Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Nonlinear frontal polymerization

We now return to the base model (2,17)-(2.21) of frontal polymerization. We want to find uiuformly propagating FP waves and perform linear and nonlinear stability analyses, as we did in the case of the gasless combustion model. Before we study the model, we would like to reformulate it using the reaction front approximation. [Pg.230]

Frontal polymerization, the process of propagation of a polymerization wave, is important from both fundamental and applied viewpoints. In this chapter, we reviewed theoretical results on the base model of free-radical frontal polymerization. Based on the analogy of the gasless combustion model and using the methods developed in combustion theory, we determined uniformly propagating polymerization waves and discussed their linear and nonlinear stability. [Pg.239]

D. M. G. Comissiong, L. K. Gross, and V. A. Volpert, Nonlinear dynamics of frontal polymerization with autoacceleration. Journal of Engineering Mathematics, (2004). [Pg.240]

J. Pojman, S. Popwell, V. Volpert, and V. Yolpeki, Nonlinear dynamics in frontal polymerization, in Nonlinear Dynamics in Polymeric Systems, J. Pojman and... [Pg.243]

One of the most promising applications of nonlinear dynamics to polymer science is the phenomenon of frontal polymerization (Section III). Frontal pol)mierization is a process of converting monomer into polymer via a localized reaction zone that propagates through the monomer. There are two modes of frontal polymerization. [Pg.13]

P-67). Curing of thick composites may also be a useful application (62,63). In chapter 9, Pojman et al. review nonlinear dynamics in frontal polymerization. [Pg.14]

Thermal frontal polymerization is a mode of converting monomer into polymer via a localized exothermic reaction zone that propagates through the coupling of thermal diffusion and the Arrhenius reaction kinetics of an exothermic polymerization. We review the range of nonlinear phenomena that have been observed in frontal polymerization systems and report new results on the role of gravity in spin modes and the development of spherically-propagating fronts. [Pg.106]

Shult and Volpert performed the linear stability analysis for the same model and confirmed this result (48), Spade and Volpert studied linear stability for nonadiabatic systems (49), Gross and Volpert performed a nonlinear stability for the one-dimensional case (50), Commissiong et al. extended the nonlinear analysis to two dimensions (this volume). In the former analysis, they confirmed that, unlike in SHS (57), uniform pulsations are difficult to observe in frontal polymerization. In fact, no such one-dimensional pulsating modes have been observed. [Pg.112]

Thermal frontal polymerization exhibits the full range of nonlinear dynamics phenomena, including those driven by hydrodynamics as well as driven by intrinsic feedbacks in the chemistry. Features unique to polymerization kinetics and properties allow the study of convection in fronts and novel spin modes. [Pg.117]

Frontal polymerization discovered in 1972 (5) could be realized in free-radical polymerization because of its nonlinear behavior. If the top of a mixture of monomer and initiator in a tube is attached to an external heat source, die initiators are locally decomposed to generate radicals. The polymerization locally initiated is autoaccelerated by the c(xnbinatithermal autocatalysis exclusively at the top of the reaction systmn. An interface between reacted and unreacted regions, called propagating front, is thus formed. Pojman et al. extensively studied the dynamics of frontal polymerization (d-P) and its applicatim in matoials syndiesis (I -I3). [Pg.136]

A free boundary model is ui d to describe frontal polymerization. Weakly nonlinear analysis is applied to investigate pulsating instabilities in two dimensions, llie analysis produces a pair of Landau equations, which describe the evolution of the linearly unstable modes. Onset and stability of spinning and standing modes is described. [Pg.147]

Nonlinear phenomena in any system require some type of feedback. The most obvious source of feedback in polymerization reactions is thermal autocatalysis, often called thermal runaway in the engineering literature. The heat released by the reaction increases the rate of reaction, which increases the rate of heat release, and so on. This phenomenon can occur in almost any reaction and will be important when we consider thermal frontal polymerization. [Pg.232]

Motivation for Studying Nonlinear Dynamics with Frontal Polymerization 51... [Pg.51]

Gross, L.K. and Volpert, VA. (2003) Weakly nonlinear stability analysis of frontal polymerization. Stud. Appl. Math., 110, 351-376. [Pg.67]

Asakura, K., Nihei, E., Harasawa, H., Ikumo, A., and Osanai, S. (2004) Spontaneous frontal polymerization propagating front spontaneously generated by locally autoaccelerated fee-radical polymerization. Nonlinear Dyn. Polym. Syst., 869, 135-146. [Pg.90]


See other pages where Nonlinear frontal polymerization is mentioned: [Pg.236]    [Pg.341]    [Pg.106]    [Pg.135]    [Pg.147]    [Pg.245]    [Pg.278]   
See also in sourсe #XX -- [ Pg.51 ]




SEARCH



Frontal

Frontal polymerization

Motivation for Studying Nonlinear Dynamics with Frontal Polymerization

Nonlinear polymerization

© 2024 chempedia.info