Characterization of solvent-filled polyurethane/urea-formaldehyde core-shell composites

作     者：Neuser, S. Manfredi, E. Michaud, V. 

作者机构：Ecole Polytech Fed Lausanne Inst Mat Lab Technol Composites & Polymeres LTC CH-1015 Lausanne Switzerland 

出 版 物：《MATERIALS CHEMISTRY AND PHYSICS》 (材料化学与材料物理学)

年 卷 期：2014年第143卷第3期

页      面：1018-1025页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Swiss National Science Foundation [FNRS 511482] Laboratory of Mechanical Metallurgy (LMM) at EPFL Powder Technology Laboratory (LTP) Interdisciplinary Center for Electron Microscopy (CIME) Polymer Laboratory (LP) 

主　　题：Polymers Compression and shear Mechanical testing Computer modelling and simulation 

摘      要：Encapsulation of liquid phases is a crucial step in many self-healing material systems where a healing agent has to be protected during processing and then released during a damage event. In this work, the mechanical properties of polyurethane (PU) reinforced urea-formaldehyde (UF) shells are characterized. It was found that shell thickness is both a function of PU content in the core phase and of the microcapsule diameter. Furthermore, a saturation thickness was found for high PU contents or high capsule diameters and this phenomenon had direct implications on the bursting force under compression of single microcapsules. With help of an analytical model, the Young s modulus of the hybrid PU/UF was determined and in general, PU-reinforced shells had a lower modulus but higher ductility in terms of elongation at break, leading to more resistant microcapsules overall. (C) 2013 Elsevier B.V. All rights reserved.