An Experimental Approach of Introducing Polymer Crystallization to Students using Diblock Copolymer Thin Films
Description
Polymer crystallization lessons within graduate and postgraduate units have mostly been taught theoretically. This article provides a systematic method of introducing polymer crystallization laboratory lesson to students by blending theoretical knowledge with practical approaches. Students can visualize and measure crystal growth rates as well as distinct crystal lamellae thicknesses. The measured growth rates and the crystal lamellar thicknesses can be linked directly to the theoretical models found in the literature. The activities presented will enable students better engage in their learning journey and so write meaningful reports and enhance subject learning outcomes of the lesson by strengthening their understanding as to why crystal growth rate varies with different undercooling values. Symmetric low and high molecular weight polystyrene-block-polyethylene oxide (PS-b-PEO) diblock copolymer thin films were used. PEO is the crystalline chain and PS, the amorous chain. While optical microscopy promoted the visualisation of the crystal growth front, atomic-force microscopy assisted in the determination of the detailed surface structures.