The effect of interface debonding behaviors on the mechanical properties of microPCMs/epoxy composites

• Published in: Polymer composites Vol. 32; no. 9; pp. 1439 - 1450
• Main Authors: Wang, Xin-Yu, Su, Jun-Feng, Wang, Sheng-Bao, Zhao, Yun-Hui
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.09.2011; Wiley
• Subjects: Applied sciences; Composites; Exact sciences and technology; Forms of application and semi-finished materials; Polymer industry, paints, wood; Technology of polymers; Particle size; Heat treatment; Microcapsule; Epoxy resin; Mechanical properties; Experimental study; Composite material; Tensile strength; Aminoplast; Young modulus; Morphology; Concentration effect; Melamine resin; PCM material; Heat transfer
• ISSN: 0272-8397; 1548-0569
• DOI: 10.1002/pc.21174

Microcapsules containing phase change materials (microPCMs) can be filled in polymeric matrix forming smart temperature‐controlling composites. The aim of this study was to investigate the relationship between the interface behaviors and the mechanical properties of methanol‐melamine‐formaldehyde shell microPCMs containing paraffin/epoxy matrix composites. The typical microPCMs with core/shell ratio of 2/1 shapely decreased their average diameter from 26.0 ± 1.5 to 13.8 ± 3.4 μm with the increasing of stirring speed from 1,000 to 3,000 r min−1. But, both the thickness and yield point of shells had a little variation. Young's modulus of composites was almost independent on the particle size of microPCMs with lower volume fractions (5%–10%). For composites with higher microPCMs loading (20%–30%), there was a slight decrease in modulus with increasing particle size. The data of tensile strength decreased obviously with the increasing of the average diameter of microcapsules for composite samples with the same particle loading. A repeated heat‐transmission treatment was applied to enhance the interface debonding. The results show that the violent thermal transmission had decreased the mechanical properties of microPCMs/epoxy composites. The scanning electron microscopy morphologies had also proved that these phenomena attributed to the interphase separation and cracks. Moreover, a semiexperiential conclusion is that the increasing of interface area of composites will at the same time give more structure defects leading to poor mechanical properties. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers