Due to the unique double-or multiple-chain structure

Ladder-like polysiloxanes (R-LPSs) have shown much higher resistance to heat

oxidation and radiation than the corresponding single-chain polysiloxanes. Since the first report in 1960s by Brown

R-LPS has attracted a lot of attention worldwidely

and great efforts have been made in synthesis novel R- LPS and enhance the regularity of the ladder structures since then. With the deepening understanding of the no chemical bonded inter-molecular interaction

the synthesis mechanism of R-LPS has also been further developed. It involves broad theoretical and experimental research in polymer frontiers

such as supramolecular assistant synthesis method

ladder macromolecular formation mechanism

nanostructure and material properties characterization

etc. This paper first gives an overall introduction of R-LPSs

and then reviews the most recent progress in this field. Especially

this paper reviews the publications on the synthesis of R-LPS based on the "super-molecular coupling and the gradually build-up polymerization". The R-LPSs in this review are generally classified based on structure of the main chain as three categories : Radical-sided double-chain-bonded ladder polysiloxane (R-DLPS)

Radical-sided triple-chain-bonded organo-bridged ladder polysiloxane (R-TLPS) and Radical-sided quadruple-chain-bonded ladder polysiloxane (R-QLPS). Synthesis and characterization of R- LPSs with different side groups are demonstrated. The cited papers are mostly published in the nearest five years.