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The diffusion of polymer in long cylindrical tubes is investigated by using Monte Carlo simulations. Two kinds of cylindrical tubes are taken into account: (1) a homogeneous tube where the polymer-tube interaction is independent of monomer position along the longitudinal direction of the tube, and (2) a periodic one where the interaction is periodically changed along the tube. In the homogeneous tube,...
The alternating copolymerization of one-carbon (C1) building blocks including carbon dioxide (CO2) and its sulfur analogues of carbon disulfide (CS2) and carbonyl sulfide (COS) with epoxides afford new copolymers, namely polycarbonates and polythiocarbonates, with tailored chain structures and properties. This review mainly focuses on the recent advances in C1-involved copolymerization via heterogeneous...
Amphiphilic polyrotaxane (PR)-based block copolymers are synthesized by end-capping polypseudorotaxanes (PPRs) formed from distal 2-bromopropionyl terminated Pluronic F68 and a varying amount of β-cyclodextrins (β-CDs) using hydrophilic polymeric blocks of poly(ethylene glycol) methyl ether methacrylate (PEGMA) yielded via the in situ ATRP. To gain a tumor-targeting nano doxorubicin (DOX) delivery...
The radical-mediated addition of trimethylolpropane trimethacrylate (TMPTMA) to linear, isotactic polypropylene (PP) yields graft-modified derivatives that contain coagent-rich, cross-linked particles with sub-micron dimensions. The presence of this dispersed phase in coagent-modified polypropylene (CM-PP) is shown to increase the crystallization temperature and crystallization rate, owing to an enhanced...
Multi-walled carbon nanotubes (MWCNTs) filled poly(l-lactic acid) (PLLA) and PLLA/poly(d-lactic acid) (PDLA) composites were prepared through a directly melt mixing process. A special crystalline structure of stereocomplex was formed by PLLA and PDLA, which was easily found when mixing two polymers with identical chemical composition but different steric structures. The electrical conductivities were...
A series of polyrotaxane (PR)-based triblock copolymers comprising a PR middle block and poly(n-butyl methacrylate) (PBMA) flanked blocks were prepared via bulk ATRP of n-butyl methacrylate initiated with polypseudorotaxanes self-assembled from α-cyclodextrins (α-CDs) with 2-bromoisobutyryl terminated Pluronic 17R4 at 35 °C. Their structure was verified by 1 H NMR, FTIR, GPC, WXRD and TGA...
Biodegradable polyrotaxane (PR)-based triblock copolymers were synthesized via the atom transfer radical polymerization (ATRP) of N-isopropylacrylamide (NIPAAm) initiated with polypseudorotaxanes (PPRs) consisting of a distal 2-bromopropiomyl bromide end-capping poly(ε-caprolactone) (Br-PCL-Br) and a varying amount of α-cyclodextrins (α-CDs) in the presence of Cu(I)Br/PMDETA at 25 °C in aqueous solution...
It was reported that polyrotaxanes (PRs) comprising β-cyclodextrins (β-CDs) and Pluronic F127 end-capped with poly(N-isopropylacrylamide) blocks show a β-CD aggregated state in which the threaded β-CDs are self-aggregated into a typical channel-type crystal structure after water incubation. At the same time, they converse into a β-CD dispersed state in which the entrapped β-CDs are randomly dispersed...
The molecular structure of polyaluminocarbosilane (PACS) derived from polycarbosilane (PCS) was investigated by 1 H, 29 Si, 27 Al NMR and elemental analyses. Quantitative methods based on experimental data were established to determine the exact amounts of O-containing groups, namely Si−O−Al and Si−O−Si, and the relative numbers of linear and cyclic Si−C segments in PACS. The...
