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ABSTRACT In this contribution, we reported a facile synthesis of poly(methyl methacrylate)- block-poly( N-vinyl pyrrolidone) (PMMA- b-PVPy) diblock copolymers via sequential radical polymerizations mediated by isopropylxanthic disulfide (DIP). It was found that the radical polymerization of N-vinyl pyrrolidone (NVP) mediated by DIP was in a controlled and living manner. In contrast, the polymerization of methyl methacrylate mediated by DIP displayed the behavior of telomerization, affording xanthate-terminated PMMA with a good control of molecular weights while the conversion of monomer was not very high. The xanthate-terminated PMMA can be successfully used as the macromolecular chain transfer agent for the polymerization of NVP via RAFT/MADIX process and thus PMMA- b-PVPy diblock copolymers can be successfully synthesized via sequential radical polymerization mediated by isopropylxanthic disulfide. One of these diblock copolymers was incorporated into polybenzoxazine and the nanostructured thermosets were obtained as evidenced by transmission electron microscopy, small angle X-ray scattering, and dynamic mechanical thermal analysis. The formation of nanostructures in polybenzoxazine thermosets was ascribed to a reaction-induced microphase separation mechanism. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 952-962 [ABSTRACT FROM AUTHOR]

Functionalization of chain terminals of hyperbranched polymer can be both beneficial and challenging due to the large number of terminals originating from the hyperbranched architecture. Direct terminal functionalization is even more difficult for hyperbranched polyolefin via coordination polymerization due to the compatibility of the catalytic system and some terminal functionalization reagents. To overcome this issue, herein we report the synthesis of hyperbranched polyolefins via ring-opening metathesis polymerization from a substituted cyclooctene monomer with bi-functional acyclic olefin as chain-transfer agent via one-pot process. We envision that this work will provide a new route for the synthesis of functional hyperbranched polyolefin materials. The synthesis of terminal functionalized hyperbranched polyolefin via ROMP with a branched monomer and chain-transfer agents (repeating units of the hyperbranched olefin are placed between brackets). [Display omitted] • Synthesis of hyperbranched polyolefins via ROMP with various types of chain terminals. • One-pot synthetic method with ROMP and cross-metathesis reaction performing together. • Functional hyperbranched polyolefin materials with high degree of branching. [ABSTRACT FROM AUTHOR]

A new kind of hyperbranched semi-aromatic poly(ester-imide)s with hydroxyl terminated groups has been prepared from commercially available 1,2,4-benzenetricarboxylic anhydride (TMA) as the AA′-type aromatic monomer and 3-amino-1,2-propanediol (3APPD), 2-amino-1,3-propanediol (2APPD), N,N-bis(2-hydroxyethyl)ethylenediamine (BHED) as CB 2 -type aliphatic monomers via a simple one-pot melting polymerization method. The effects of synthesis conditions on the structures and properties of the products were investigated in detail. The combination of FTIR, 1H NMR, 2D NMR, MALDI-FTICR-MS and model reactions have been used to characterize the structures of the obtained polymers. As assessed using thermal measurements, the obtained hyperbranched semi-aromatic poly(ester-imide)s possess low glass transition temperature (≤120 °C) and high thermostability with an onset decomposition temperature ranging from 355 to 420 °C in nitrogen. The products possess abundant terminal hydroxyl functional groups. Hydroxyl values vary between 198 and 248 mg KOH/g depending on the particular precursors used to generate the polymers. The synthesis of hydroxyl terminated hyperbranched semi-aromatic poly(ester-imide)s. [Display omitted] • Hyperbranched semi-aromatic poly(ester-imide)s were prepared by one-pot melting polymerization. • HBPEIs possess low T g and high thermostability. • HBPEIs are terminated by abundant hydroxyl function groups. • This synthetic strategy exhibits good fault-tolerant ability for reaction condition. [ABSTRACT FROM AUTHOR]