Preparation of bio-based heat storage microcapsules of cellulose acetate butyrate/ polymethylmethacrylate composite by micro-suspension polymerization

ABSTRACTBecause of environmental concerns, the utilization of bio-based, renewable resource materials has attracted great attention for a wide range of applications. In this research, green cellulose-based microcapsules containing capric acid (CA) as a bio-heat storage material were prepared. Cellulose acetate butyrate (CAB)/methacrylate polymer composite particles were produced by microsuspension iodine transfer polymerization to encapsulate CA. The influences of methacrylate polymer type and amount on microcapsule morphology, encapsulation efficiency (EE) and thermal properties were investigated. Using methyl methacrylate (MMA) monomer, the colloidal stable spherical microcapsules with smooth surfaces and core-shell morphology were obtained. Although high percentages of EE, ≥70%, were obtained at all CAB:MMA weight ratios, the latent heats of the encapsulated CA were lower than those of the original ones which may be due to the incomplete phase separation of the CAB/PMMA shell and CA core. The increase of CA content up to 60% provided stable spherical microcapsules with a maximum loading of 59% and 97% EE. After thermal cycling for 100 cycles, stable microcapsules still remained with stable thermal properties. The obtained bio-based microcapsules would be well applied for heat storage and temperature control applications.KEYWORDS: Cellulose acetate butyrateheat storage materialsmicrocapsulesuspension polymerization AcknowledgmentsThis research was supported by The Science, Research and Innovation Promotion Funding (TSRI) (Grant No. FRB650070/0168). This research block grant was managed under the Rajamangala University of Technology Thanyaburi (FR65E0602A.2). It was partially supported by the Thailand Institute of Scientific and Technological Research (TISTR), THAILAND. It is also partly supported by Reinventing University Project (RMUTT) 2022, Office of the Ministry of Higher Education, Science, Research and Innovation, Thailand Science Research and Innovation. The authors also thank RMUTT Central Lab, Institute of Research and Development, Rajamangala University of Technology Thanyaburi for facility support.Disclosure statementNo potential conflict of interest was reported by the authors.Additional informationFundingThe work was supported by the The Science, Research and Innovation Promotion Funding (TSRI) (Grant No. FRB650070/0168). This research block grant was managed under the Rajamangala University of Technology Thanyaburi (FR65E0602A.2) .Notes on contributorsChanakan Kheaw-InChanakan Kheaw-in received her bachelor's degree (2019) in chemistry from the Department of Chemistry, Faculty of Science and Technology, at Rajamangala University of Technology Thanyaburi (RMUTT), Thailand. He is currently a master student in the program of Applied Chemistry in the same department. His research interest focuses on the microencapsulation using bio-based polymer.Kanlapangha RattanasaikaewKanlapangha Rattanasaikaew received her bachelor's degree (2017) in the field of chemistry and master's degree (2020) in the field of applied chemistry from the Department of Chemistry, Faculty of Science and Technology, at Rajamangala University of Technology Thanyaburi (RMUTT), Thailand. She is currently a research assistant at Polymer Colloids Lab, Department of Chemistry, Faculty of Science and Technology, at Rajamangala University of Technology Thanyaburi (RMUTT), Thailand. Her research interest focuses on microencapsulation and Pickering emulsion for various applications.Piyaluk NgernchuklinPiyalak Ngernchuklin received the B.Sc. and M.Sc. degree in the field of Ceramic Technology, Material Science Department from Chulalongkorn University, Bangkok, Thailand, in 1998 and 2000, respectively. She worked as a senior researcher in the Expert Centre of Innovative Materials (InnoMat) of Thailand Institute of Scientific and Technological Research (TISTR) under Ministry of Science and Technology, Thailand. Currently, Piyalak's research interests include structure-processing-property relations in advanced ceramic materials (piezoelectric electrostricitive materials and their applications in actuator and sensor technology), and in advanced polymer materials.Amorn ChaiyasatAmorn Chaiyasat is an Associate professor at the Department of Chemistry, Faculty of Science and Technology, at Rajamangala University of Technology Thanyaburi (RMUTT), Thailand. He received a B.Sc. Chemistry degree (1996) from Mahasarakham University, Thailand, and M.Sc. Chemistry (2000) degree from Chiang Mai University, Thailand. He completed his Ph.D. program (2008) in the field of Materials Chemistry and Engineering from Kobe University, Japan. He spent a short time enhancing his knowledge of biopolymer research as a JSPS Postdoctoral Fellow, AIST Tsukuba, Tsukuba, JAPAN, in 2009, and a Visiting Scientist, McGill University, Montreal, CANADA, in 2012. His research focused on the conventional and reversible-deactivation radical polymerization in aqueous dispersed systems, preparation of polymer particle/capsule, and hybrid polymer particles.Preeyaporn ChaiyasatPreeyaporn Chaiyasat received B.Sc. (1997) and M.Sc. (2001) degrees in the field of Chemistry, Chemistry Department from Chiang Mai University, Chiang Mai, Thailand. She completed her Ph.D. program (2008) in the field of Materials Chemistry and Engineering from Kobe University, Japan. She worked as an Associate Professor in the Department of Chemistry, Faculty of Science and Technology, Rajamangala University of Technology Thanyaburi, Thailand. Currently, Preeyaporn research interests include polymerization in the aqueous dispersed system, micro- and nano-encapsulation, and biopolymer preparation for various applications.