Crystallization behaviour analysis of norbornene based semicrystalline cyclic olefin copolymer (c-COC) for Point-of-care (PoC) device manufacturing

Cyclic Olefin Copolymer (COC) based on norbornene and ethylene is known to be one of the most promising materials for the fabrication of low-cost miniaturized Point-of-care (PoC) devices. Although semicrystalline materials are chemically more resistant and less brittle than amorphous ones, little literature has been reported on the unique semicrystalline COC (c-COC) grade. In this work, a thorough analysis of the crystallization behaviour of a semicrystalline COC (c-COC) is reported for the first time to better understand the relationship between the crystallization and injection moulding processing parameters of the material for the mass manufacturing of PoC devices. The complete thermomechanical characterization carried out by dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) for the analysis of the crystallization behaviour suggested that even though a bimodal melting was detected by calorimetry, a unique crystalline structure was detected by X-ray scattering patterns confirming that the crystalline structure generated during the injection moulding of PoC parts is always the same regardless of processing conditions. In non-isothermal crystallization kinetics, the Ozawa model failed describing the crystallization behaviour of the c- COC whereas the combined Avrami-Ozawa and Avrami models successfully described the crystallization behaviour showing an excellent fitting to experimental values and suggesting a three-dimensional growth of nucleus for non-isothermal crystallization.

Automated summary

This study provides a detailed analysis of the crystallization behavior of semi-crystalline COC material. The results show that the crystalline structure generated during the injection molding of PoC device parts remains the same regardless of processing conditions. The study on the non-isothermal crystallization kinetics suggests that the Avrami-Ozawa and Avrami models are effective in describing the crystallization behavior of the material.