Interaction Of Poly Research Articles

Investigation of the Interaction between Poly(trimethylene carbonate) and Various Hydroxyl Groups

The interaction of poly(trimethylene carbonate) (PTMC) with hydroxyl group compounds was investigated as a model for polymer blending with polysaccharides. While 1-butanol, 2-butanol, ethylene glycol, and 1,2-cyclohexanediol showed almost no detectable interaction with PTMC in both solution states with the 1H NMR and solid states with the FT-IR, glucose and cellobiose suggested a slight change in the spectral pattern in FT-IR analysis. The thermal properties of the blended samples of PTMC and these hydroxyl groups were also investigated. Although the blends of PTMC with 1-butanol and 2-butanol did not influence thermal degradation behaviors due to their low boiling points, the PTMC blend with a higher number of hydroxyl groups, especially glucose and cellobiose, tended to increase thermal resistance and glass transition temperature, hence showing the existence of an interaction through hydrogen bonding.

A sustainable Poly (deep eutectic solvents) based molecular imprinting strategy with experimental and theoretical elucidation: Application for removal of atrazine in agricultural wastewater

In this research, a fabrication of Poly(deep eutectic solvent) composed of choline chloride-methacrylic acid (ChCl-MAA) was developed to cross-link and polymerize through molecular imprinting technology (MIT). The results were analyzed using a simple syringe solid phase extraction (SPE) device combined with Poly(DES)-MIT strategy, with the aim of specifically removing atrazine (ATZ) from agricultural wastewater. Density functional theory was applied for the rapid prediction of optimal molar ratio (1:4) between the template (ATZ) and monomer (DES), yielding highly consistent results with experimental findings. The electrostatic potential (ESP) distributions and the independent gradient model (IGMH) were employed to investigate the types and strengths of weak interactions in Poly(DES). Due to the participation of DES in the polymerization reaction, Poly(DES) exhibited rapid adsorption equilibrium time (120 min) and excellent specificity recognition ability (selectivity factor of 14.02). The HPLC-DAD analysis system exhibited a good linear response in the range of 0.5∼500 mg L−1, with a detection limit (LOD) of 0.26 mg L−1 and a quantitation limit (LOQ) of 0.87 mg L−1. The admirable feasibility for the removal of ATZ (with a recovery rate of 99.93 %) from real agricultural wastewater substantiated the outlook of practical application of Poly(DES)-MIT strategy. In addition, the adsorption rate of Poly(DES) on ATZ only decreased by 5.80 % (from 96.60 % to 90.80 %) after five adsorption–desorption cycles, demonstrating its significant sustainability. This study combined computer-aided design with a novel green DES-mediated polymerization process to construct an environmentally friendly adsorbent with high selectivity for ATZ. From a quantum chemistry perspective, it was demonstrated that Poly(DES) selectively captures ATZ from agricultural wastewater mainly through hydrogen bonding interactions and van der Waals forces. The combined method of theoretical simulation and experimental verification showed vast potential in the field of safe cultivation of medicinal herbs and crops, opening up new possibilities for the precise monitoring of other pollutants in the environment.

Leveraging electronic interactions in poly (O-toluidine)/ cadmium sulfide nanocomposite for improved nitrogen dioxide sensing

Detecting nitrogen dioxide (NO2) at room temperature remains challenging for current gas sensor technologies. This study aims to address these limitations by developing chemiresistive sensors based on poly (O-toluidine) (POT)/Cadmium sulfide (CdS) nanocomposites. The combination of POT and CdS nanoparticles creates a specialized architecture to enable swift and sensitive NO2 detection at room temperature. Gas sensing evaluations demonstrated significant performance enhancements including 104/73 s response/recovery times and 73% sensitivity at 60 ppm NO2. The sensors also showed repeatability over cycles and stability over 60 days. Comparative analysis confirmed that integrating POT with CdS amplifies sensitivity and reduces response times compared to using POT alone. This establishes a materials-by-design strategy to surpass existing gas sensing limitations.

Molecular-Scale Exploration of Mechanical Properties and Interactions of Poly(lactic acid) with Cellulose and Chitin.

