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A diamine containing pyridine ring, amide, and ether groups was prepared via two-step reactions from 6-chloronicotinoyl chloride. A novel polyimide was prepared from polycondensation of pyromellitic dianhydride with the diamine. In addition, nanoporous polyimide films were prepared from graft copolyimides. A thermally labile oligomer, poly(propylene glycol) (PPG), was incorporated into the polyimide backbone to obtain graft copolyimides that left voids into the polymer matrix through thermolysis of the labile PPG blocks. The properties of polyimide and nanofoams were compared. The dielectric constant of nanofoams was reduced, whereas their thermal stability and mechanical properties were almost maintained in comparison to the homopolyimide. C INSTRUMENTSMelting pointswere measured in capillaries on a Buchi apparatus (model Buchi 535). FT-IR spectra were recorded in the

Poly(methyl methacrylate) (PMMA)/poly(ethylene oxide) (PEO) (90/10) nanocomposites containing various amounts of graphene nanoplatelets were fabricated by solution method and then the effects of graphene concentration on morphology, thermal, mechanical, and electrical properties of the nanocomposites were investigated. Characterization by electron microscopy and X-ray diffraction of the nanocomposites showed a relatively good dispersion of graphene sheets in the polymer matrix. The results indicated that thermal stability, glass transition temperature, and mechanical properties of PMME/PEO blend improved by increasing graphene concentration. The electrical properties of polymer nanocomposites revealed a significant improvement with increasing the amount of graphene and the percolation threshold was about 3.33 wt% of graphene.

Iron oxide nanoparticle (IONPs) have become a subject of interest in various biomedical fields due to their magnetism and biocompatibility. They can be utilized as heat mediators in magnetic hyperthermia (MHT) or as contrast media in magnetic resonance imaging (MRI), and ultrasound (US). In addition, their high drug-loading capacity enabled them to be therapeutic agent transporters for malignancy treatment. Hence, smartening them allows for an intelligent controlled drug release (CDR) and targeted drug delivery (TDD). Smart magnetic nanoparticles (SMNPs) can overcome the impediments faced by classical chemo-treatment strategies, since they can be navigated and release drug via external or internal stimuli. Recently, they have been synchronized with other modalities, e.g., MRI, MHT, US, and for dual/multimodal theranostic applications in a single platform. Herein, we provide an overview of the attributes of MNPs for cancer theranostic application, fabrication procedures, surface coatings, targeting approaches, and recent advancement of SMNPs. Even though MNPs feature numerous privileges over chemotherapy agents, obstacles remain in clinical usage. This review in particular covers the clinical predicaments faced by SMNPs and future research scopes in the field of SMNPs for cancer theranostics.

Reaction of 6‐chloronicotinoyl chloride with p‐phenylene diamine resulted in preparation of a dichloro diamide compound. Subsequently, chloro displacement of this compound with 4‐amino phenoxy groups led to production of a new pyridine‐based ether diamine named as N,N′‐(1,4‐phenylene)bis(6‐(4‐aminophenoxy) nicotinamide). Novel polyimide was prepared through polycondensation reaction of the diamine with hexafluoroisopropylidene diphthalic anhydride (6‐FDA) via two‐step imidization method. In addition, new nanoporous polyimide films were produced through graft copolymerization of polyimide as the continuous phase with a thermally labile poly (propylene glycol) oligomer as the labile phase. The grafted copolymers were synthesized using reaction of the diamine and 6‐FDA in the presence of poly (propylene glycol) 2‐bromoacetate as thermally labile constituent via a poly(amic acid) precursor process. The labile block was decomposed via thermal treatment to release inert molecules that diffused out of the matrix to leave pores with diameters between 30 and 60 nm. The structures and properties of polyimide and polyimide nanofoams were characterized by different techniques including 1H‐NMR, FTIR, TGA, DMTA, SEM, TEM, dielectric constant, and tensile strength measurement. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

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