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Addition of a β-nucleating agent (β-NA) is the most effective method of preparing β-nucleated isotactic polypropylene (β-iPP); however, the poor dispersion and agglomeration of β-NAs limit nucleation efficiency. To solve this problem, a self-dispersing β-NA strategy was developed based on in situ preparation of β-NA (instead of pre-addition) during the processing of iPP. Zinc adipate (ZnAA), a typical...
An efficient metal-free bimolecular homodifunctional ring-closure method was developed specifically for preparing well-defined cyclic polymers from unconjugated vinyl monomers. In this approach, well-defined homodifunctional linear polymers with azide terminals were prepared by using the reversible addition chain transfer polymerization/macromolecular design by interchange of xanthates (RAFT/MADIX)...
A metal-free and efficient homodifunctional bimolecular ring-closure method was developed specifically for the formation of well-defined cyclic polyesters based on the combination of ring opening polymerization (ROP) and self-accelerating double strain-promoted azide-alkyne cycloaddition (DSPAAC) reaction. In this method, ROP and the following end group modification were used to prepare the azide-terminated...
Functional reversible addition-fragmentation chain transfer polymerization (RAFT) agent was developed to have a cyclopropenone-masked dibenzocyclooctyne end group. RAFT polymerization was then explored on three typical types of vinyl monomers in free radical polymerization such as styrene, methyl methacrylate, and tert-butyl acrylate. The living polymerization behaviors were demonstrated for all three...
Perforated lamellar (PL) microphase structure of block copolymers in the bulk is rarely observed. Herein, formation of the PL structure from simple block copolymer, poly(tert-butyl methacrylate)-block-polystyrene (PtBMA-b-PS) prepared by reversible addition–fragmentation chain transfer (RAFT) mediated radical polymerization, is reported. The PL phase consists of alternating layers of PS and PtBMA...
Topological polymers with T-shaped and H-shaped molecular architecture were built on the combination of atom transfer radical polymerization (ATRP) and UV-induced strain promoted azide-alkyne cycloaddition (SPAAC) reaction. In the presence of a cyclopropenone-masked dibenzocyclooctyne functionalized dibromo ATRP initiator, reactive polystyrene (PS) was synthesized to have a cyclopropenone-masked dibenzocyclooctyne...
The modulatory effect of oligoguluronate (GB) on the gelation of macromolecular alginate (ALG) was investigated by means of dynamic oscillatory rheology, fluorescence and AFM measurements. An inhibitory effect in the range of 0.25 < R (Ca/G) < 0.60 and a promotive effect in the range of R > 0.60, were quantified. The two effects are thought to be associated with the different molecular events...
Triazolinedione (TAD) based Alder-ene reaction was demonstrated as a unique method to efficiently post-functionalize the well-defined polymers derived from living ring-opening metathesis polymerization (ROMP). Using 4-nitrophenyl-1,2,4-triazoline-3,5-dione (p-NO2-PhTAD) as a model TAD compound to react with the double bonds in the backbone of ROMP polymers, the model polymer of poly(N-propyl-5-norbornene-exo-2,3-dicarboximide)...
Two functional atom transfer radical polymerization (ATRP) initiators (I-2 and I-3) were developed bearing a cyclopropenone-masked dibenzocyclooctyne group. ATRP was then explored on three main kinds of monomers for radical polymerization including acrylates, styrenics, and methacrylates based on these novel initiators. By a standard ATRP protocol, the polymerization behavior demonstrated the living...
Recently it was reported that C(sp 3 )Br–C(sp 3 )Br homo-coupling reactions may be occurred efficiently catalyzed by Ni(II) in the presence of Zn. In this work, we applied this reaction for polymerization of alkyl dibromides. It was shown that 1,4-dibromobutane may polymerize by this coupling polymerization to afford polybutenes with low molecular weight. Then dl-1,4-dibromo-2,3-diphenylbutane,...
Poly(ethylene oxide)-block-poly(2-(diethylamino)ethyl methacrylate) (PEO-b-PDEAEMA) diblock copolymer was synthesized by anionic polymerization, whose molecular structure was characterized by 1H NMR and size exclusion chromatography (SEC). The diblock copolymer self-assembled into micelles in nonacid aqueous solution with PEO and PDEAEMA as corona and core respectively. By virtue of the coordinating...
Strain-promoted azide-alkyne cycloaddition “click” reaction (SPAAC) was successfully used as a tool in synthesis of star polymers by grafting onto approach. The application of SPAAC method in star polymer synthesis was investigated for coupling reaction of the dibenzocyclooctyne (DIBO) end group of polystyrene (PS) and poly(ethylene glycol) (PEG) with coupling agents bearing 2, 3, or 4 azido groups...
The dibenzocyclooctyne end functionalized agent 1 was designed as atom transfer radical polymerization (ATRP) initiator. The ATRP was then explored on three types of monomers widely used in free radical polymerization: methyl methacrylate, styrene, and acrylates (n-butyl acrylate and tert-butyl acrylate). The living polymerization behaviors were obtained for the methyl methacrylate and styrene monomers...
Hairy polymer nanoobjects (PNOs) of different shapes can be easily obtained by cross-linking the discontinuous microphases of bulk block copolymers followed by dispersing in a solvent. Herein we report a general approach to functionalize the shaped PNOs by bulk microphase separation of poly(3-(triethoxysilyl)propyl methacrylate)-block-polystyrene (PTEPM-b-PS) copolymers in the presence of functional...
A functional gelable triblock copolymer, poly(2-vinylpyridine)-block-poly(3-(triethoxysilyl)propyl methacrylate)-block-polystyrene (P2VP-b-PTEPM-b-PS), was prepared by the combination of reversible addition-fragmentation chain transfer (RAFT) mediated radical polymerization and copper catalyzed click chemistry. Bulk microphase separation of P2VP 310 -b-PTEPM 58 -b-PS 322 under...
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