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Inspired by the nature material, a crosslinked network structure of polyurethane/epoxy resin composite material was built through Diels-Alder (DA) reversible covalent bond reaction between the dienes and dienophile group on the side chain of epoxy resin and polyurethane respectively. The synthesized composite material combined the advantages of polyurethane and epoxy resin. The hard segments of polyurethane...
Polymer migration to the film surface during the melt processing of polymer blends is an important phenomenon, but has been limited in study. In this work, melt extruded cast films of conductive poly (ether-block-amide) (PEBA) with low-density polyethylene (LDPE) and polystyrene (PS) are prepared and the critical roles of phase continuity, interfacial tension and viscosity on PEBA surface migration...
Porous conjugated polymers have emerged recently as efficient metal-free and visible light-active photocatalysts. However, the synthesis of this new class of materials usually requires transition metal catalysts such as palladium. A metal-free synthetic route still remains a huge challenge for the chemists. Here we report on a metal-free pathway of a porous conjugated polymer via simple Knoevenagel...
There is much need in advancing rational design of synthetic cationic polymers as gene carriers. Inspired by the molecular blueprint of the famed branched polyethylenimine (bPEI), here we describe a new series of acid-labile branched poly(ortho ester amino alcohol)s (bPOEAAs) that embodies multiple design principles about polymer degradability, chain branching, and type of cationic amino groups. The...
Herein, acid-degradable poly(ortho ester urethanes) (POEUs) were synthesized via polycondensation between an acid-labile ortho ester diamine and active esters of poly(ε-caprolactone) (PCL) diols with different molecular weights. The POEUs nanoparticles were easily fabricated using an oil-in-water emulsion technique, whose ortho ester bonds in main-chains could be degraded at different rate in acidic...
PEGylated poly(ortho ester amides) copolymer micelles (POEAd-g-MPEG micelles) with ultra-pH-sensitivity, which exhibited a dynamic change in size under mildly acidic conditions, were constructed by facile method, therefore achieving: (i) remaining stealthy and long-circulating in the blood; (ii) small NPs once in the tumor extracellular space for enhancing penetration; (iii) bigger NPs after penetration...
Copper contamination results in poor stability and limited application of latexes generated using emulsion ATRP. This work describes an electrolysis method, which provides for the removal of copper from such latexes, while preserving colloidal stability and latex particle integrity. Polyacrylate latexes were synthesized via emulsion polymerization with reverse ATRP. The reaction was mediated by CuCl...
The connection between the structures and the linear viscoelasticity was revealed in this work for polymer nanocomposites containing agglomerated particles. A new image analysis method using the greyscale histogram of TEM images was suggested to determine the local volume fraction of nanoparticles inside an agglomerate, which represents the degree of agglomeration. It is found that the local volume...
A new type of linear copolymers, poly(ortho ester amino alcohols) (POEAAs), has been synthesized by ring-opening polymerization between diglycidyl ethers and amine monomer with ortho ether bonds. POEAAs have uniform distribution of tertiary amine main-chains along with abundant hydroxyl groups and acid-cleavable tertiary amine side-chains. POEAA1 and 2 containing different diglycidyl ether moieties...
Two novel asymmetrical carbazole-based diamines 9-(2-(1,1′-binaphthyl-4-yl)benzyl)-9H-carbazole-3,6-diamine (BNBCD) and 9-((4′-(9H-carbazol-9-yl)biphenyl-2-yl)methyl-9H-carbazole-3,6-diamine (CBMCD) were synthesized. A series of novel soluble aromatic polyimides were prepared from these diamines by poly-condensation with Pyromelitic dianhydride (PMDA) and 2,2′,3,3′-biphenyl tetracarboxylic dianhydride...
We have investigated phase behaviors of a series of polyphenylacetylene derivatives, poly[di(n-alkyl) ethynylterephthalates] (Pn, n is the number of carbon atoms of n-alkyl group, from 2 to 14), which are largely influenced by the length of n-alkyl tails on 2,5-position of the phenyl group. With short alkyl groups (n ≤ 6), Pns form columnar liquid crystalline (Col) phases due to the “jacketing effect”...
The elastomeric performance of a series of ethylene/1-octene random and block copolymers prepared from living coordination polymerization was studied in this work. All the polymer samples exhibited good toughness. The living random copolymers had better elasticity than commercial metallocene random copolymers. The strain recovery of the living random copolymers was about 90% with an applied strain...
Hierarchically porous polymers with controllable pore size were generated through a novel polymer blending strategy in an A/B/C–B–C ternary blend system. Polylactide/high-density polyethylene/poly(styrene-ethylene/butylene-styrene) triblock copolymer (PLA/HDPE/SEBS) was used as a model system to demonstrate this technique. During melt blending, the SEBS was driven into the HDPE phase owing to the...
A new type of acid-labile cationic copolymer consisting of a hydrophilic poly(ethylene glycol) (PEG) block and a polymethacrylamide block bearing tertiary amines linked by acid-labile ortho ester rings in side chains (PAOE), with defined chain length, had been synthesized via RAFT polymerization. The copolymers could efficiently bind and condense plasmid DNA at neutral pH into narrowly dispersed nano-scale...
The dissipative particle dynamics (DPD) is used to study the compatibilizing process of an immiscible polymer blend using a graft copolymer as a compatibilizer. Polystyrene (PS) and polyamide 6 (PA6) are chosen as the polymer components of the blend. The graft copolymer is composed of PS as the backbone and PA6 as the grafts. Mesoscale morphology, density distribution, end-to-end distance of PA6 and...
The self-assembly and photophysical properties of a triblock copolymer with complex mid-block in THF and aqueous solution were investigated in this research. Poly(poly(ethylene glycol) methyl ether methacrylate)-block-poly(2-(dimethylamino ethyl methacrylate)-block- poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMA–b–PDMAEMA–b–PPEGMA) triblock copolymer was synthesized by subsequent atom...
The self-condensing vinyl polymerization system consisting of inimers and multifunctional core initiators is studied by the principle of statistical mechanics. From viewpoints of functional groups and polymers, two types of canonical partition functions are constructed and further are proved to be consistent with each other. In this way, the explicit expressions of equilibrium free energy and law...
Chain walking ethylene copolymerizations with cyclopentene (CPE) as the ring-forming comonomer were carried out in this study to investigate the tuning of polyethylene chain topology via the unique strategy of ring incorporation. Four sets of polymers containing five-membered rings on the polymer backbone at various low contents (in the range of 0–7.5mol%) were synthesized by controlling CPE feed...
Biodegradable polymer vesicle for drug delivery is reported. Poly(ɛ-caprolactone)-block-poly(ethyl ethylene phosphate) with well-defined structure (PCL 150 -b-PEEP 30 ) has been prepared by ring-opening polymerization. It forms vesicles in aqueous solution using the thin-film hydration method and further exclusion of the as-formed vesicles results in vesicles at nano-size, demonstrated...
A series of novel 4-arm biodegradable star block copolymers of poly(ɛ-caprolactone) and poly(ethyl ethylene phosphate) were synthesized via ring-opening polymerization of 2-ethoxy-2-oxo-1,3,2-dioxaphospholane using hydroxyl terminated 4-arm star-shaped poly(ɛ-caprolactone) and stannous octoate co-initiation system. Gel permeation chromatography (GPC), NMR and FT-IR were used to demonstrate the structure...
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