Research progress in polyelectrolyte complexes based on layer-by-layer self-assembly technology and their applications

Abstract

Polyelectrolytes (PEs) are a class of polymers with ionizable groups on molecular chains and could dissociate into a highly charged polymeric molecule in ionizing solvent. According to their surface charges, PEs can be classified into three groups: cationic PEs, anionic PEs and amphoteric PEs. PEs have received the attention of scientists for nearly a century ever since the discovery that some natural PEs could interact in water to form colloidal complexes known as polyelectrolyte complexes (PECs). PECs with three-dimensional macromolecule structure can be formed by mixing opposite charged PEs in solution. Formation of PECs will significantly influence the solubility, rheology, turbidity and conductivity of polymer solution and as-formed PECs contain the feature of stimulus responsiveness to change of external environment. Layer-by-layer self-assembly (LBL) of multilayers based on alternately adsorbing opposite charged PEs or multi-charged molecules on solid surfaces is a simple and multifunctional interface supramolecular self-assembly technology that developed in 1990 s. With the application of LBL technology, PECs with certain structures and properties are designed and are widely used in different kinds of industry. This review focuses on the preparation method, formation mechanism, influencing factors of PECs based on LBL technology. In addition, applications of PECs in nanoreactors, drug release, biosensor and fabric flame retardant fields were also summarized. Finally, it was pointed out that future research will focus on simplifying the production process, accurately controlling over the structure and realizing the multi-function of PECs.

Keywords

• polyelectrolyte complexe
• layer-by-layer self-assembly
• drug release
• biosensor
• flame retardance