A quest for revisiting analysis of polycaprolactone crystallinity

This opinion proposes the need and benefits of revisiting both theory and methods to generate critical reference data for the quantification of polymer crystallinity, outlining a case study for polycaprolactone (PCL), the most widely used biodegradable polymer in biomedical and environmental research and products. No recent studies have been published in this direction, with the trend over the past 20 years being toward advanced applications of polymers, to the detriment of fundamental study. This opinion addresses strategies for the re-evaluation of the standard melting enthalpy reference data for PCL. This enquiry is intended to challenge current acceptance of a long-held mindset and is expected to facilitate the generation of the most accurate and up-to-date information for use in the pursuit of answers to our generation’s most pressing scientific questions. Polycaprolactone (PCL) has become the most widely studied biodegradable polymer over the past 100 years. Central to this utility is its semicrystalline nature. Crystallinity is among the most important fundamental properties in materials science. Differential scanning calorimetry (DSC) is routinely used to evaluate polymer crystallinity. This requires the use of reference data for the melting enthalpy of the hypothetical entirely crystalline polymer. These data have been acquired, by necessity, using extrapolation techniques and are variably reported for PCL. The scientific community would benefit from revisiting methods to obtain objective reference values to avoid inaccuracies and compromised data sets. Here we present proposed methodologies in this direction, based on current literature, along with perspectives on the importance of this topic for the greater research community. Polycaprolactone (PCL) has become the most widely studied biodegradable polymer over the past 100 years. Central to this utility is its semicrystalline nature. Crystallinity is among the most important fundamental properties in materials science. Differential scanning calorimetry (DSC) is routinely used to evaluate polymer crystallinity. This requires the use of reference data for the melting enthalpy of the hypothetical entirely crystalline polymer. These data have been acquired, by necessity, using extrapolation techniques and are variably reported for PCL. The scientific community would benefit from revisiting methods to obtain objective reference values to avoid inaccuracies and compromised data sets. Here we present proposed methodologies in this direction, based on current literature, along with perspectives on the importance of this topic for the greater research community.