Preparation of High-Heat-Resistant Silicone Hollow Particles

Abstract

Single hollow particles are used in various fields, particularly in thermal insulation materials, owing to their low thermal conductivity attributed to encapsulated air properties. “The self-assembling phase separated polymer (SaPSeP) method” is an original hollowing method that is proposed by this laboratory 25 years ago. Most hollow particles prepared by the SaPSeP method have carbon, oxygen, and hydrogen polymer shells, which lack sufficient heat resistance. In this study, hollow particles with a silicone shell, which is highly heat-resistant, are prepared using the SaPSeP method using a trimer of 3-methacryloxypropylmethyldimethoxysilane (MPDS). The MPDS trimer (3MPDS) is synthesized through the sol–gel reaction of MPDS with a basic aqueous solution. Additionally, hollow particles are prepared using a new silicone oligomer composed of MPDS and dimethoxymethylvinylsilane (DMVS). Both hollow particles prepared from 3MPDS and from a new silicone oligomer composed of MPDS and DMVS showed high heat resistance. They maintained their hollow structure even when exposed to temperatures up to 900 °C.