Polyamide capsules via soft templating with oil drops—1. Morphological studies of the capsule wall

Poly(terephthalamide) microcapsules can be reproducibly and easily prepared by interfacial polycondensation around emulsion droplets in water. Oil drops of cyclohexane/chloroform mixture stabilized with poly(vinyl alcohol) containing terephthaloylchloride serve as soft template. The interfacial polycondensation starts immediately after addition of an amine mixture (hexamethylenediamine/diethylenetriamine). Light and scanning electron microscopy prove the formation of capsules with size distribution in the range from a few up to 100 µm depending on particular composition of the reaction mixture. The morphology of the capsule wall is characterized by precipitated particles. If instead of pure organic solvents a reactive oil phase is used as template, the capsules can serve in subsequent reactions as templates for the synthesis of composite particles. In this way, styrene can be radically polymerized inside the capsule leading to composite capsules. The capsule morphology is determined by the partition of all components between all phases

The Study on Paraffin-Water Emulsion PCM with Low Supercooling Degree

Department of Building Services EngineeringRefereed conference pape

Introduction

A thermal energy storage system can be regarded as a heat exchanger device which has the heat transfer between the heat transfer fluid and the phase change materials. In this chapter, the fundamental for energy storage system, as well as the modeling method for thermal system is introduced. The most recent entransy analysis methodology is described and compared with previous energy and exergy theories, and a detailed literature review is presented on entransy dissipation theory