Sequence-Controlled Polymers With Furan-Protected Maleimide As A Latent Monomer

In the past century,life science has produced an epoch-making discovery,such as DNA sequencing,protein sequencing,Biological polymer materials with complex structure appeared continuously.Science then,scientists have become increasingly aware of the vital role of ordered sequences in functional expression of nature polymers.Obviously,this inspiration was captured by polymer chemists;they synthesized a variety of information loaded sequence-controlled copolymers to fully studied the relationship between the structure and function of sequence.Further,more novel properties or functions was endowed to precisely sequenced polymers.In this article,we have found a new method for preparing a sequence-controlled polymer with furan-protected maleimides as latent monomer.Latent monomer does not copolymerize with styrene,but under high temperature,retro Diels-Alder reaction readily happens and furan was removed from latent monomer,which undergoes rapid crosspropogation with styrene and the hetro polymer segement is obtained.Under the low temperature of 40 ?,the retro Diels-Alder reaction cannot happen,thus homo(polystyrene)segement was created.Therefore,in the controlled radical polymerization,with programmable changes of temperature(such as 40?-110 ?-40 ?-110 ?),the maleimide units can be placed at desired location along the"living" chain,thus the secquence-controll was realized.With St/maleimide/latent monomer,the sequence-controlled ternary polymerization was realized in one pot by using the programmable changes of polymerization temperature.The detailed studies were summarized as the following:1.There are many factors that affect the release rate of latent monomers,such as reaction temperature,concentration of latent monomers.We first explored the influence factor of rDA reaction.Then the effects of different conditions on the copolymer of latent monomer-styrene were investigated,and compared with naked maleimide-styrene copolymerization.It was verified that the latent monomer changed the sequence of maleimide and styrene.This work was carried out by one-pot method,and the samples drawn at determined time were characterized by 1H NMR,SEC and MALDI-TOF MS.2.The position of the maleimide unit was designed and encoded by designing programmable changes of temperature,such as 40 ?-110 ?-40 ?-110 ?.With St/maleimide/latent monomer,the sequence-controlled ternary polymerization was realized in one pot by using the programmable changes of polymerization temperature.Finally,we introduce a clickable alkynyl into the latent monomer,thus the alkynyl group can be placed at designed positions along the polymer chain by using this strategy.This work greatly enriched the research on sequence-controlled polymerization,providing a facile and efficient approach for creating sequence-controlled polymers.