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Organo-modification of montmorillonite (MMT) is crucial for the promotion of a fine dispersion of MMT into an (often hydrophobic) polymer matrix. Ammonium-terminated polymers are more efficient in modifying clay compared to small organic cations such as alkyl ammoniums or side functionalized polymers. Herein, tri-amino end functional polyethylene (PE-3 N) with low molecular weight was first synthesized via an efficient and robust epoxide ring-opening reaction by treating epoxide-terminated PE with diethylenetriamine. The chemical structure of PE-3 N was unambitiously characterized by chromatographic and spectral methods. By reacting with excess HCl, PE-3 N was subsequently converted to tri-ammonium end functional polyethylene (PE-3 N+), which serves as an intercalation agent of MMT. By adjusting the weight ratio of PE-3 N+ to pristine MMT ( RP/M) applied in the static melt intercalation process, correlations between the extent of exfoliation and RP/M were successfully established. XRD results revealed that complete exfoliation of MMT could be afforded with RP/M as low as 1, which is the lowest value ever reported for ammonium-terminated polymers applied as intercalation agents. SEM micrographs showed that MMT sheets were swollen by PE-3 N+, affirming the successful modification of MMT. The PE modified MMT obtained may find application in preparing high-performance PE/MMT nanocomposites. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A new synthetic procedure is described for the preparation of dendritic polyethylene brushes with polysiloxane as the main chain, describing for the first time that it is possible to simply and efficiently prepare highly branched architectures for this type of polymer. Furthermore, as a result of the polymer brush architecture, polyethylene acts as the side chains and Si-O-Si as the backbone. The number average molecular weight (Mn) of the polyethylene brushes, which is determined using a multiple angle laser light scattering detector, increases from 5946 to 27 684 g mol-1 while retaining relatively narrow polydispersities (1.5-2.4). The polymer brushes are characterized by solid 29Si NMR and high-temperature ¹H NMR spectra. In addition, X-ray photoelectron spectroscopy and gel permeation chromatography were used to confirm the structure. [ABSTRACT FROM AUTHOR]

Hyperbranched poly(glycidol) (HPG) containing hydroxyl groups is firstly synthesized via anionic polymerization, and then reacts with thionyl chloride to form chlorine end-terminated hyperbranched poly(glycidol) (HPG-Cl). Different ionic liquid polymers are synthesized from the reaction of HPG-Cl with N-methylimidazole and then anion exchange with hexafluorophosphoric acid and sodium tetrafluoroborate. The structure and properties of the obtained ionic liquid polymers are characterized by H NMR, ATR-FTIR, DSC and TGA, respectively. Ionic conductivity of the polymer electrolytes composed of ionic liquid polymer and lithium bis(trifluoromethanesulfonimide) (LITFSI) is investigated by electrochemical impedance spectroscopy. The results show that the ionic conductivity of the prepared ionic liquid polymer electrolyte can reach 3.5 × 10 Scm at 30 °C when the weight ratio of ionic liquid polymer ([HPG-MeIm]BF) to lithium salt (LiTFSI) is 4.5. [ABSTRACT FROM AUTHOR]

Polyethylene based polyurethanes (PE-PUs) with 20% ethyl branches were synthesized through hydrogenation reaction of linear and thermoplastic hydroxyl-terminated polybutadiene based polyurethanes (HTPB-PUs), which has not been explored widely. Linear and thermoplastic HTPB-PUs with Mw ranged from 130~280 kg/mol were synthesized by microwave-assisted reaction. More importantly, we systematically researched a series of reaction conditions to ensure the degree of hydrogenation meanwhile slow down the extent of degradation reaction of urethane bond. In addition, structure and thermal performance of PE-PUs have been investigated in the present work by NMR, FT-IR, DSC and TGA. The Mw of PE-PUs ranging from 120~207 kg/mol were carried out with a high temperature GPC. Moreover, the degree of crystalline of PE-PUs with 20% ethyl branches at the range of 10% to 33% were further explored by X-ray diffraction, which in turn certify that the PE-PUs possess certain strength but lower than polyethylene with no branches. [ABSTRACT FROM AUTHOR]