Herein novel polyrotaxanes (PRs) comprising γ-CDs and Pluronic F127 end-capped using poly(N-isopropylacrylamide) blocks were prepared via the atom transfer radical polymerization in aqueous medium at room temperature. The structure was characterized in detail by 1 H NMR, 2D NOESY NMR, FTIR, GPC, WXRD and DSC analyses. Solvent treatments were conducted on the resulting PRs via incubation in...
A kind of novel amphiphilic triblock copolymers containing polyrotaxane (PR) as a central block was synthesized via the ATRP of poly(ethylene glycol) methyl ether methacrylate (PEGMA) initiated with polypseudorotaxanes made from a distal 2-bromopropionyl end-capped Pluronic F127 with a varying amount of β-CDs in the presence of Cu(I)Cl/N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA) at 25°C in...
The first combined use of reversible addition–fragmentation chain transfer (RAFT) polymerization and precipitation polymerization in the molecular imprinting field is described. The new polymerization technique, namely RAFT precipitation polymerization (RAFTPP), provides MIP microspheres with obvious molecular imprinting effects towards the template, fast template binding process and an appreciable...
A novel strategy for the preparation of main-chain polyrotaxanes with lengthily tunable PHEMA as outer bulky stoppers was described in the present study. Polypseudorotaxanes made from the self-assemblies of a distal 2-bromoisobutyryl end-capped PEG with a varying amount of α-CDs in aqueous media were used as macroinitiators in situ to initiate the ATRP of HEMA catalyzed by Cu(I)Br/PMDETA at room temperature...
In the present study we describe a synthesis and self-assembly and an in vitro evaluation of a kind of novel amphiphilic glycopeptide block copolymers as carriers for controlled drug release. Initially, an amphiphilic ABA triblock copolymer comprising polytetrahydrofuran (PTHF) as a central hydrophobic block flanked by poly(l-lysine)s (PLLs) as outer hydrophilic blocks was synthesized through the...
Brush copolymers synthesized by controlled radical polymerizations were crosslinked either covalently or physically, resulting in elastomers with an unusually low equilibrium shear modulus G e , of order 1kPa. Examples are given for both crosslink motifs, along with the dynamic viscoelastic properties of these materials. The results are discussed in terms of the effect of the side chains on...
A protocol for the preparation of novel triblock copolymers comprising a polyrotaxane center block and outer blocks of poly(N-isopropylacrylamide) (PNIPAAm) as bulky stoppers was developed, in which N-isopropylacrylamide was allowed to telomerize in the presence of polypseudorotaxanes made from the self-assembly of thiol end-capped PEG with a varying amount of α-CDs under UV irradiation in aqueous...
The growth of banded hedrites of isotactic polystyrene (iPS) is followed in situ, using atomic force microscopy (AFM). The melt layer surrounding the growing hedritic front is much thinner than both the hedrite front and the far-field melt. Growth occurs simultaneously in three dimensions: radially, circumferentially and height. The height of the hedrite growth front being so much higher than the...
A study of the changes in crystal perfection of polyamide 66 (PA66) and polyamide 66/clay nanocomposites (PA66CN) due to different thermal processing was carried out. We designed three series of thermal processing including melt-quench (MQ), post-annealing MQ sample (MQA), and melt–slow cooling–annealing (MSA). The annealing temperature was set as 180 or 210°C, which is within Brill temperature range...
Melts of linear brush polymers with PEO side chains attached at each repeat unit of the backbones have been doped with CF 3 SO 3− Li + . Mechanical properties and ionic conductivity of such systems have been analyzed using mechanical and dielectric spectroscopies. Mechanical spectra indicated a presence of super soft states for samples with long backbones or for systems...
The effects of the molecular weight of polystyrene (PS) component on the phase separation of PS/poly(4-vinylpyridine) (PS/P4VP) blend films on homogeneous alkanethiol self-assembled monolayer (SAM) and heterogeneous SAM/Au substrates have been investigated by means of atomic force microscopy (AFM). For the PS (22.4k)/P4VP (60k) system, owing to the molecular weight of PS component is relatively small,...
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