Poly(lactic acid) (PLA), one of the pillars of the current overarching displacement trend switching from fossil- to natural-based polymers, is often used in association with polysaccharides to increase its mechanical properties. However, the use of PLA/polysaccharide composites is greatly hampered by their poor miscibility, whose underlying nature is still vastly unexplored. This work aims to shed light on the interactions of PLA and two representative polysaccharide molecules (cellulose and chitin) and reveal structure-property relationships from a fundamental perspective using atomistic molecular dynamics. Our computational strategy was able to reproduce key experimental mechanical properties of pure and/or composite materials, reveal a decrease in immiscibility in PLA/chitin compared to PLA/cellulose associations, assert PLA-oriented polysaccharide reorientations, and explore how less effective PLA-polysaccharide hydrogen bonds are related to the poor PLA/polysaccharide miscibility. The connection between the detailed chemical interactions and the composite behavior found in this work is beneficial to the discovery of new biodegradable and natural polymer composite mixtures that can provide needed performance characteristics.

Regulating Lewis Acid–Base Interaction in Poly (ethylene oxide)‐Based Electrolyte to Enhance the Cycling Stability of Solid‐State Lithium Metal Batteries

Solid polymer electrolytes (SPE) offer an outstanding choice because of their lightweight, flexibility, and excellent thin‐film forming ability. However, the low ionic conductivity and poor lithium ion transfer number (tLi+) restrict its application in all‐solid‐state lithium batteries (ASSLBs). Herein, UIO66‐X metal‐organic frameworks with controllable Lewis basicity, acidity, or neutrality functional groups are synthesized successfully and then incorporated into the poly (ethylene oxide) (PEO) matrix to fabricate SPE. The influence of different organic ligands on the interface interaction between PEO and LiTFSI is investigated by solid‐state nuclear magnetic resonance, Fourier transform infrared spectoscopy and Raman tests, as well as density functional theory calculations. The Lewis acidity group plays a key role in enhancing the ionic conductivity and tLi+. As a result, the constructed Li–Li symmetrical cells retain stable cycling for 2300 h and the LiFePO4‐based ASSLBs deliver outstanding electrochemical properties with 147 mAh g−1 of reversible capacity after 500 cycles at 1C and 60 °C, 131 mAh g−1 after 150 cycles at 0.1C and 30 °C. The fabricated SPEs are self‐standing and flexible with good mechanical stability, demonstrating the great potential for practical application. The results can guide choosing the inorganic filler to prepare high‐performance SPE.

Interfacial Engineering of PVDF‐TrFE toward Higher Piezoelectric, Ferroelectric, and Dielectric Performance for Sensing and Energy Harvesting Applications

The electrical properties of pristine fluoropolymers are inferior due to their low polar crystalline phase content and rigid dipoles that tend to retain their fixed moment and orientation. Several strategies, such as electrospinning, electrohydrodynamic pulling, and template-assisted growing, have been proven to enhance the electrical properties of fluoropolymers; however, these techniques are mostly very hard to scale-up and expensive. Here, a facile interfacial engineering approach based on amine-functionalized graphene oxide (AGO) is proposed to manipulate the intermolecular interactions in poly(vinylidenefluoride-trifluoroethylene) (PVDF-TrFE) to induce β-phase formation, enlarge the lamellae dimensions, and align the micro-dipoles. The coexistence of primary amine and hydroxyl groups on AGO nanosheets offers strong hydrogen bonding with fluorine atoms, which facilitates domain alignment, resulting in an exceptional remnant polarization of 11.3µCcm-2 . PVDF-TrFE films with 0.1wt.% AGO demonstrate voltage coefficient, energy density, and energy-harvesting figure of merit values of 0.30VmN-1 , 4.75Jcm-3 , and 14pm3 J-1 , respectively, making it outstanding compared with state-of-the-art ceramic-free ferroelectric films. It is believed that this work can open-up new insights toward structural and morphological tailoring of fluoropolymers to enhance their electrical and electromechanical performance and pave the way for their industrial deployment in next-generation wearables and human-machine interfaces.

Mechanistic insights into poly(C)-binding protein hnRNP K resolving i-motif DNA secondary structures

