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A new mending chemistry exhibiting stability at extreme temperatures and holding mechanical properties as well as mechanical stability comparable to widely used engineering plastics is reported here. This mendable thermoset polymer is synthesized using commodity reactants through the formation of an isocyanurate-oxazolidone network which exhibit a high service temperature as shown by their Tg of 270 °C...
Two kinds of ethylene-α-octene copolymers (ethylene-α-octene block copolymer, OBC, and ethylene-α-octene random copolymer, ORC) and their composites with MWCNTs were investigated by means of various solid-state NMR techniques. 13C MAS NMR revealed that there were only orthorhombic crystals in OBC composites, which resulted in stronger volume exclusion effect towards MWCNTs than that in ORC composites...
An intrinsic high-barrier and thermally stable polyimide (2,7-CPPI) was prepared by the polymerization of pyromellitic dianhydride (PMDA) and novel diamine (2,7-CPDA), which consists of rigid planar carbazole moiety. The resulted 2,7-CPPI exhibits excellent barrier properties, with oxygen transmission rate and water vapor transmission rate low to 0.2 cm3 m−2·day−1 and 0.1 g m−2·day−1, respectively...
A novel amphiphilic four-arm star copolymer [poly(ε-caprolactone)-b-poly(poly(ethylene glycol) methyl ether methacrylate-co-p-(2-methacryloxyethoxy) benzaldehyde)]4 [4-AS-PCL-P(PEGMA-co-MAEBA)] was designed and synthesized by a combination of ring-opening polymerization (ROP) and continuous activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP). Stimuli-responsive...
An asymmetrical building block-TBF modified with alkylthio phenyl as the side chain, polymerization with 4, 7-di (5-bromothiophen-2-yl)-5, 6-dioctyloxybenzo[c] [1,2,5]thiadiazole (BT), a new polymer-TBFPS-BT was obtained. As described in the UV-Vis spectrum, TBFPS-BT exhibited good absorption covering from 300 to 750 nm. Benefited from the alkylthio phenyl substitution, the polymer possessed deep...
Surface free energy and surface reorganization, two essential properties for low surface free energy materials, have been researched by studying the effects of the groups (H or CH3) at α-position and the side-chain structures (flexible or rigid) of alkyl (meth)acrylate on a series of fluorinated copolymers poly (perfluorohexylethyl methacrylate)-co-poly [alkyl (meth)acrylate]. The static contact angle,...
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...
The low dielectric constant (εr ∼ 3–4) for semiconducting polymers has been a major cause for their poor performance compared with the inorganic semiconductors, which possess high dielectric constants above 10. This study aimed to increase the electronic/atomic dielectric constant at high frequencies (i.e., εr∞) for semiconducting polymers. A new design strategy was proposed based on the electric...
Rod-like mesoporous SBA-15 silica particles were surface modified by different silane coupling agents firstly, then polymethyl methacrylate (PMMA) was prepared in the confined nanopores of the SBA-15 via activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP). The PMMA/SBA-15 nanocomposites and PMMAs inside the nanopores were characterized by X-ray powder...
In the present investigation, we explore the influence of uniaxial orientation and subsequent thermal annealing on semi-crystalline poly(ethylene-tetrafluoroethylene) (ETFE) microstructure and dynamics, and the connection to dielectric breakdown strength. Understanding the influence of crystalline microstructure on dynamics and breakdown, and in turn how processing influences microstructure, is critical...
Hierarchical assembly of macromolecules has been central in creating complex nanostructures. In this work, polystyrene-block-poly (perfluorooctylethyl acrylates) (PS-b-PFOA) diblock copolymers were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and shown to assemble into hierarchical structures in bulk with the interplay of nanophase separation and crystallization...
In this study, we report the design and synthesis of two donor−acceptor isoindigo dye-based copolymers, namely PIIVS1 and PIIVS2, in which π−extended diselenophenylethene building block acts as electron-donating units. The charge transport properties of both copolymers were studied by fabricating field-effect transistors (FETs). The two copolymers-based FETs with electrodes modified by thiol self-assembled...
Antioxidant in form of hindered phenol structure is commonly used to prolong the service life of polymer, while the low molecule antioxidant has defect for its low thermal stability and physical loss. Herein, the feasibility of using co-condensed silica immobilized antioxidant (denoted as SN-NH2-AO) to improve the thermal-oxidative stability of polypropylene (PP) was evaluated. Firstly, SN-NH2-AO...
In our previous work, poly(butyl acrylate) (PBA) latex microspheres (LMs) were embedded within hydrogels to enhance their mechanical strength. Herein, acrylonitrile (AN) components were added to the latex system to prepare novel poly(butyl acrylate-acrylonitrile) (P(BA-AN)) LMs. LMs were able to adsorb hydrophobic hexadecyl methacrylate (HMA) due to hydrophobic interactions, stabilized by using sodium...
A novel compound diethyl acetylphosphonate has been explored as efficient additive in iron based catalyst for stereo-polymerization of 1,3-butadiene to afford high crystalline 1,2-syndiotactic polybutadiene. Excellent 1,2 selectivity in range of 91.0–98.4% with controllable crystallinity has been achieved at high catalytic efficiency in wide ranges of cocatalyst and additive feeding as well as at...
Increasing temperature has been widely considered as a primary and effective way to improve the segmental mobility of polymer chains and subsequently cause polymer chains to flow. Here, by confining the morphology of polymers into nanospheres and combining this process with external stress, we present an important new approach to achieve the cold flow of glassy polymers at room temperature, under...
Crystalline polymers can exhibit anomalous crystallization behaviors as restricted into nanodomains. Herein, syndiotactic polypropylene (sPP) was infiltrated into nanoporous alumina templates with different pore diameters, and their nonisothermal and isothermal crystallization kinetics were investigated. As located inside nanopores, the crystallization of sPP becomes sluggish. The crystallization...
An off-lattice dynamics Monte Carlo method is used to study the conformations of self-attractive semiflexible ring chains. The conformations depend mainly on the bending energy b and the self-attractive interaction ε of ring chains, and perfect helical structures are found in self-attractive semiflexible ring chains with the moderate attractive interaction ε. Some monomers of the semiflexible ring...
Poly(2-hydroxyethyl methacrylate) (PHEMA) films with gradient crosslinking density are the only hydrogel films capable of generating regular wrinkling patterns upon swelling, however, they were synthesized via a complicated two-stage photopolymerization. In an effort to develop a simple synthesis method, we found that one-step UV-curing of HEMA liquid always results in films with corrugated surface,...
The core-shell polyelectrolyte complexes chitosan (CS)/hyaluronic acid (HA) nanofibers could be produced from electric field inducing phase separation during the progress of electrospinning. The morphology of core-shell nanofibers was supported using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The presence of CS on the shell of the nanofibers was also verified by...
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