Oleg Dzhuzha

New hydroxyl-functionalized aromatic sulfonamide, N-butyl-4-(3-hydroxypropylamino)benzenesulfonamide (BHPA-BSA), has been synthesized and tested as potential plasticizer for polyamide 12 (PA-12). According to results of quantum-chemical calculations, BHPA-BSA has a higher binding energy with the monomer unit of PA-12 compared to commercial plasticizers N-butylbenzenesulfonamide (BBSA) and N-(3-hydroxypropyl)benzenesulfonamide (HP-BSA). Specific combination of the sulfonamide and hydroxyalkyl groups in BHPA-BSA allows the formation of two hydrogen bonds with the amide group of PA-12 through one of the sulfonamide’s oxygen atom as a hydrogen bond acceptor and hydroxyl group as a hydrogen bond donor. PA-12 films containing 15 and 20 wt% BHPA-BSA or commercial plasticizers have been prepared by compression moulding. IR analysis revealed that both sulfonamide and hydroxyl groups of BHPA-BSA participate in the hydrogen bonding with the amide group of PA-12. Differential scanning calorimetry show that the new sulfonamide lowers the glass transition temperature of PA-12 by more than 40 °C, indicating a plasticizing effect comparable to common plasticizers. The results of dynamic mechanical analysis also revealed the high plasticizing efficacy of BHPA-BSA toward PA-12, which is manifested in the twofold reduction in the storage modulus of the polymer.The volatility of the BHPA-BSA from the PA-12 matrix at 120 °C is five times lower than that of commercial plasticizers. Moreover, the new sulfonamide exhibits excellent resistance to release in hexane, in contrast to BBSA and HP-BSA. Thus, the functionalization of BBSA with the hydroxyalkyl group is an efficient approach to synthesize new low-volatility plasticizers for polyamide resins.

Синтезовано довголанцюговий біологічно активний естер 4-гідроксибензойної кислоти – додецил-4-гідроксибензоат (ДГБ). Отримано композиційні полімерні плівки на основі поліаміду 12 (ПА-12), які містять 25 масових відсотків ДГБ. Методом диференційної сканувальної калориметрії встановлено, що ДГБ знижує температуру склування ПА-12 від 46 до -25 °С і температуру плавлення від 178 до 168 °С. Це свідчить про високу ефективність сполуки як пластифікатора для ПА-12. Згідно з результатами термогравіметричного аналізу, полімерна композиція ПА-12/ДГБ має температуру початку деструкції 324 °С і є термічно стійкою в області температур промислової переробки ПА-12 (220-300 °С). ДГБ є перспективною поліфункціональною модифікуючою домішкою до поліамідів технічного і медичного призначення, яка може суттєво підвищувати гнучність полімерних виробів і надавати їм антимікробних властивостей.

Long-chain imidazolium-based ionic liquids (ILs) possess a broad-spectrum biological activity and are considered promising antifouling agents for protective coatings. A new hydrophobic IL, 1-dodecyl-3-methylimidazolium dodecylbenzenesulfonate (C₁₂C₁IM-DBS), has been synthesized, and a modified epoxy coating material containing 10, 20, and 30 wt% of this IL was prepared by dissolution of C₁₂C₁IM-DBS in commercial DER 331 epoxy resin, followed by a curing phase with diethylenetriamine. Infrared analysis revealed physicochemical interactions between the hydroxyl groups of the resin and the IL. Spectrophotometric studies showed no release of C₁₂C₁IM-DBS after 30 days of exposure of the modified coatings to water. The plasticizing effect of the IL on the epoxy resin was established by differential scanning calorimetry analysis. The introduction of 10 and 20% C₁₂C₁IM-DBS into DER 331 reduced its glass transition temperature from 122.8 °C to 109.3 and 91.5 °C, respectively. The hardness of epoxy resin decreased by approximately 26% after the introduction of the IL. Moreover, DER 331/C₁₂C₁IM-DBS coatings on steel substrates showed significantly improved impact resistance compared to neat resin. The antibiofilm efficiency of DER 331/C₁₂C₁IM-DBS coatings was evaluated by assessing the capability of two biofilm-forming model strains, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa PA01, to form attached biofilms on the surface. The IL effectively inhibited S. aureus surface-associated biofilm development even at the lowest content of 10%. On the contrary, an approximately 50% inhibition of biofilm metabolic activity was detected for DER 331/C₁₂C₁IM-DBS coatings containing 20% and 30% of the IL. Overall, the results of this study indicate that the hydrophobic IL C₁₂C₁IM-DBS is an efficient modifying additive for epoxy resins, which can significantly improve their operational properties for various industrial applications.

