Synthesis of Polyacrylate‐Based Polyurethane by Organocatalyzed Group Transfer Polymerization and Polyaddition

Abstract

AbstractThe current work describes the synthesis of novel polyacrylate‐based polyurethanes through the polyaddition of hexamethylene diisocyanate (HDI) with α,ω‐hydroxyl end‐functionalized polyacrylates (HO‐PA‐OHs), including α,ω‐hydroxyl end‐functionalized poly(n‐butyl acrylate) (HO‐PnBA‐OH), poly(n‐octyl acrylate) (HO‐PnOA‐OH), and poly(n‐lauryl acrylate) (HO‐PnLA‐OH), respectively. HO‐PA‐OHs are prepared by the N‐(trimethylsilyl)bis(trifluoromethanesulfonyl)imide (Me3SiNTf2)‐catalyzed group transfer polymerizations (GTPs) of n‐butyl acrylate (nBA), n‐octyl acrylate (nOA), and n‐lauryl acrylate (nLA) in toluene at room temperature using the functional 1‐(2‐triisopropylsiloxyethoxy)‐1‐triisopropylsiloxy‐2‐methyl‐1‐propene as an initiator and the low ceiling temperature acrylate, 2‐(triisopropylsiloxy)ethyl α‐phenylacrylate, as a terminator, followed by the desilylation of the resulting α,ω‐triisopropylsiloxy end‐functionalized polyacrylates (iPr3SiO‐PA‐OSiiPr3s) using tetra‐n‐butylammonium fluoride (TBAF). The polyaddition reactions between HO‐PA‐OHs and HDI are carried out in toluene using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) as the catalyst to afford the target polyacrylate‐based polyurethanes. The polymer structures are characterized by 1H NMR spectroscopy and FT‐IR measurements. The thermal properties of the resulting polyacrylate‐based polyurethanes are investigated by differential scanning calorimeter.