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Miniemulsion reversible addition-fragmentation chain transfer (RAFT) polymerization was used to synthesize biomimetic poly (2-methacryloyloxyethyl phosphorylcholine)-b-Poly (n-butyl methacrylate) (PMPC-b-PBMA) nanoparticles which were used as nanocarriers to encapsulate theranostic IR-780 molecules. IR-780 endowed the PMPC-b-PBMA nanoparticles with dual functions including tumor near-infrared (NIR)...
Deformation of amorphous, glassy polycarbonate (PC) is characterised over a wide range of length-scales using spatially-resolved wide angle X-ray scattering (WAXS) with simultaneous digital image correlation and in-situ uni-axial loading. Novel observations are presented on the correlation of the evolution of the molecular structure linked to the relevant local macroscopic measures of strain as the...
Development of a methodology for designing network polymers with both structural rigidity and facile degradability is an important challenge. In this paper, we demonstrate the efficient degradation of epoxy resins with disulfide linkages synthesized from bis(4-glycidyloxyphenyl)disulfide and several diamines. The synthesis was carried out without any undesired side-reactions derived from disulfide...
Diglycidyl ethers of bisphenol-A (DGEBA)/4,4′-diaminodiphenylmethane (DDM)/polyethersulphone (PES) blends were prepared as matrix resins for electrically conductive adhesives containing silver (Ag) fillers. The epoxy/PES blends formed co-continuous phase structures from initial homogeneous solutions via reaction-induced phase separation during the curing process. The Ag fillers were selectively localized...
The investigation of the molecular mobility of polymer chains and networks in the presence of active fillers such as carbon black or silica presents a big interest for the physics of reinforced rubbers. A better understanding of the physical characteristics of the filler–rubber interface is necessary to improve the overall macroscopic properties of these elastomers. The main goal of our work is to...
This article features recent studies on Pd-catalyzed isomerization polymerization of dienes, cyclopentenes and alkenylcyclohexanes. Pd complexes with diimine ligands promote controlled cyclopolymerization of functionalized 1,6-dienes to afford the polymers with repeating trans-1,2-bis(methylene)cyclopentylene units. The dienes copolymerize with various olefins, such as ethylene, α-olefin, and cyclopentene,...
The manufacturing of polytetrafluoroethylene products is usually carried out by cold isostatic and/or uniaxial pressing of the powdered polymer, followed by sintering of the “green” parts. During pressing, the air initially present in the loose powder leads to the formation of defects in the material, but the mechanisms involved are not entirely understood. The aim of this study was to better understand...
Cross-linking co-polymerization was studied in the presence of di-, tri- or tetra-functional cross-linkers using the Bond Fluctuation Model (BFM). Network formation was analyzed for varying cross-linker reaction rates, cross-linker composition and number fraction, cross-linker functionality and time dependent initiator release. Additionally, the effect of inhomogeneous radical release and radical...
This article concerns preferential orientations of the crystal a-axis for the standard type PBO AS and high modulus type HM fibers. The degree of radial preferential orientation of the crystal a-axis along the fiber radius direction was analyzed based on a newly-proposed 3D two-phase model. The result was compared with the previously analyzed three PBO fibers made through water vapor, hot water and...
We demonstrate selective dispersion of photosensitive electron acceptor phenyl-C61-butyric acid methyl ester (PCBM) in cylinder forming polystyrene-b-poly (ethylene oxide) (PS-b-PEO) block copolymer (BCP). Neat PS-b-PEO is structurally robust to forming vertically oriented nanoscale morphology of PEO cylinders in the PS matrix directly after solvent casting. Varying amounts of PCBM nanoparticles were...
An expanded triptycene (hexaphenylbenzene based triptycene) monomer was synthesized from triiodotriptycene. Using this monomer, two kinds of organic microporous polymers HTPs (HTP-A and HTP-B) were prepared by Friedel–Crafts and Scholl reactions. Their structure and properties were characterized by FT-IR, solid 13C NMR, powder XRD, SEM, TEM and gas absorption. Nitrogen sorption analysis displayed...
We used differential scanning calorimetry (DSC) to study the effect of confinement on the glass transition temperature (Tg) of poly(methyl methacrylate) (PMMA) nanotubes supported in anodic aluminum oxide (AAO) templates. We created nanotubes by wetting templates with polymer melts and developed a design equation relating tube thickness (ttube) with bulk radius of gyration (Rg): (ttube ≈ 2 Rg + 9 nm)...
The present work explores synthesis of a nano-porous network of DMTD-Ag coordination polymer derived from 2,5-Dimercapto-1,3,4-thiadiazole (DMTD) and AgNO3. This network of DMTD-Ag is thoroughly investigated using FT-IR, Raman, XPS, SEM, TEM and TGA. After that a successful application of DMTD-Ag for the electrochemical assay of atropine sulphate using differential pulse voltammetry (DPV) technique,...
A heterobifunctional monomer, namely, 3-(4-ethenylphenyl)-3,4-dihydro-2H-1,3-benzoxazine (VBOZN), which contains both vinyl group and benzoxazine group, was successfully prepared by three-step method with high purity and satisfactory yield. The chemical structure of VBOZN was identified by NMR, FTIR and elemental analysis. VBOZN selectively underwent free radical polymerization initiated by azodiisobutyronitrile...
Continuous fibrous composite tapes of polyamide 6 (PA6)/polyethylene oxide (PEO) containing over 16 thousand individual ribbon-like PA6 micro-/nano-fiber domains were produced using a novel co-extrusion and two-dimensional multiplication technique. This melt-based process is suitable for scaling-up, applicable to any melt-processable polymers, and highly adjustable in terms of material composition,...
Digital image correlation techniques were applied to compressive strain recovery experiments of glassy network isomers to study architectural contributions to deformational response. Strain recovery experiments provided a direct comparison of network isomer structure on viscoelastic deformation. Diglycidyl ether of bisphenol-A (DGEBA) was cured with 3,3′- and 4,4′-diaminodiphenyl sulfone (33DDS and...
PolyHIPEs are porous polymers synthesized within high internal phase emulsions (HIPEs). This paper describes hydrogel-filled, shape-memory polyHIPEs (SMPHs) based upon a polyacrylate with crystallizable side-chains. These polyHIPEs had closed-cell-like voids with diameters ranging from 5 to 100 μm and a 200 nm thick hydrogel coating. The mechanical behavior was determined by the temperature and by...
Crystallization from melt of poly(vinylidene fluoride) was studied by thin film chip calorimetry at cooling rates from 500 to 100,000 Ks−1 and isothermally down to 76 °C. At ca. 70 °C, for cooling rates higher than 2000 Ks−1, there appears a change in crystallization from high temperature α phase to low temperature β phase. The amorphous state is preserved at cooling rate 100,000 Ks−1. Analysis of...
Polydopamine (PDA) was spontaneously coated on acid treated MWCNT or pristine MWCNT surface via oxidative polymerization. The effect of PDA modified MWCNT hybrids on the lap shear strength of epoxy/aluminum joints and the failure mechanisms were systematically investigated. The PDA/acid modified MWCNT hybrid at only 0.5 wt% led to a substantial increase in the lap shear strength in comparison to neat...
Filler–filler and filler–matrix interactions in polymer composites increase with filler concentration and strongly influence the mechanical and rheological properties of polymer composites. By means of the spouted bed spray granulation process polymer composites with an extremely high concentration of inorganic fillers can be prepared. In this work, the viscoelastic properties of highly filled composites...
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