改性蒙脱石/石蜡相变储热微囊的制备与性能表征

采用皮克林乳液法制备以改性蒙脱石为新型壁材,石蜡为芯材的储能相变微囊。采用光学显微镜、扫描电镜(SEM)、红外光谱分析仪(FTIR)、差示扫描量热仪(DSC)和热重仪(TG)等分析技术分别对蒙脱石/石蜡微胶囊的化学结构、微观形貌、热性能等进行详细的表征与解析。结果表明:改性蒙脱石壁材对石蜡芯材有良好的保护作用。微囊的FTIR特征峰与石蜡和改性蒙脱石对应的特征峰相似。DSC测试表明,改性蒙脱石/石蜡复合相变微囊储热材料的固-固相变温度与纯石蜡相近,石蜡含量为55%~80%的相变微囊的相变焓值为110.5~147.2J/g,调整石蜡含量可调控相变微囊的储能性能。TG分析表明改性蒙脱石/石蜡微囊的热稳定性能较好。研究表明,改性蒙脱石是石蜡相变微囊良好的壁材。改性蒙脱石/石蜡微囊具有成本低、性能优异的特点,具有推广应用价值。

Preparation and Characterization of Modified Montmorillonite/Paraffin Phase Change Microcapsules for Energy Storage

The phase change microcapsules of modified montmorillonite/paraffin were prepared by Pickering emulsion method.Analytic techniques of optical microscopy,scanning electron microscopy (SEM),infrared spectroscopy (FTIR),differential scanning calorimetry (DSC) and thermogravimetry (TG) were utilized for characterizing chemical structure,morphology and thermal properties.Results show that modified montmorillonite as a new type wall material has excellent performance for protecting core material of paraffin.FTIR spectra of phase change of modified montmorillonite/paraffin microcapsules shows that their characteristic peaks match with corresponding peaks of pure paraffin and modified montmorillonite.DSC results indicate that modified montmorillonite/paraffin microcapsules have similar solid-liquid phase change temperature with pure paraffin.The phase transition enthalpy values of microcapsules with paraffin contents varying from 55 ％ to 80％ are 110.5-147.2J/g,indicating that microcapsules have excellent thermal storage performance and the phase change properties can be adjusted by changing contents of paraffin.TG results confirm that modified montmorillonite/paraffin microcapsules have outstanding thermal stability.The presented study indicates that modified montmorillonite is a suitable wall material for preparing paraffin microcapsule.Modified montmorillonite/paraffin microcapsules have advantages of low cost and high performance with a great application potential in the field of thermal storage.