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Novel three biologically active itaconimido thiourea derivatives (DI, DII and DIII) were synthesized via reaction of N-[4-(isothiocyanatecarbonyl)phenyl] itaconimide with either aniline, p-toluidine or p- amino benzoic acid, respectively. The radical polymerization of DI, DII and DIII in dimethyl sulfoxide using azobisisobutyronitrile initiator was successfully performed to produce three polymers that were denoted as PI, PII and PIII, respectively. Their chemical structures were confirmed by elemental analyses, FTIR, 1H-NMR and mass spectra. They showed a high potency for growth inhibition of E. faecalis, S. epidermidis, E. coli, A. niger, C. neoformans and C. tropicalis. This is not only illustrated by their high inhibition zone diameters but also by their low minimum inhibitory concentrations. Some of them showed activities better than the reference drug Amphotericin B against all the tested fungi. DIII and PIII were safe on normal fibroblast cells of the lungs of the human (MRC-5 cells) through their evaluation using cytotoxic activity measurement. The thermal stability of PVC in the presence of DI–DIII and their polymers PI–PIII was evaluated. In comparison with DBLC, Cd–Ba–Zn stearate and n-OTM as reference stabilizers, DI–DIII and PI–PIII greatly stabilize PVC against thermal degradation. This is evidenced by increased initial decomposition temperatures and decreased weight losses at particular temperatures. It was found that the substituent group having an electron releasing nature that incorporated into DII and PII enhances their performance for PVC stabilization. DI–DIII and PI–PIII achieve a lower degree of discoloration and molecular weight alteration of PVC than the industrial stabilizers.

In this study, the free radical copolymerization of glycidyl methacrylate (GMA) and methyl methacrylate (MMA) was investigated for the first time by solution free radical copolymerization in toluene at 80 °C using azobisisobutyronitrile as an initiator. The 1H-NMR spectroscopy has been used for determining the copolymer composition. Monomer reactivity ratios (r values) were calculated by various linear least-square methods. According to the results, using the Kelen–Tudos (KT) and extended Kelen–Tudos (Ex KT) methods the r values were obtained as $$ r_{\text{G}} = 1.528 \pm 0.168 $$ , $$ r_{\text{M}} = 0.789 \pm 0.121 $$ , and $$ r_{\text{G}} = 1.577 \pm 0.186 $$ , $$ r_{\text{M}} = 0.783 \pm 0.129 $$ , respectively. The calculated monomer reactivity ratios showed the higher reactivity for GMA (rG) compared to MMA (rM). Furthermore, the findings demonstrated random or ideal behavior ( $$ r_{\text{G}} \cdot r_{\text{M}} \simeq 1 $$ ) for these copolymers. The monomers sequence distribution as probability of finding the multiple sequence distribution of the GMA and MMA units in copolymers was calculated and showed higher probabilities for GMA sequences. Thermogravimetric analysis of the copolymers had three degradation stages, and the main degradation occurred at third stage (340–456 °C) with 56% weight loss. Also, with regard to initial temperature of degradation and T50, the thermal stability was improved 62% and 2.3%, respectively, by increasing MMA content in copolymer. These studies could uncover the underlying GMA–MMA composition in copolymer, shedding light on the future design of top-performing applications such as UV printing ink and resin industry.

The article investigates the performance of polymers prepared from castor oil and dodecyl acrylate as biodegradable multifunctional additive in the formulation of eco-friendly lubricant. Homopolymer of castor oil and its copolymers with dodecyl acrylate (DA) at different percentage ratios (w/w) were synthesized using azobisisobutyronitrile (AIBN) as initiator without any solvent. The polymers were characterized by spectral techniques (FT-IR and NMR spectroscopy). The molecular weight of all the prepared polymers was determined by gel permeation chromatography (GPC). The thermal stability of the polymers was determined by thermogravimetric analysis (TGA). Performance evaluation of all the prepared polymers in SN150 mineral oil as viscosity index improver (VII), pour point depressant (PPD) and antiwear were carried out according to standard ASTM methods. The action mechanism of the additives as PPD was studied by photo micrographic image. Biodegradability of all the samples was tested through soil burial test (SBT).

Five terpolymers consisting of an alkyl acrylate (octyl acrylate/decyl acrylate/dodecyl acrylate), sunflower oil and styrene in different ratios (w/w) viz. 1:1:1, 2:1:1 and 3:1:1 were synthesized by free radical polymerization method using azobisisobutyronitrile (AIBN) initiator in toluene solvent. The polymers were characterized by FT-IR and NMR spectroscopy. Molecular weight of the prepared polymers was determined by gel permeation chromatography (GPC) method. Thermal stability of the polymers was determined by thermogravimetric analysis (TGA). Performance of the prepared polymers as viscosity modifier (VM), also known as viscosity index improver (VII), pour point depressant (PPD) and antiwear in different base oils were evaluated according to standard ASTM methods. Photo micrographic image were used to study the action mechanism of the additives as PPD. Biodegradability of all the polymers was tested through disc diffusion method. From the experimental results, it was observed that the ratio 2:1:1 is most effective for the preparation of terpolymers based on acrylate, sunflower oil and styrene. Moreover, it is also observed that efficiencies as VII and antiwear increase but PPD decrease with increasing the alkyl chain length of the prepared polymers.

