Electrospinning of Polyacrylonitile/Poly(methyl methacrylate) Blend: Determination of Critical Chain Entanglement Concentration

Electrospun fibre could only be produced under a certain conditions that a chain network is developed in a given electrospinning solution. For solutions with concentration lessthan entanglement concentration, Ce, electrospinning is eventually converted to electrospraying, which yieldsspherical particulates because of capillary instability at the end of the straight jet. Furthermore, in order to succeed in obtaining uniform fibres without beads, a sufficiententanglement density existing in a given solution is an important requirement. Therefore, for a given solution determination of critical chain entanglement concentration is asignificant task prior to electrospinning. The dimensionless product of intrinsic viscosity andconcentration, [η], C is referred to as Berry number, Be. The significant of the Berry number arises from the fact that for a solution to have chain entanglements, Be> 1. In various polymer solutions, different minimum value of Berry No. was reported in which electrospun nanofiber without beadobtained. The objective of the present investigation is to obtain Berry No. and consequently Ce figures for PAN/PMMA solution experimentally and theoretically as tocompare their values [1- 2- 3].