I-motifs are four-strand noncanonical secondary structures formed by cytosine (C)-rich sequences in living cells. The structural dynamics of i-motifs play essential roles in many cellular processes, such as telomerase inhibition, DNA replication, and transcriptional regulation. In cells, the structural dynamics of the i-motif can be modulated by the interaction of poly(C)-binding proteins (PCBPs), and the interaction is closely related to human health, through modulating the transcription of oncogenes and telomere stability. Therefore, the mechanisms of how PCBPs interact with i-motif structures are fundamentally important. However, the underlying mechanisms remain elusive. I-motif structures in the promoter of the c-MYC oncogene can be unfolded by heterogeneous nuclear ribonucleoprotein K (hnRNP K), a PCBP, to activate its transcription. Here, we selected this system as an example to comprehensively study the unfolding mechanisms. We found that the promoter sequence containing 5 C-runs preferred folding into type-1245 to type-1234 i-motif structures based on their folding stability, which was further confirmed by single-molecule FRET. In addition, we first revealed that the c-MYC i-motif structure was discretely resolved by hnRNP K through two intermediate states, which were assigned to the opposite hairpin and neighboring hairpin, as further confirmed by site mutations. Furthermore, we found all three KH (hnRNP K homology) domains of hnRNP K could unfold the c-MYC i-motif structure, and KH2 and KH3 were more active than KH1. In conclusion, this study may deepen our understanding of the interactions between i-motifs and PCBPs and may be helpful for drug development.

Studies on the Interaction of Poly(phenylene methylene) with Silver(I) and Hexacarbonylchromium(0).

Complexes of poly(phenylene methylene) (PPM) with silver(I) ions and tricarbonylchromium(0) moieties, respectively, were synthesized. 13C NMR spectra indicate interaction of phenylene groups with silver(I) and chromium(0), and peak broadening implies dynamic behavior of the silver(I) complexes, with all phenylene groups temporarily involved in coordination, in contrast to the chromium complexes. About 5–10% of the phenylene groups are coordinated to metal atoms. 1H NMR and IR spectra, in the case of chromium(0), and the solubility of silver salts in the presence of PPM provide further evidence of coordination. The complexes are soluble in chloroform, but the silver complexes decay in tetrahydrofuran (second-order kinetics were observed in an example). The photoluminescence (fluorescence) of PPM is maintained upon complexation, although coordination of silver(I) seems to favor the so-called blue phase of PPM relative to the green phase by a factor of approximately two in PL spectra. The pronounced absorption of the tricarbonylchromium(0) units interferes with the blue phase, which almost disappears at a concentration of 50 mg/mL in PLE spectra, whereas the emission maximum of the green phase is hardly affected. This leads to a confinement of the emitted wavelength range of PPM. Thus, the perceived optical emission of PPM can be modified by coordinated entities.

Poly(methyl methacrylate) Nanocomposite Foams Reinforced with Carbon and Inorganic Nanoparticles—State-of-the-Art

Polymeric nanocomposite foams have attracted increasing research attention for technical reasons. Poly(methyl methacrylate) is a remarkable and viable thermoplastic polymer. This review highlights some indispensable aspects of poly(methyl methacrylate) nanocomposite foams with nanocarbon nanofillers (carbon nanotube, graphene, etc.) and inorganic nanoparticles (nanoclay, polyhedral oligomeric silsesquioxane, silica, etc.). The design and physical properties of poly(methyl methacrylate) nanocomposite foams have been deliberated. It has been observed that processing strategies, nanofiller dispersion, and interfacial interactions in poly(methyl methacrylate)–nanofiller have been found essential to produce high-performance nanocellular foams. The emergent application areas of the poly(methyl methacrylate) nanocomposite foams are electromagnetic interference shielding, sensors, and supercapacitors.

Intermolecular CH-π Electrons Interaction in Poly (9,9-dioctylfluorenyl-2,7-diyl) (PFO): An Experimental and Theoretical Study.

This study demonstrates the presence of CH-π interaction in poly [9,9-dioctylfluorenyl-2,7-diyl] (PFO-1) due to an aggregate formation of PFO-1 in the liquid state. The absorption spectra of PFO-1 in certain solvents at low concentrations showed a single band at 390 nm. However, when using high concentrations, a new band at 437 nm appeared. This band is due to the aggregate formation of PFO-1. The aggregate formation occurs as a result of the CH interaction of the n-alkyl side chains with π-electrons in the benzene ring. The optical characteristics of another conjugated polymer of poly [9,9-di-(2-ethylhexyl)-fluorenyl-2,7-diyl] (PFO-2) were investigated to confirm the CH-π interaction. The absorption showed only one wavelength at 390 nm without any new band at the end of the spectrum, even at higher concentrations and lower temperatures. The main reason for the absence of aggregate formation in PFO-2 is the sterical hindrance caused by the branched alkyl side chains. In addition, Density Functional Theory (DFT) was used to compute the HOMO–LUMO transitions, electron charge distribution, and frontier molecular orbitals for each polymer. The Mulliken charge distribution and demonstrated a notable difference in the reactivity of the alkyl side chain, confirming the higher ability of PFO-1 to form CH-π bonds. docking model emphasized that the band at 437 nm could be attributed to the interaction between CH in the n-alkyl side chain and π bonds in the aromatic rings of PFO-1.