Poly(1-vinylimidazole) (PVIm) hydrogels were synthesized through free radical polymerization/crosslinking of 1-vinylimidazole (VIm) in aqueous solutions with azobisisobutyronitrile (AIBN) used as the initiator and N,N′-methylenebisacrylamide (MBAAm) as the crosslinking agent. To quaternize PVIm, dimethylsulfate was used as the methylating agent. Pristine and quaternized PVIm hydrogels were characterized by spectroscopic techniques. Finally, ground hydrogels were used in anion adsorption. The amount of anion adsorbed (in m-eq. anion/g polymer) and adsorption% was determined for fluoride, bromide, nitrite, nitrate, phosphate and sulfate anions using ion chromatography techniques. The amount of phosphate adsorbed on QPVIm hydrogel was the highest and the amount of fluoride adsorbed on QPVIm hydrogel was the lowest. Ion chromatographic study showed that when 1/1 mol ratio of anion to polymer (on a repeating unit basis) was used, 24.7 % of fluoride, 60.6 % of nitrite, 61.6 % of bromide, 63.0 % of nitrate, 99.3 % of phosphate and 98.2 % of sulfate were removed from the medium.

Interpenetrating polymer networks (IPNs) based on polybutadiene (HTPB) and polymeric ionic liquid (PIL) networks were prepared using an in situ strategy. PIL network is obtained from a free radical co-polymerization of an ionic liquid monomer (ILM) and poly(ethylene glycol) dimethacrylate initiated with azobisisobutyronitrile. HTPB network is formed by isocyanate-alcohol addition between the hydroxyl end groups of telechelic HTPB and a pluri-isocyanate cross-linker, catalyzed by dibutyltindilaurate. The IPN containing 72 wt% PIL network exhibits one mechanical relaxation temperature as determined by Dynamic Mechanical Thermal Analysis (DMTA).

Reverse atom transfer radical polymerization (RATRP) of methyl methacrylate (MMA) under microwave irradiation (MI), using azobisisobutyronitrile (AIBN) /FeC13/triphenylphosphine (PPh3) as the initiating system, was successfully carried out in N, N-dimethylformamide (DMF) at 69°C. Plots of In ([MI0/[M]) vs. time and molecular weight evolution vs. conversion showed a linear dependence. A polymer for reaching 82% conversion, with molecular weight (Mn) 34,000 and polydispersity index (PDI) 1.37, was obtained under MI (90U') with the ratio of [MMA]0/[AIBN]0/[FeCl3]0/[PPh3]0 = 1600/2/4/8 in only 60 min; while 840 min was required under conventional heating (CH) process for reaching 82 % conversion (Mn = 48,000 and PDI = 1.31) at identical polymerization conditions, indicating a significant enhancement of the polymerization rates and apparent initiator efficiencies under MI.

Summary A new one-step synthesis of a set of macroinitiators for atom transfer radical polymerization (ATRP) via controlled radical polymerization is presented. The macroinitiators consist of methacrylate and p-chloromethylstyrene (CMS) and were synthesized by controlled radical polymerization in the presence of 1,ldiphenylethylene (DPE) using azobisisobutyronitrile (AIBN) as initiator. The resulting macroinitiators were used for the ATFW of different methacrylates yielding graft copolymers which were characterized by SEC and NMR.

It was found that p-aminostyrene (PAS) was easily oligomerized by CF3COOH (TFA) in CCl4 to give a low molecular weight oligomer 4 including phenylene, ethylidene and secondary amine groups in the backbone, i.e., the isomer of poly-p-aminostyrene 5. The NMR and IR spectra of the product are quite different from those of polymer 5 produced by 2,2'-azobisisobutyronitrile (AIBN) in toluene. The dimer D and trimer T were separated from the reaction solution through the preparative GPC. The reaction seems to proceed stepwisely to give D in the initial stage and finally the near pentameric oligomer 4 at the end of the reaction.

The telomerization of acrylic acid (AA) with thioglycolic acid (TGA) initiated with 2,2'-azobisisobutyronitrile (AIBN) was first investigated in organic medium (THF, 65°C). The kinetic study of this telomerization led to the determination of the TGA transfer constant (CT= 3,2). Then, the same study was performed both in aqueous medium and in water / THF mixtures. From these works it is emphasised that the nature of the solvent plays an important role on the transfer constant. Thus, the value of CT decreased from CT= 3,2 in THF to 0,5 in water. By this way, the "ideal" case of telomerization (CT= 1) was reached for a mixture of solvents: water / THF (80%, 20%, v/v).

