Hydrogen bond between molecules is a very important weak interaction. Hydrogen bonding has been applied to the controlled radical polymerization(CRP)system to achieve the dual control of molecular weight and stereoregularity

which makes the precision syntheses of polymers possible. However

the exact reason for the molecular weight control has not yet been realized. In the recent years

our group has focused on the hydrogen bonding induced controlled radical polymerization of methyl methacrylate

4-vinyl-pyridine and 2-vinyl-pyridine. Control over molecular weight

tacticity and monomer sequence have been realized. Importantly

for the first time

the systematic research revealed that the hydrogen bonding can activate the monomer by electron induction interaction. The concept of hydrogen bonding promoting CRP or monomer-activating effect undoubtedly opened a new avenue to improve the controllability of those less active monomers.