Polymeric iodophors with poly(2-ethyl-2-oxazoline) and poly(N-vinylpyrrolidone): optical, hydrodynamic, thermodynamic, and antimicrobial properties

Formation of iodophors by interactions of poly(2-ethyl-2-oxazoline) and poly(N-vinylpyrrolidone) with molecular iodine dissolved in aqueous solutions with addition of potassium iodide and ethanol has been studied using a range of physicochemical techniques including UV–Vis spectroscopy, viscometry, dynamic light scattering, isothermal titration calorimetry and partitioning through semi-permeable membrane. It was established that poly(2-ethyl-2-oxazoline) exhibits greater ability to bind iodine compared to poly(N-vinylpyrrolidone). Despite the difference in the binding ability of these two polymers, their iodophors exhibited similar antimicrobial properties.

Tuning of interfacial interactions in poly(isoprene) ferroelastomer by surface modification of embedded metallic iron nanoparticles

Tuning of interfacial interactions in poly(isoprene) ferroelastomer by surface modification of embedded metallic iron nanoparticles

Visualization of Inter- and Intramolecular Interactions in Poly(3-hydroxybutyrate)/Poly(L-lactic acid) (PHB/PLLA) Blends During Isothermal Melt Crystallization Using Attenuated Total Reflection Fourier Transform infrared (ATR FT-IR) Spectroscopic Imaging.

Inter- and intramolecular interactions in multicomponent polymer systems influence their physical and chemical properties significantly and thus have implications on their synthesis and processing. In the present study, chemical images were obtained by plotting the peak position of a spectral band from the data sets generated using in situ attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopic imaging. This approach was successfully used to visualize changes in intra- and intermolecular interactions in poly(3-hydroxybutyrate)/poly(L-lactic acid) (PHB/PLLA) blends during the isothermal melt crystallization. The peak position of ν(C＝O) band, which reflects the nature of the intermolecular interaction, shows that the intermolecular interactions between PHB and PLLA in the miscible state (1733 cm−1) changes to the inter- and intramolecular interaction (CH3⋯O=C, 1720 cm−1) within PHB crystal during the isothermal melt crystallization. Compared with spectroscopic images obtained by plotting the distribution of absorbance of spectral bands, which reveals the spatial distribution of blend components, the approach of plotting the peak position of a spectral band reflects the spatial distribution of different intra- and intermolecular interactions. With the process of isothermal melt-crystallization, the disappearance of the intermolecular interaction between PHB and PLLA and the appearance of the inter- and intramolecular interactions within the PHB crystal were both visualized through the images based on the observation of the band position. This work shows the potential of using in-situ ATR FT-IR spectroscopic imaging to visualize different types of inter- or intramolecular interactions between polymer molecules or between polymer and other additives in various types of multicomponent polymer systems.

Interaction of Poly(methyl acrylate) with Carbon Nanotubes as a Function of CNT Diameter, Chirality, and Temperature

The use of carbon nanotubes (CNTs) is promising for ultrahigh-strength composite materials with tunable electrical and thermal properties. Noncovalent polymer wrapping onto CNTs has proven effectiv...

The Importance of Excellent π-π Interactions in Poly(thiophene)s To Reach a High Third-Order Nonlinear Optical Response.

Poly(thiophene)s have an inherently large third-order nonlinear optical (TONO) response, but applications are not straightforward due to unoptimized materials. Therefore, several structure-property relationships (molar mass, branching, regioregularity) are investigated to unravel which structural modifications give the highest TONO response. Poly(3-hexylthiophene) with different molar masses, poly[3-(2-ethylhexyl)thiophene] with different molar masses, and random copolymers with different degrees of regioregularity are synthesized and measured by UV-vis spectroscopy and the third harmonic scattering technique. Every structural modification that leads to an increase in π-π interactions in poly(thiophene)s leads to an increase in the TONO response of the material. Therefore, a material with a high molar mass, an unbranched alkyl side chain, and a high regioregularity degree is preferably tested as a promising TONO material.

