 Université Montpellier 2 cc 082 - Place E. Bataillon 34095 Montpellier Cedex 5 - FRANCE

autor

Tixier T.

• Laboratoire d'Analyse des Interfaces et de Nanophysique - UMR-5011 Université Montpellier 2 cc 082 - Place E. Bataillon 34095 Montpellier Cedex 5 - FRANCE

autor

Tordjeman P.

• Laboratoire d'Analyse des Interfaces et de Nanophysique - UMR-5011 Université Montpellier 2 cc 082 - Place E. Bataillon 34095 Montpellier Cedex 5 - FRANCE

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