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Poly(aniline-co-o-bromoaniline) (p(an-co-o-BrAn)) copolymer has been synthesized using chemical oxidation method in the hydrochloric acid medium. Copolymerization of aniline with o-bromoaniline of different compositions, such as 1:1, 1:2, 2:1, 1:3 and 3:1 molar ratios were prepared. The synthesized copolymer is soluble in polar solvents like dimethyl sulphoxide (DMSO), dimethyl formamide (DMF), Tetrahydrofuran (THF) and 1-methyl 2-pyrrolidone (NMP). The copolymer is analyzed by various characterization techniques, such as FTIR, UV–Visible (UV–Vis) spectroscopy, X-ray diffraction (XRD), conductivity, Differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). FTIR spectrum confirms the characteristic peaks of the copolymer containing benzenoid and quinoid ring stretching. UV spectrum reveals the formation of $\pi$–${\pi }^{\ast }$ transition and $n$–${\pi }^{\ast }$ transition between the energy levels. XRD peaks reveal that the copolymer possesses amorphous nature. Morphological study reveals that the agglomerated particles form globular structure and size of the each particle is about 100 nm. The electrical conductivity of the copolymers is found in the range of $10^{-5}\mathrm{\text{S}}{\mathrm{\text{cm}}}^{-1}$. These organic semiconductor materials can be used to fabricate thinner and cheaper environmental friendly optoelectronic devices that will replace the conventional inorganic semiconductors.

The nonlinear optical properties of a nanoparticle polyaniline/polyacrylonitrile (PAn/PANr) copolymer newly prepared via experimental and theoretical findings are reported. Diffraction ring patterns result in the far field when a CW, visible, 473 nm, low power laser beam traverses the solution of PAn/PANr in the solvent ethanol. The diffraction ring patterns are usually used to estimate the nonlinear refractive index while the Z-scan is used to measure both nonlinear refractive index and its sign and nonlinear absorption coefficient. The experimentally observed ring patterns are numerically reproduced via the use of the Fresnel–Kirchhoff procedure. Good agreement between experimental findings and the numerical ones are obtained. The obtained diffraction ring patterns suffer modification in the vertical direction due to convection current as a result of local heating of the sample and the presence of gravity.

In this study, electrorheological (ER) properties of biodegradable and conducting polyaniline-graft-chitosan (PAni-g-CS) copolymer particles were investigated. For this purpose, PAni and PAni-g-CS particles were synthesized by using in situ oxidative radicalic polymerization method. At first, PAni and PAni-g-CS/silicone oil (SO) ER suspensions (15% V/V) were subjected to external electric field and they exhibited low ER activity. When the external electric field strengths ($E)$ were increased, both the suspensions showed electrical breakdown. Therefore, virgin PAni and PAni-g-CS were first subjected to dedoping process by treating with 1.0 M NaOH(aq) and non-ionic surfactant Triton X-100 (T-X) surfactant to enhance the expected ER activity and prevent the electrical breakdown. But we observed that the addition of T-X as promoter had no significant effect on the ER activity. On the other hand, electric filed-induced viscosities of both the suspensions were observed to enhance after the dedoping (DD) process and electrical breakdown prohibited. After the DD process, DD PAni-g-CS/SO ER system exhibited the highest electric field-induced viscosity by reaching 400Pa⋅s at $E=4$kV/mm. The highest ER efficiency was also obtained for DD PAni-g-CS/SO system at 15% (V/V) as 79. Additionally, typical shear thinning non-Newtonian viscoelastic behavior was observed under externally applied E. The conduction model of DD PAni-g-CS/SO system was determined to well fit the conduction model by showing a slope of $m=1.5$ calculated from the E vb. yield stress graph. In conclusion, conducting and biodegradable-dedoped PAni-g-CS particles would be a good candidate for potential ER applications as dry-based ER materials having high colloidal stability of 76%.

