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Samples of linear polyethylene, neat and crosslinked by irradiation with electron beam, were subjected to heavy plastic deformation by plane-strain compression up to the true strain exceeding 2 (deformation ratio λ > 8) at room temperature. Structural studies of deformed samples and investigation of long-term strain recovery demonstrated that the deformation of the neat, non-crosslinked HDPE is...
In-situ polymerization of thermoplastic polyurethane (TPU) and carbon nanotubes (CNTs) is one of the best methods to obtain nanocomposites with well dispersed nanofillers and superior properties. The effect of nanofillers on reaction is an important factor during in-situ nanocomposite preparation. TPU/CNT nanocomposites were prepared via a sustainable in-situ polymerization of Polycaprolactonediol...
Poly(lactic acid) (PLA) films were immersed in pure water, 50% and 95% ethanol solutions for up to 180 days. The change in molecular weight, sorption of water, sorption of ethanol, and lactic acid released were monitored. Glass transition temperature and percent crystallinity as a function of ethanol content were also measured. PLA experienced faster hydrolytic degradation in contact with 50% than...
The cationic polymerization of isobutylene using pre-activated by the wet argon or salts hydrates iBuAlCl2 as catalyst in the presence of diisopropyl ether in n-hexane at 10 °C as a starting temperature and high monomer concentration ([IB] = 5.8 M) has been investigated. It was shown that pre-activated iBuAlCl2 possessed high activity (>90% of monomer conversion in 10 min) and unexpectedly high...
This work focuses, for the first time, on the structural evolution of Polylactide (PLA) and PLA-Talc nanocomposites upon biaxial stretching. Biaxial stretching is a widely used technique to improve the end-use properties of polymer films. Encountered in a large number of elaboration processes it involves important structural changes into the material which directly govern the properties gain. In this...
Polymer field-effect transistors (PFETs) are promising candidates for future electronics due to easy and inexpensive fabrication. Poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene) [P(NDI2OD-T2)] based PFET devices with poly (methyl 2-methylpropenoate) (PMMA) as dielectric were fabricated successfully and it was found that the charge transporting...
This work focuses on the mechanical behavior and the associated structural evolution of Polylactides homopolymers blends, i.e. PLLA and PDLA blends, with the aim of determining the ability to form the sterecomplex crystalline form upon stretching. The investigations carried out on initially amorphous samples revealed that only the crystalline α′-form, i.e. the one encountered in the case of the homopolymers,...
In this study, the solution structure of sacran, cyanobacterial polysaccharide, was estimated by synchrotron X-ray scattering. The chain conformation of sacran in solvent significantly differs depending on the concentration even though it has extraordinary stiffness (109 nm of persistent length). The sacran assemblies under concentrated conditions exhibited hierarchical structure (i.e., macroscopic...
In the present work, poly(vinyl acetate) grafted cellulose nanocrystals (CNC-g-PVAc) were prepared via surface initiated reversible addition-fragmentation chain transfer and macromolecular design via the interchange of xanthates (SI-RAFT/MADIX) polymerization. Successful grafting of PVAc from CNC was confirmed by FT-IR and TGA analysis. PVAc nanocomposites reinforced with CNC-g-PVAc, as well as pristine...
Two donor polymers containing thiophene (T) and thienothiophene (TT) as the electron rich, and diketopyrrolopyrrole (DPP) as the electron poor, moieties were synthesized and utilized in organic photovoltaic (OPV) devices. We appended n-decyl side chains onto the thiophenes directly adjacent to the di-hexyldecyl substituted DPP center core to ensure solubility of the resulting polymers. We observed...
The effects of polydispersity, additives, impurities, free top layer and of surface roughness on the nucleation are studied for poly(ethylene oxide) located inside self-ordered nanoporous aluminum oxide (AAO). AAO pore diameters ranged from 400 nm to 25 nm. With the exception of a surface layer, none of the above factors is able to induce heterogeneous nucleation under confinement. Homogeneous nucleation...
Delayed onset formulations for the peroxide-initiated crosslinking of a range of commodity polymers are described. 4-Acryloyloxy-2,2,6,6,-tetramethylpiperidin-N-oxyl (AOTEMPO) is effective for controlling the crosslinking dynamics and yields of linear low density polyethylene (LLDPE), poly(ethylene-co-vinyl acetate) (EVA), poly(ethylene-co-propylene) (EPR), and poly(ethylene-co-propylene-co-ethylidenenorbornadiene)...
A simple and low-cost process has been demonstrated for the fabrication of high-performance light diffuser films. Instead of polymer composites with light diffusing micro/nanoparticles as in typical approaches, low refractive-index (RI) air pockets or pores have been included inside the diffuser film, which has large RI contrast to host polymer matrix. The generation of such pores has been enabled...
Hydrogen (H)-bonding interaction was introduced into a poly(ethylene oxide)-b-poly(tert-butyl acrylate) (PEO-b-PtBA) block copolymer (BCP) by partial hydrolysis of tBA units into acrylic acid (AA) ones, in order to compete with the segregation force between the PEO and PtBA blocks. It was found that, as the hydrolysis degree (Dhyd) of the PtBA block increased, the structure of the PEO-b-P(tBA-co-AA)...
Polymeric materials with alternating multi-layer structure have gained much attention in the field of biomimic, where many methods were used to prepare materials with such structure for various functionalities. A simple method based on high speed thin-wall injection molding (HSTWIM) has been proposed in our previous studies for the easy fabrication of multi-layer functional polymeric materials. Herein,...
In this article, we report preparation and studies of water dispersible polyurethane (WDPU) nanocomposite which has high hydrophobic characteristics with contact angle greater than 100° and strong thermo-mechanical properties. An in-situ method is developed for synthesizing the WDPU nanocomposites where hydroxyl terminated polybutadiene (HTPB) functionalized at the terminal carbon atoms with dinitrobenzene...
We present a new and facile strategy for the fabrication of conducting honeycomb-patterned porous films through interfacial polymerization. Polymer solutions containing poly(ε-carprolactone) (PCL) and benzoyl peroxide (BPO) in chloroform was fabricated under high humid conditions to obtain PCL-BPO honeycomb patterned films. The films were treated with aqueous aniline hydrochloride solution to polymerize...
We report, for the first time, a nanoscale control of the spatial distribution of semiconducting tetrapod (TP) nanocrystals within block copolymer particles. Polystyrene (PS) block copolymer (BCP)/CdSe TP nanocrystal hybrid particles were prepared by the nanoprecipitation of TP/BCP mixtures into methanol. The BCPs consisted of short, polar terminal block bearing methyl disulfide anchoring moiety which...
Though 4,4′-methylene diphenyl diisocyanate (4,4′-MDI) is a key monomer in polyurethane synthesis, its infrared spectrum has not been discovered and assigned to the molecular vibrations in detail yet. To close that impedimental analytical gap, the conformers of 4,4′-MDI and their vibrational properties are explored by DFT calculations and accurate IR band assignment is achieved for the first time...
We report the remarkable effect of a small amount of poly(2-dimethyl amino ethyl methacrylate) (PDMA) or PDMA-b-poly(N-isopropyl acrylamide) copolymer on the composition and the sol fraction of amphiphilic co-network (APCN) gels formed by the sequential nucleophilic substitution reaction between activated halide terminated polycaprolactone (PCL) and tertiary amine functional agarose or dextran. PDMA...
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