Homogeneous polystyrene and silica gel polymer hybrids were prepared by in-situ radical polymerization method. Styrene monomer was introduced into a sol-gel reaction mixture of tetramethoxysilane (TMOS) and the polymerization was initiated by Azobisisobutyronitrile (AIBN), while sol-gel reaction of TMOS proceeded to form a silica gel. The homogeneity of the hybrids was found to be dependent on the amount of the acid catalyst. The homogeneity was confirmed quantitatively by measuring porosity of charred hybrids with nitrogen porosimetry method. It was found that polystyrene was dispersed at a nano-meter level in the silica gel matrix.

For a novel corrosion inhibitor for copper, the free radical copolymerization of vinyl imidazole(VI) and vinyl trimethoxy silane(VTS) was carried out in benzene at 68 °C using azobisisobutyronitrile(AIBN) as an initiator. The reactivity ratios of the two monomers were determined from instantaneous composition diagram: r VI =3.22 and r VTS =0. Thermal stability of poly(VI-co-VTS) depended on VTS mole fraction in the feed rather than the molecular weight of the copolymer, due to the disiloxane bond linkages formed during heating.

Linear macromolecules of the poly(2-ethylhexyl acrylate) were prepared by solution polymerization in toluene at 12 °C, using azobisisobutyronitrile as initiator. The polymer was fractionated and the fractions characterized by the methods of light scattering, osmometry and viscometry. Mark-Houwink-Sakurada relations at 25°C in solvents of different thermodynamical quality have been determined.

The solution copolymerization of acrylamide (AAm) with N-vinyl pyrrolidone (NVP) was investigated using azobisisobutyronitrile (AIBN) as an initiator at 60°C. The study was performed by measuring the rate of the copolymerization reaction, the molecular weights and by determining the monomer reactivity ratios. In addition, the thermal properties (thermal conductivity, thermal diffusivity and volumetric heat capacity) of the resulted copolymers in aqueous solutions were investigated at various temperatures. The kinetic results and the apparent reactivity ratios indicate that NVP is more reactive than AAm towards the copolymerization process. The values of the thermal properties whowed that the behaviour of such parameters depend on the polymer concentration, the temperatures and the content of vinyl pyrrolidone in the copolymeric chains.

The α, ω-diphenyl derivatives of 1,3,5-hexatriene and 1,3,5,7-octatetraene strongly retard the radical polymerization of methyl methacrylate (MMA); the effects are greater when initiation is achieved with benzoyl peroxide than when azobisisobutyronitrile is used. The tetraene and the triene are respectively 575 and not less than 240 times as effective as MMA in capturing the benzoyloxy radical at 60°C.

Acrylonitrile was polymerized by an insertion process on being added to solutions containing the adduct of the reaction of tetrakis(dimethylamino) titanium (T4) and azobisisobutyronitrile (AIBN). The obtained azo-linked polyacrylonitrile has appropriate initiating functionality for a subsequent vinyl polymerization.

Poly(vinyl oxazoline ester) and poly(stearyl methacrylate) were found to be good alien polymers for grafting of methyl methacrylate by suspension polymerization whereas poly(tridecyl methacrylate) was not a good backbone. Azobisisobutyronitrile was found to be an inefficient grafting initiator where azocumene that produces highly resonance and hyperconjugated stabilized dimethyl phenyl methyl radical was a superior initiator to benzoyl peroxide for grafting. Poly(stearyl methacrylate) was found to be a suitable polymeric stabilizer for nonaqueous suspension polymerizations.

It is shown that the alkyl chlorsilanes both induce and inhibit the N-vinyl pyrrolidone polymerization simultaneously. The conversion increases with the concentration rise of the alkyl chlorsilanes, but the molecular weights of the polymerization products are constant. These polymerization characteristics do not depend from the concentration ratio: [alkyl chlorsilane]/ [azobisisobutyronitrile].

Decomposition of azobisisobutyronitrile in benzene containing small amounts of methacrylonitrile produces a mixture of oligomers of methacrylonitrile. Analysis by gas chromatography-mass spectrometry indicates that combination is the preponderant (>90%) termination mechanism.

3,8,13,17-Tetramethyl-7,12-dicarboxy-2,18-bis(octadecyloxycarbonylethyl) porphinato zinc (DCPZn) was incorporated into bilayer membrane of liposomes of 1,2-bis(2,4-octadecadienoyl)sn-glycero-3-phosphocholine (DODPC). The liposomes were polymerized by initiators like water-insoluble azobisisobutyronitrile (AIBN) or/and water-soluble azobis(amidinopropane) dihydrochloride (AAPD). DCPZn does not disturb the molecular packing of DODPC in the bilayer and after the polymerization, DCPZn is fixed monomolecularly in the network of the crosslinked bilayer membrane, while in the monomeric bilayers the dispersion state of DCPZn depends on temperature and concentration.