Study On The Preparation Of Nanoencapsulated Phase Change Materials Via Miniemulsion Polymerization

Miniemulsion polymerization is an important method to prepare nanocapsules PCM,but traditional emulsifier used in miniemulsion is easy to fall off from the surface of capsules,reducing the stability of the emulsion.In order to solve this proplemb,the article studies on the preparation of nanocapsules coating PCM using ploymerizable emulsifier via miniemulsion polymerization, ploymerizable emulsifier can react with monomer, improving the stability of the emulsion.Frist, we explore the effect of ploymerizable emulsifier HEC16on the encapsulated paraffin with polystyrene as shell. The results show that HEC16is easy to be copolymerized with styrene; nanocapsules with unimodal particle distribution and shell-core structure can be obtained using HEC16.Secondly, we mainly study the effect of the ploymerizable emulsifier AOS on the encapsulated paraffin with polystyrene as shell. The morphology, structure and thermal properties of nanoencapsulated PCM prepared with different amount of AOS,cross-linking agent,chain transfer agent,co-stabilizer,hydrophilic comonomer,and paraffin are discussed. The results show that shell-core structure can be obtained with AOS,and when the cross-linking agent,chain transfer age,hydrophilic comonomer and PCM/monomer are the optimal dosage, encapsules with particle size about100nm, unimodal particle distribution and shell-core structure can be obtained.In the end, the article investigates the freeze-thaw, machinery, electrolyte resistance, storage stability and the shell strength of nanocapsules prepared by AOS.The results show that nanocapsules prepared by AOS have better stability than that prepared by LAS.The Heating/cooling cycle experiments indicate that the nanocapsules are strong enough to resist stress caused by the change of volume causing by the phase change.