Chemorheological model

Extensive work in the literature has focussed on the determination of the cure effects on the chemoviscosity of thermosetting resin, and a summary of the effects of cure on various chemorheological models is given in Table 4.1. 

Table 4.3. Chemorheological models for the effect of shear rate ...

Chapters 3 and 4 presented chemical, physical and chemorheological techniques useful for characterizing various reactive polymer systems. This chapter will now focus on a review of chemorheological analyses for a variety of polymer systems, including detailed experimental findings and chemorheological modeling. 

Chemorheological models for neat (unfilled) curing systems can be grouped into the following categories ... 

Malkin and Kulichikin (1991) initially reviewed the rheokinetics of cured polymers and highlighted the first empirical chemorheological models. They showed that for a simple homogeneous reaction with no diffusion limitations or gel effects for reacting epoxy-resin systems the chemoviscosity could be described by... 

Macosko (1985) describes the importance of models that combine chemical kinetics, branching theory and composition and processing conditions (temperature, shear rates) in chemorheological models for structure-property relations. 

Kuroki et al (1999) examined the chemorheology of an epoxy resin with 90 wt.% silica. Gelation was predicted by independence of tan, power-law behaviour in dynamic moduli and GPC. A modified power-law-Arrhenius chemorheology model fitted the data well. 

Reactive-extrusion and elastomer/rubber-processing systems are intimately linked with their processing (e.g. reactive extrusion), so chemorheological models for these systems will be discussed alongside their process modelling in Chapter 6. 

Chemorheological models are an integral part of process modelling of reactive polymer systems, as shown below. Integral parts of a flow-modelling procedure are the following ... 

Mathematical solver process, such as finite-difference or finite-element analyses. When the kinetic and chemorheological models are input into this procedure, process modelling is enabled. Chapter 6, in which process modelling of various reactive systems is investigated, will examine this further in more detail. 

Industrial technologies, chemorheological modelling and process modeiiing for processing reactive poiymers... 

Zhu et al. (2005) Polymerization of caprolactone Review of one- and three-dimensional process models coupled with kinetics and chemorheological models Predictions of mixing mechanism, heat generation and heat loss are better from three-dimensional model... 

Cure kinetics and chemorheological models are key for characterizing and modelling RTM processes. For example, Lobo (1992) utilized the following kinetic and chemorheological models for a vinyl ester RTM resin. The kinetic model is given by... 

Process modelling of RTM polyesters was examined by Kenny et al. (1990), who identified the following (auto-catalytic) cure kinetic and (empirical Castro-Macosko (Castro and Macosko 1982) model, as highlighted in (Equation 5.8)) chemorheological models for use in their process simulation ... 

Manzione et al. (1988) presented an empirical model for transfer moulding of filled epoxyresin systems for integrated-circuit encapsulation. The following chemorheological model (combining temperature, shear and cure effects) was used to aid flow-balancing calculations ... 

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