This paper describes a simple and economic approach for fabrication of surface wettability gradient on poly(butyl acrylate – methyl methacrylate) [P (BA–MMA)] and poly(butyl acrylate – methyl methacrylate – 2-hydroxyethyl methacrylate) [P (BA–MMA–HEMA)] films. The (meth)acrylate copolymer [including P (BA–MMA) and P (BA–MMA–HEMA)] films are hydrolyzed in an aqueous solution of NaOH and the transformation of surface chemical composition is achieved by hydrolysis in NaOH solution. The gradient wetting properties are generated based on different functional groups on the P (BA–MMA) and P (BA–MMA–HEMA) films. The effects of both the surface chemical and surface topography on wetting of the (meth)acrylate copolymer film are discussed. Surface chemical composition along the materials length is determined by XPS, and surface topography properties of the obtained gradient surfaces are analyzed by FESEM and AFM. Water contact angle system (WCAs) results show that the P (BA–MMA–HEMA) films provide a larger slope of the gradient wetting than P (BA–MMA). Moreover, this work demonstrates that the gradient concentration of chemical composition on the poly(meth) acrylate films is owing to the hydrolysis processes of ester group, and the hydrolysis reactions that have negligible influence on the surface morphology of the poly(meth) acrylate films coated on the glass slide. The gradient wettability surfaces may find broad applications in the field of polymer coating due to the compatibility of (meth) acrylate polymer.

A series of random copolymers of 2,7-dibromo-9,9-bis(4′-n-octyloxyphenyl) fluorene (BOPF) and 2,7-dibromo-N-(2′-ethylhexyl)carbazole (EHC) were synthesized through Ni(0)-mediated polymerization. Carbazole comonomer was introduced to improve the hole-transporting properties of PBOPF. The synthesized poly(BOPF-co-EHC)s showed similar UV-visible absorption and PL emission to PBOPF. EL devices were fabricated in an ITO/PEDOT/polymer/Ca/Al configuration. EL devices which used copolymers showed improved device performance over devices which used PBOPF homopolymers due to a more balanced charge transport.

The hydrogen bonding interactions between letrozole (Let) anticancer drug and three copolymers of methacrylic acid-trimethylolpropane trimethacrylate (M1–M3 as molecular imprinted polymers) were studied using density functional theory (DFT) at both B3LYP and B3PW91 levels. The binding energies were corrected for the basis set superposition error (BSSE) and zero-point vibrational energies (ZPVE) so that the most negative $\mathrm{\Delta }{E}_{\mathrm{\text{binding}}}$ were measured for compounds 7 and 8 formed between M1 copolymer and endocyclic N1 and N2 atoms of drug, respectively. Also, among complexes 13–15 in which two copolymers were contributed in the formation of O–H$\dots$N bonds with the drug, compound 13 (containing two M1 copolymers) showed the highest $\mathrm{\Delta }{E}_{\mathrm{\text{binding}}}$ value. The interactions of all copolymers with drug were exergonic (spontaneous interaction) and exothermic. The QTAIM data supported the covalent character of the C–N, C–H, N–N, C–O, O–H and O–H$\dots$N bonds, the intermediate nature of C$\equiv$N and C$=$O bonds while the electrostatic character of C–H$\dots$O, HC$\dots$HC and CH$\dots$N interactions. According to the $\mathrm{\Delta }{E}_{\mathrm{\text{binding}}}$, $\mathrm{\Delta }{G}_{\mathrm{\text{interaction}}}$ and $\mathrm{\Delta }{H}_{\mathrm{\text{interaction}}}$ values, it was suggested that t complexes 7 and 8 (among two particles systems) as well as complex 13 (among three particles systems) can be the most promising drug delivery systems.

