High thermal storage polyurethane composite embedded with microencapsulated phase change materials and analysis of its unsteady heat transfer

Abstract

Phase-change insulation materials can effectively extend the holding time of submarine oil and gas pipelines. Shape-stable phase-change composites have good application prospects owing to their chemical stability and leakage resistance. In this study, a microencapsulated phase-change material (MPCM)-embedded polyurethane (PU) composite (PU-MPCM) was prepared as an insulation material for subsea pipelines. The unsteady heat transfer process of the PU-MPCM composite was simulated using COMSOL Multiphysics, and an insulation experiment was conducted on this composite. PU-MPCM exhibited a high thermal storage performance and favorable shape stability. The relative effective enthalpy coefficients of PU-MPCM composites with different MPCM contents were greater than 80%. The maximum MPCM content in the PU-MPCM composite was 24 wt% (PU-MPCM24). The melting enthalpy of PU-MPCM24 reached 35.95 J/g, and its effective thermal conductivity was as low as 0.16 W/(m•K). The holding time of PU-MPCM24 could be increased by 229.79% compared with that of pure PU. The PU-MPCM composite exhibited good mechanical properties and low water absorption, making it suitable for underwater environments. Owing to its low-cost preparation process and excellent thermal properties, PU-MPCM24 can be considered a potential insulation material for practical applications in subsea pipelines.