Adsorption of Polyadenylic acid on graphene oxide: experiments and computer modeling

In this work, we study the adsorption of poly(rA) on graphene oxide (GO) using AFM and UV absorption spectroscopies. A transformation of the homopolynucleotide structure on the GO surface is observed. It is found that an energetically favorable conformation of poly(rA) on GO is achieved after a considerable amount of time (days). It is revealed that GO can induce formation of self-structures of single-stranded poly(rA) including a duplex at pH 7. The phenomenon is analyzed by polymer melting measurements and observed by AFM. Details of the noncovalent interaction of poly(rA) with graphene are also investigated using molecular dynamics simulations. The adsorption of (rA)10 oligonucleotide on graphene is compared with the graphene adsorption of (rC)10. DFT calculations are used to determine equilibrium structures and the corresponding interaction energies of the adenine-GO complexes with different numbers of the oxygen-containing groups. The IR intensities and vibrational frequencies of free and adsorbed adenines on the GO surface are calculated. The obtained spectral transformations are caused by the interaction of adenine with GO.

A theoretical study of the structural and electronic properties of poly(9-vinylcarbazole) interacting with small-diameter single-walled carbon nanotubes

Density functional perturbation theory (DFPT) and time-dependent density functional perturbation theory (TDDFPT) calculations were employed to study the molecular and electronic structures, linear and nonlinear optical properties, optical phonon modes and vibrational properties of the interaction of poly(9-vinylcarbazole) (PVK)–small-diameter single-walled carbon nanotube (SWCNT) composites. Our calculations show that the chemical connection between PVK and SWCNTs is only through the relatively weak [Formula: see text]–[Formula: see text] and [Formula: see text]–H bonds. PVK and SWCNTs have different electron accepting abilities and we believe this is the major factor responsible for the charge transfer processes we observe in the calculations. We notice an increase in polarizability value from 152 a.u. (PVK) to 517 a.u. (PVK–SWCNTs), making the PVK–SWCNT composite an ideal model for applications such as mechanical and optoelectronics. Also, the result of our calculations under the time-dependent density functional perturbation theory hinges on the idea that the large value of the polarizability calculated for our composite model is an attribute which can be inferred to processes of charge transfer. Our finding corroborates the fact that non-covalent functionalization is one of the effective chemical methods by which the nonlinear optical response properties of PVK–SWCNT composite may be enhanced.

Effect of pore solution calcium and substrate calcium on PMMA/cement paste interface during early stages of hydration

AbstractThe interfacial shear strength of polymer thin film coating on calcium–silicate–hydrate (C–S–H) or cement paste significantly depends on the time‐point, from addition of water, when the polymer is coated. This is because the physico‐chemical properties of C–S–H surface evolve over time as hydration progresses. The instant of coating thus determines the interfacial performance of a thin film coating in an organic‐inorganic material system. In this work, we provide molecular insights into the interactions of poly(methyl methacrylate) (PMMA) functional groups with the pore solution calcium and bound substrate calcium present in hydrating C–S–H. The experimental observation reveals that PMMA thin film coated on second day of hydration exhibits larger interfacial shear strength than when coated on the 28th day. The possible reasons for this observations are: a) chemical crosslinking of two oxygen atoms from two different PMMA polymer chains by pore solution calcium ions and b) the physical interaction between double bond oxygen (O1) present in –COO functional group of PMMA with pore solution calcium. In this work, physical interaction between double bond oxygen (O1) present in –COO functional group of PMMA with pore solution calcium and substrate calcium in C–S–H is addressed.

Interaction of Poly(benzoyl thiocarbamate)-Modified Hyperbranched Polyester with Co(II) and Cu(II) Nitrates

The interaction of Co(NO3)2 and Cu(NO3)2 with hyperbranched polyester containing 7 terminal benzoyl thiocarbamate groups has been studied by IR-Fourier and electron absorption spectroscopy. А new polynuclear complexes of Co(II) and Cu(II) with poly(benzoyl thiocarbamate)-modified hyperbranched polyester have been synthesized. It has been found that the oxygen and sulfur atoms of the peripheral benzoyl thiocarbamate fragments of the macroligand are involved in coordination with metal ions, the metal to ligand ratio being 7 : 1.

Abstract P-16: Interaction of Poly(ADP-Ribose)Polymerase1 and Poly(ADP-Ribose)Polymerase2 with Nucleosome during Base Excision Repair

Abstract P-16: Interaction of Poly(ADP-Ribose)Polymerase1 and Poly(ADP-Ribose)Polymerase2 with Nucleosome during Base Excision Repair