# Gel effect function

### Description

The function calculate the change of kinetic constants due to gel effect

### Usage

1 | ```
gel(y, pars, roM, roS, roP)
``` |

### Arguments

`y` |
vector of material and energy balance, as supplied by the function |

`pars` |
vector of chemical-physical parameters, as supplied by the function |

`roM ` |
function of monomer density (Kg/L) vs. temperature (K) |

`roS ` |
function of solvent density (Kg/L) vs. temperature (K) |

`roP ` |
function of polymer density (Kg/L) vs. temperature (K) |

### Details

The function evaluate the reduction of kinetic constant of propagation, termination, initiation when gel effect take place. Several models are implemented: diffusional, segmental and reactive. User can choose among them by menu choice

### Value

A list with the following elements:

Kt decrease of bimolecular termination constant by diffusional model

Kp decrease of propagation constant by diffusional model

Kd decrease of initiator factor efficiency by diffusional model

Kts decrease of bimolecular termination constant by segmental model

Ktrmin minimal decrease of bimolecular termination constant by segmental model

Ktrmax maximal decrease of bimolecular termination constant by segmental model

PhiMvolumetric volume fraction for Monomer

PhiS volumetric volume fraction for Solvent

PHiP volumetric volume fraction for Polymer

K3 gel point parameter

K3test gel point test parameter

MwrMolecular weight at the gel point start

Vfr Free volume at the gel point start

Mw Actual molecular weight

Vf Actual free volume

Vfcr Critical free volume

### Author(s)

Gianmarco Polotti