Melt extrusion was used to prepare binary nanocomposites of ethylene copolymers and organoclay and trinary nanocomposites of low-density polyethylene (LDPE), ethylene copolymer and organoclay. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to analyze the structure of the clay phase and the morphology of the nanocomposites. Influences of the comonomer in the copolymer and the content of the copolymer on the morphology of the resulting nanocomposites were discussed. The binary and the trinary composites may form intercalated or exfoliated structures depending on the interaction between the copolymer and the clay layers and the content of the copolymer.

Poly(amino acid) has been widely utilized in drug delivery, tissue engineering and biomedical materials. The biomaterials based on poly(glutamic acid) are usually modified via copolymerization with other monomers such as L-aspartic acid to improve the uncontrolled degradation rate. The ring-opening homo- and co-polymerization of γ-benzyl-L-glutamate N-carboxyanhydride (BLG-NCA) and β-benzyl-L-aspartate N-carboxyanhydride (BLA-NCA) were carried out in solution by using triethylamine (TEA) as initiator. The BLG-NCA homopolymerization could take place even at -30°C and molecular weight of poly(γ-benzyl-L-glutamate) decreased with increasing polymerization temperature. The BLA-NCA polymerization did not occur at -10°C and was needed to be carried out at 25°C to improve the polymerization. Poly(γ-benzyl-L-glutamate) and poly(β-benzyl-L-aspartate) with unimodal molecular weigh distribution and weight average molecular weight (M_w) of 32100 and 4000 could be obtained at 25°C. The copolymers of γ-benzyl L-glutamate and β-benzyl L-aspartate with unimodal molecular weight distribution and M_w ranging from 5600 to 24600 could be prepared. The useful copolymers of poly(L-glutamic acid-co-L-aspartic acid) were further prepared by removal of benzyl groups.

The methyl methacrylate (MMA)/1-propylmethacrylate-polyhedral oligomeric silsesquioxane (PM-POSS) copolymers were synthesized via atom transfer radical polymerization with CuBr as catalyst. The unreacted PM-POSS monomer could be removed completely by washing the copolymerization product with n-hexane. The copolymers were characterized with ¹H-NMR, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis and gel permeation chromatography. With increasing PM-POSS feed ratio, the total conversion increased while the glass transition temperatures of copolymer decreased. The thermogravimetric analysis demonstrated that the thermal stability of copolymer improved slightly with PM-POSS addition. The molecular weight of copolymers increased with incorporation of PM-POSS.

The methods for the synthesis of porphyrins containing active vinyl groups on a periphery of the tetrapyrrole macroheterocycle are described. The possibility of their usage as comonomers in a copolymerization reaction with methyl methacrylate is given.

Serving as platforms for both cellular interrogation as well as biomembrane mimicry, biotic–abiotic functionalized materials, such as block copolymeric membranes, offer the opportunity for tailored biology, where specific embedded functionalities can be rapidly engineered, on demand, without the need for genetic processing. These versatile materials enable rapid, thin film deposition of a plethora of biologically-relevant materials at the air–water interface given their amphiphilic properties, meaning that they possess alternating hydrophilic and hydrophobic components. This property confers to these materials the ability to be transferred to a wide range of substrates and materials, further enhancing their interfacial versatility. In addition, their biologically-inert, and tunable, thickness-dependent insulating properties serve as ideal bio-active substrates while maintaining the functionality of the integrated molecule (e.g., protein, effector molecule, etc.). Here, we report the application of a polyethyleneoxide–polymethylmethacrylate (PEO–PMMA) diblock and polymethyloxazoline–polydimethylsiloxane–polymethyloxazoline (PMOXA–PDMS–PMOXA) triblock copolymers as molecular anchors for tethering a broad spectrum of materials. These include carbon nanotubes for the fabrication of bioelectrodes to measure cytochrome c-mediated oxidation-reduction, as well as the anti-inflammatory molecule, dexamethasone, for the suppression of lipopolysaccharide (LPS)-induced inflammation in murine macrophages. As such, this work demonstrates the versatility, and broad applicability and impact of this platform approach towards the fabrication of multifunctional arrays of biologically-active surfaces for experimentation ranging from bio-electroactivity to studies of cellular immunity.

