Synthesis and characterization of novel hybrid polyoxazoline‐grafted multiwalled carbon nanotubes

The novel hybrid polyoxazoline‐grafted multiwalled carbon nanotubes (POZO‐grafted MWNTs) were synthesized by the reaction of partially hydrolyzed polyoxazolines (Hydrolyzed‐POZO) and MWNTs having carboxylic acid groups (MWNT‐COOH) in the presence of DCC as a condensing agent. Hydrolyzed‐POZO (degree of hydrolysis, 20.2 mol % by ¹H‐NMR) were produced from the hydrolysis of polyoxazolines in an aqueous NaOH solution at reflux for 72 h. MWNT‐COOH were prepared by acid treatment of pristine MWNTs. The composition, structure, thermal property, and surface morphology of the novel hybrid POZO‐grafted MWNTs were fully characterized by FT‐IR, Raman, ¹H‐NMR, DSC, TGA, SEM, and TEM. The obtained POZO‐grafted MWNTs are well soluble in various organic solvents and water. It was observed that the glass transition temperature (T_g) of POZO‐grafted MWNTs was lower than that of Hydrolyzed‐POZO due to the absence of hydrogen bonding interactions between Hydrolyzed‐POZO itself caused by the incorporation with MWNTs. It was also found that Hydrolyzed‐POZO was homogeneously attached to the surfaces of MWNTs through the “grafting‐to” method. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Polyoxazoline associated with cardanol for bio‐based linear alkyl benzene surfactants

Well‐defined linear alkyl benzene surfactants (COx_n) were successfully synthesized using cardanol as a green phenolic alternative and initiator for polyoxazoline (POx), the hydrophilic block of nonionic surfactants. Various hydrophilic lipophilic balance values were investigated by varying the POx length according to the [monomer]/[initiator] ratio. The chemical structure of the surfactants, in particular the terminal groups, was well identified by matrix assisted laser desorption ionization time of flight mass spectrometry demonstrating the good progress of the cationic ring‐opening polymerization. The COx_n surfactants spontaneously self‐assembled in water at a critical aggregation concentration of 1–2 µmol L^?1 into nano‐objects characterized by a hydrodynamic diameter of 11–24 nm and a number of aggregations ranging from 30 to 60 according to the worm‐like micelle model. © 2019 Society of Chemical Industry     

Telechelic polymers by living and controlled/living polymerization methods

Telechelic polymers, defined as macromolecules that contain two reactive end groups, are used as cross-linkers, chain extenders, and important building blocks for various macromolecular structures, including block and graft copolymers, star, hyperbranched or dendritic polymers. This review article describes the general techniques for the preparation of telechelic polymers by living and controlled/living polymerization methods; namely atom transfer radical polymerization, nitroxide mediated radical polymerization, reversible addition-fragmentation chain transfer polymerization, iniferters, iodine transfer polymerization, cobalt mediated radical polymerization, organotellurium-, organostibine-, organobismuthine-mediated living radical polymerization, living anionic polymerization, living cationic polymerization, and ring opening metathesis polymerization. The efficient click reactions for the synthesis of telechelic polymers are also presented.     

Functionalization of lignin: Synthesis of lignophenol‐graft‐poly(2‐ethyl‐2‐oxazoline) and its application to polymer blends with commodity polymers

Lignophenol (LP)‐graft‐poly(2‐ethyl‐2‐oxazoline) (POZO) was prepared to reuse lignin, an industrial waste material, and to produce novel LP‐based polymer blends with poly(vinyl chloride) (PVC), poly(bisphenol A carbonate) (PC), polyvinylpyrrolidone (PVP), and polystyrene (PSt) as commodity polymers. The resulting graft polymer was soluble in various types of organic solvents such as chloroform, THF, acetone, and methanol, unlike LP. The miscibility of LP‐graft‐POZO with commodity polymers was measured by differential scanning calorimetry (DSC) to determine the glass transition temperatures (T_g). In the cases of the blends of LP‐graft‐POZO with PVC, PC, and PVP, the T_g values decreased during the second scan. Moreover, in the cases of the blends with PVC and PVP, the T_g values were not detected during the third scan. Therefore, it was inferred that LP‐graft‐POZO was miscible with PVC, PC, and PVP while forming single phases; in particular, the blends of LP‐graft‐POZO with PVC and PVP exhibited a secondary miscibility because the T_g values were not detected. Furthermore, the blend of LP‐graft‐POZO with PC exhibited better thermostability than LP and LP‐graft‐POZO. These results indicated that LP blended with POZO could be used as a polymer additive and as an adhesive to combine different polymers, organic–inorganic polymers, etc. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012