The results of the study are presented, which testify to the perspective of using the tertiary amide of oleic acid N,N-dibutylleamide as a modifying admixture for polyvinyl chloride.

New proton exchange membrane based on polyimide Matrimid® (PI) and hydrophobic protic ionic liquid, 1-methylimidazolium bis(trifluoromethylsulfonyl)imide (MIM-TFSI), has been prepared by casting from methylene chloride/dimethylformamide solution. Infrared analysis revealed physicochemical interactions between 1-methylimidazolium cations and imide groups of PI. The results of mechanical testing indicate significantly reduced tensile strength of PI/MIM-TFSI composite membrane compared to neat polymer. Moreover, the dynamical mechanical analysis results revealed sharp drop in storage modulus (E´) of the polymer film above 60 °C. To improve the elastic properties of the membrane, PI was successively cross-linked with polyetheramine Jeffamine® D-2000 (10 mol. %) in methylene chloride/dimethylformamide solution, as well as in solid film at 100 °C. This approach allowed to prepare PI/Jeffamine/MIM-TFSI (70 wt. %) composite film which has an acceptable E' value of 210 MPa at 140 °C. According to thermal gravimetric analysis data, PI/Jeffamine/MIM-TFSI composite has a thermal degradation point (i.e. 5 % weight loss) of 286 °C. The ionic conductivity of PI/Jeffamine/MIM-TFSI composite membrane is around 10–4 S/cm at room temperature and reaches the minimal level of 10–3 S/cm, required for fuel cell applications, above 100 °C. Overall, the results of this study indicate that the cross-linking of polyimide Matrimid with flexible polyetheramine Jeffamine is an efficient approach for preparing dense composite membrane with high content of the protic ionic liquid. Such polymer-electrolyte membrane has the reasonable combination of good stiffness, thermal stability, and ionic conductivity and therefore is a promising candidate for use in fuel cells operating at elevated temperatures in water-free conditions.

The article deals with the antifouling resistance in the fresh water of the protective coatings based on the ship paint XC-413 containing 5% of hydrophobic cationic biocide 1,3-didodecylimidazolium tetra fluoroborate (DD1M-BF₄). The biocidal additive was found to have high leaching resistance off the coating and improve its hydrophobicity. After 228 days exposure in the Dnipro River the fouling biomass was formed mainly by the Dreissena polymorpha (92.5%). The surface of DD1M-BF₄-modified coatings showed more than twenty time reducing of total biomass comparatively to control substrates. The obtained results showed the considered cationic biocides to be promising antifouling additives for industrial stains, used for protection of the underwater construction and vessels.

The choice of efficient antimicrobial additives for polyamide resins is very difficult because of their high processing temperatures of up to 300 °C. In this study, a new, thermally stable polymeric biocide, polyhexamethylene guanidine 2-naphtalenesulfonate (PHMG-NS), was synthesised. According to thermogravimetric analysis, PHMG-NS has a thermal degradation point of 357 °C, confirming its potential use in joint melt processing with polyamide resins. Polyamide 11 (PA-11) films containing 5, 7 and 10 wt% of PHMG-NS were prepared by compression molding and subsequently characterised by FTIR spectroscopy. The surface properties were evaluated both by contact angle, and contactless induction. The incorporation of 10 wt% of PHMG-NS into PA-11 films was found to increase the positive surface charge density by almost two orders of magnitude. PA-11/PHMG-NS composites were found to have a thermal decomposition point at about 400 °C. Mechanical testing showed no change of the tensile strength of polyamide films containing PHMG-NS up to 7 wt%. Antibiofilm activity against the opportunistic bacteria Staphylococcus aureus and Escherichia coli was demonstrated for films containing 7 or 10 wt% of PHMG-NS, through a local biocide effect possibly based on an influence on the bacterial eDNA. The biocide hardly leached from the PA-11 matrix into water, at a rate of less than 1% from its total content for 21 days.