Copolymer based on triphenylamine (TPA) and 3,4-ethylenedioxythiophene (EDOT) is polymerized electrochemically. The structure, morphology and electrochemical properties of the obtained copolymer are investigated by cyclic voltammetry and FT-IR spectroscopy. The results confirm the copolymerization of TPA/EDOT. UV-vis spectra show that the absorption peaks of the copolymer are different from those of Polytriphenylamine. Moreover, photoluminescence spectra of the copolymer exhibit great changes in emission color from pale blue to pale green with the variety of ratio of two monomers. Therefore, the monomer feed ratio plays important roles in the optical property of this copolymer.

A resistive memory device using butyl methacrylate (BMA)/N, N' -4, 4'-diphenylmethane-bismaleimide (BMI) copolymer as the active layer and Al as electrodes exhibited excellent dynamic random access memory (DRAM) characteristics. The copolymer was synthesized with BMA and BMI monomer by the conventional free radical polymerization. The fabricated Al/BMA-BMI copolymer/Al matrix structure memory device demonstrates high ON/OFF-current ratio of about 10⁴, superior stability under DC switching sweep without any degradation in current and any change in switching threshold voltage. In addition, low switching threshold voltage of about 2.6V and low OFF-current of about 10^-4 mA were observed during the test.

This experiment evaluates the softwood bleached chemi-mechanical pulp that was treated twice using a graft copolymer prepared by the new super oil-absorbing material. Due to the use of natural fiber materials, the oil-absorbing material prepared are easy to break down, not on the environment disadvantages caused by pollution. Experimental results showed that the optimal reaction conditions for the first time vaccination copolymer treated as KMnO₄ / H₂SO₄ amount of initiator was 0.08mmol / g. The methyl methacrylate (MMA) had an amount of 1.5g / g and a second graft copolymer dodecyl trimethyl ammonium bromide (CTAB) had an amount of 0.01g / g. When the reaction mixture and the copolymerization ratio of the two were inoculated 1: 100, the respective reaction at temperatures of 30℃, at 40℃, process conditions 2 hours, the treated slurry has the best performance of the suction oil absorption rate increased to 10.69 from the original 1.015.

A major source of our energy consumption is from oil, coal, natural gas and other fossil fuels, out of which, oil is the most popular. Unfortunately, due to human activities such as mining and extraction of oil (especially in the past 100 years), oil resources are running out. Therefore, interest in heavy oil resources has been increasing. However, due to the large viscosity of the heavy oil, it is difficult to drill and transport. In this paper, the preparation of the viscosity reducer has been discussed. Several different types of oilsoluble viscosity reducer for the viscous crude oil were prepared by using solution polymerization method and compared by their physical properties and viscosity reduction effect by Infrared (IR), thermogravimetric (TG) and other testing method. We found that the viscosity reduction effect of the octadecyl acrylate — styrene copolymer is the best and that the viscosity reducer prepared by different polymerization monomers has a certain viscosity reduction effect.

The Langmuir- Blodgett (LB) technique makes it possible to prepare a thin film with a controlled thickness at the molecular level and a well-defined molecular orientation. It has also been studied extensively for photolithography in which it cannot only overcome the weakness of spin-coat films where molecules are distributed randomly, but also be expected to improve the resolution and the sensitivity of the resist effectively. A series of novel copolymer p (AMAc- pIPPMa) has been prepared by reactions of 1H-imidazo [4,5- f] [1,10] phenanthrolin-2-yl)phenyl methacrylate (pIPPMa) and methacrylate (AMAc). They could be formed well-ordered Langmuir monolayer at air/water interface and transferred onto substrates to form Langmuir- Blodgett (LB) films. Preliminary studies of photopatterning of LB films were carried out and the positive patterns were obtained, where a resolution of 0.75μm could be drawn. It confirmed that LB films were a fine material as resist film for photolithography.