A novel acrylate monomer was synthesized by facile sequential two-step reactions and polymerized using RAFT polymerization to yield a well-defined thermo-, pH- and CO2-responsive homopolymer.

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An AB 2 monomer PhBr 2 ACBCAPhACBCH containing one acetylene group and two bromide groups was efficiently synthesized by a strategy based on the different reactivity between aromatic iodide and bromide in Sonogashira reaction. The Sonogashira polymerization of PhBr 2 ACBCAPhACBCH was investigated to get hyperbranched poly(p-phenyleneethynylene-alt-mphenyleneethynylene) (hb-PMPE) in terms of the effects of monomer addition method, core molecule with different functionality, and ratio of INTRODUCTION Because of the highly branched and globular structure, hyperbranched conjugated polymers exhibit better solubility, thermal stability, and processibility than their linear analogues; therefore, it is much easier for them to form amorphous films of high quality and morphological stability. Moreover, the hyperbranched structure can enhance exciton confinement, suppress intrachain and interchain exciton annihilation, thereby, improve fluorescence quantum yields and electroluminescent efficiency significantly. 1 The global molecular shape can also induce efficient intramolecular energy transfer. [2][3][4] Hyperbranched conjugated polymers have attracted considerable attention as novel materials in the fields of light emitting, 5-23 solar cells, 24-26 fluorescent chemosensors, 27-32 and so on.

additional base since amines can act as both nucleophiles and bases, which means that the adducts can be accessed via easily mixing amines with activated olefins. Derived from the step-growth aza-Michael addition polymerization, the amine-containing polymers are generally pH-responsive and CO 2 -responsive, and they can usually be protonated and electropositive so as to interact electrostatically with negatively charged materials. [2,3,[10][11][12][13][14][15][16][17][18] In the case of thiol-Michael reactions, the thiols are the Michael donors. However, bases or nucleophiles as the catalyst are usually indispensable to make the addition smoothly occur. Thiol-Michael reaction has been used to form polymers from simple, ideal step-growth reactions of dithiol and divinyl monomers. The resulting thioether linkages in the backbone endow the polymers with unique characters such as a high degree of flexibility, oxidation-responsiveness, and a relatively high refractive index. [8,9,[19][20][21][22] Owing to the dual role of the amine in which it can directly add to activated olefins (nucleophile) and meanwhile catalyze the thiol-Michael reaction (base), the aza-and thiol-Michael reactions are anticipated to be carried out in a one-pot fashion and no additional catalyst is needed. This may be an effective polymer synthesis strategy because of the distinct advantages as mentioned above. Furthermore, due to the availability of appropriate amine and thiol derivatives, diverse functionalities from the monomers can be facilely incorporated into the polymer backbones, allowing the production of sophisticated macromolecular systems and offering the flexibility to tune their properties, which can largely enrich the functions and diversities of the polymers. Therefore, this strategy can serve as a powerful tool for the design and synthesis of multifunctional polymers. Surprisingly, to the best of our knowledge, even though tremendous efforts have been devoted to apply single type of Michael reaction for polymer synthesis, no example has been focused on the combination of them for synthesis of multifunctional polymers.Herein, we report for the first time the robust synthesis of multifunctional polymers via the combination of efficient azaand thiol-Michael reaction using the commercial diamine, dithiol, and diacrylate in one pot. Specifically, as shown in Scheme 1, the secondary amine undergoes an aza-Michael addition to poly(ethylene glycol) diacrylate (PEGDA) from Multifunctional PolymersThe combination of efficient and harmonious aza-Michael and thiol-Michael reactions in one pot is first reported for the convenient synthesis of thermo-, oxidation-, pH-, and CO 2 -responsive polymers. The simultaneous two-type Michael reactions are proved to proceed smoothly without additional catalyst. The dithiol and diamine are involved in the copolymerization competitively and thus in a random distribution. A wide range of commercially available starting materials are utilized for the simultaneous two-type Michael reactions in one pot to obt...