Versatile morphology transition of nano-assemblies via ultrasonics/microwave assisted aqueous polymerization-induced self-assembly based on host-guest interaction

Dan Li; Xin Shao; Xin Li; Yongqiang Qian; Guxia Wang; Yen Wei; Shengwei Guo

doi:10.1016/j.ultsonch.2024.106901

Versatile morphology transition of nano-assemblies via ultrasonics/microwave assisted aqueous polymerization-induced self-assembly based on host-guest interaction

Ultrason Sonochem. 2024 May 9:106901. doi: 10.1016/j.ultsonch.2024.106901. Online ahead of print.

Authors

Dan Li¹, Xin Shao¹, Xin Li¹, Yongqiang Qian¹, Guxia Wang², Yen Wei³, Shengwei Guo⁴

Affiliations

¹ International Scientific and Technological Cooperation Base of Industrial Solid Waste Cyclic Utilization and Advanced Materials, Key Laboratory of Polymer Materials and Manufacturing Technology, School of Materials Science and Engineering, North Minzu University, Yinchuan 750021, PR China.
² School of Chemistry and Chemical Engineering, North Minzu University, Yinchuan 750021, PR China. Electronic address: guxia511@163.com.
³ International Scientific and Technological Cooperation Base of Industrial Solid Waste Cyclic Utilization and Advanced Materials, Key Laboratory of Polymer Materials and Manufacturing Technology, School of Materials Science and Engineering, North Minzu University, Yinchuan 750021, PR China; Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing 100084, PR China.
⁴ International Scientific and Technological Cooperation Base of Industrial Solid Waste Cyclic Utilization and Advanced Materials, Key Laboratory of Polymer Materials and Manufacturing Technology, School of Materials Science and Engineering, North Minzu University, Yinchuan 750021, PR China. Electronic address: shengwei@nun.edu.cn.

PMID: 38735786
DOI: 10.1016/j.ultsonch.2024.106901

Abstract

Nano-assemblies have wide applications in biomedicine, functional coatings, Pickering emulsifiers, hydrogels, and so forth. The preparation of assemblies mainly utilizes the polymerization-induced self-assembly (PISA) method, which can produce high-concentration nanoscale assemblies in one step. However, the initiation processes of most reported PISA are limited to thermal initiation. Here, we reported two green and efficient methods for synthesizing nano-assemblies with various morphologies using ultrasound (20 kHz)/ microwave (500 W) assisted aqueous-phase RAFT-PISA in 3 h and 1 h. Cyclodextrin (CD) and styrene (St) nucleating monomer were complexed in a 1:1 ratio. Then, using Poly (ethylene glycol) methyl ether as the macromolecular reversible addition-fragmentation chain transfer (RAFT) agent (PEG-CTA) to control the CD/St complexes, the conversion rate of St monomer was respectively 27 %-60 %, 20 %-30 % within 3 h and 1 h under ultrasonics/microwave assisted PISA. Results showed that the morphologies of the assemblies are not only related to the length of PS block, but also to the assistance types and the remaining monomer concentration. The results showed that only PEG₄₅-b-PS₉₀ and PEG₄₅-b-PS₂₄₁ assemblies prepared by ultrasonics assisted PISA form evolved lamellaes and vesicles (100 nm), which break through the limitation of kinetic freezing. But the ultrasonic reaction on morphology of assemblies is not all favourable. For one thing, it can promote the movement of particles; for another, it makes reverse morphology transformation and sphere is preferred morphology. Therefore, the main reason of morphology evolution is the remaining monomer concentration of PEG₄₅-b-PS₉₀ and PEG₄₅-b-PS₂₄₁ assemblies reaches to 55 %-65 %, which promoting the segment movement. The results showed that the morphology of the assemblies prepared by microwave assisted PISA changed from spherical micelles to short rods, and finally to vesicles (120-140 nm) as the length of hydrophobic PS block increases. The kinetic freezing problem was solved in microwave-assisted PISA due to the action of microwaves and more remaining monomer concentration. Both them can boost particles movement.

Keywords: Microwave; Nano assemblies; Polymerization-induced self-assembly; Ultrasonics; Versatile morphology transition.