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Journal articles
Design of a Series of Preceramic B -Tri(methylamino)borazine-Based Polymers as Fiber Precursors: Shear Rheology Investigations
Abstract : Oscillatory shear flow of poly[B-(methylamino)borazine] was studied for suitability as a meltspinnable material. Shear rheology experiments show that viscosity of molten poly[B-(methylamino)borazine] is temperature dependent following an Arrhenius-type equation. The high value of the flow activation energy is caused by the presence of branched chains and cross-linked portions in the polymer network which supply an intrinsic rigidity to the molecular architecture. Dynamic rheological properties of polymers were measured at their spinning temperatures as a function of the oscillatory frequency. The frequency dependence of the storage and loss moduli as well as the damping factor shows that an appropriate ratio of viscosity to elasticity, i.e., 1 <
tan δ < 2.3, is necessary to allow for extrusion while a specific range of elasticity, i.e., 104 < G′ [Pa] < 3 × 104, is required for drawing the emerging molten fibers as they solidify into fine-diameter solid filaments without loss of cohesion.
https://hal-cnrs.archives-ouvertes.fr/hal-02616108
Contributor : Samuel Bernard Connect in order to contact the contributor
Submitted on : Sunday, May 24, 2020 - 11:00:37 AM
Last modification on : Friday, January 22, 2021 - 3:54:07 PM
Contributor : Samuel Bernard Connect in order to contact the contributor
Submitted on : Sunday, May 24, 2020 - 11:00:37 AM
Last modification on : Friday, January 22, 2021 - 3:54:07 PM